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Is raw food healthy? + Recipes

Raw food would be very healthy - see recipes, but many raw foodists eat unhealthy because of missing or incorrect information.

Portrait of a nutritionist showing fresh vegetables for raw use.

Introduction

Raw food fascinates and polarizes at the same time. While some see it as "living food" rich in vitamins, phytochemicals and enzymes, others perceive it as a radical or difficult-to-implement form of nutrition.

At the same time, historical and modern research shows that raw food offers both health benefits and risks. These range from cardiovascularly favorable lipid profiles to potential nutrient deficiencies if the diet is unbalanced. The question, therefore, is less about whether raw food is healthy, but rather how to make it sensible, balanced, and practical for everyday life.

This article introduces the basics, variations, health aspects and scientific findings of raw food nutrition – and shows why it has therapeutic potential for some people, while it presents a challenge for others.

What is raw food?

Raw food nutrition is a dietary pattern that consists largely or exclusively of uncooked foods. Depending on the specific definition, raw animal products may also be considered raw food. The term "raw vegan" encompasses an exclusively plant-based raw food diet, with or without grains. Semler distinguishes between a diet for healthy individuals and a temporary therapeutic diet for the sick.

Many raw food enthusiasts also accept gentle heating or drying below 42 °C. In this case, cold-extracted honey, cold-pressed vegetable oils, gently dried fruits and cold-smoked products, as well as fermented and lactic acid-cured vegetables, are considered raw food. Instead of cooking, alternative preparation methods are used – such as juicing, puréeing, soaking, sprouting, or drying.¹

In certain circles of the raw food movement, raw food is considered "living food", while cooked food is seen as "dead" or "denatured" because some enzymes and delicate nutrients are lost through heat. This idea is based on naturism, a reverence for nature and life, and tends toward a kind of religious veneration of nature.

Why do humans "cook"?

In fact, humans are the only living beings that use heat in a controlled, conscious way to "cook" food. Claims about animal "cooking" have not been substantiated upon closer examination. The deliberate ignition and control of fire for food preparation is, according to current scientific understanding, truly only documented in humans. "Cooking" is a cognitively and culturally unique ability. It serves to inactivate foodborne pathogens, destroy toxins, extend shelf life, and improve the digestibility and bioavailability of nutrients. Cooking alters the taste, texture, and aroma of food. Consequences such as the loss of certain nutrients, the denaturation of proteins, and the formation of toxic compounds (acrylamide, fatty acid esters, etc.) also occur.

Evolutionary biology has demonstrated that humans are biologically adapted to cooked food. In particular, the reduction in size of the mouth, teeth, stomach, and large intestine proves this adaptation to easily chewed and quickly digestible food. The present study shows that dietary habits (especially cooking) have altered some genes. The improved digestibility of cooked tubers led to increased activity in genes involved in carbohydrate metabolism. Immune system genes show less activity, especially after the consumption of cooked meat: cooking reduces the burden on the immune system because it neutralizes harmful substances or pathogens. Nevertheless, humans benefit from the non-thermal processing of some raw food products.¹⁹

Why many people reject raw food or have difficulty consuming more raw food can be read here: Raw food? No, thank you!

What do "raw foodists" eat?

A raw food diet encompasses a wide variety of fresh fruits, vegetables, wild herbs, nuts, seeds, and sprouts. A popular form of raw food is raw veganism. Especially in English-speaking countries, you'll find countless recipes under the term "raw vegan". You can find our delicious vegan raw food recipes here: raw vegan recipes.

The term "raw food diet" is not uniform, as in practice there is no single "raw food diet". It is often a combination of various recommendations. Here you will find more information about the different forms of raw food diets.

Some raw foodists eat raw animal products:

Tartare (beef steak tartare, steak tartare): raw, minced beef, often with raw egg yolk
Carpaccio: wafer-thin slices of raw beef
raw fish such as sashimi, pickled rollmops or anchovies
raw eggs
Raw milk and yogurt made from it
partly insects and larvae

100 % raw food or less?

According to the literature, a strict raw food diet can offer benefits for a certain period during illness. Recommendations often include a preceding therapeutic fast. This has been particularly successful in treating persistent skin diseases and severe rheumatism. A strict raw food diet following therapeutic fasting can deepen and stabilize its therapeutic effects. For long-term nutrition, there are varying recommendations regarding the amount of raw food (70–100 percent by weight) and whether animal products should be avoided or remain part of the diet.¹

A healthy raw food diet is a plant-based whole food diet. The proportion of raw food can be adjusted individually and seasonally. In some cases of illness, a whole-food vegetarian diet with 50 % raw food content leads to significant therapeutic success.¹⁵

Ernst Erb describes his experiences on this question in the article: Exclusively raw food?

Why raw food?

Several reasons support a raw food diet. For many people, the health benefits are the deciding factor. Increasingly, animal welfare and sustainability are becoming the focus of the raw food community.

Health benefits of raw food

Many people choose this diet for health reasons. Raw food provides more vitamins, minerals, fiber, and enzymes than cooked food. A raw food diet also helps to avoid highly processed foods (junk food).

Scientific evidence regarding the health benefits of raw food is limited, presumably due to a lack of research interest. Furthermore, scientists avoid any association with raw food propaganda.

Edmund Semler He describes this as follows: many physicians find the idea of being able to favorably influence the course of serious illnesses solely with "greens" too simplistic and, due to the slow onset of effects, too unattractive or spectacular. His 2006 dissertation Raw Food: Historical, Therapeutic and Theoretical Aspects of an Alternative Diet documented the state of scientific knowledge regarding the significance of raw food as a long-term diet and as therapy.

There is little to no funding available for this topic, because vegetables, fruit, nuts, and the like don't generate much income.¹

One of the first large-scale studies (201 participants) was conducted by Carola Strassner in 1998. The aim of the "Giessen Raw Food Study" was to document the various branches of the raw food movement in Germany and to investigate the eating habits and nutritional status of raw foodists. The blood samples used for this study were part of the initial survey in spring 1994. Based on these archived samples, the two subsequent studies, among others, conducted further analyses. In 2003, a modified questionnaire from the Giessner Raw Food Study was used, to which 116 people responded. Of these, 73 people were still following a raw food diet at the time of the survey. Eight people had been eating raw food for more than 10 years, and 43 people for more than 5 years.

Koebnick et al. (2005) analyzed the lipid and homocysteine profiles of raw foodists. They consumed approximately 1500 to 1800 g of raw plant-based foods daily. Only 14 % of the participants had elevated LDL cholesterol levels, and none showed elevated triglyceride levels—both findings favorable for cardiovascular health. At the same time, 46 % had low HDL levels, and 38 % suffered from a vitamin B₁₂ deficiency, which was associated with elevated homocysteine concentrations.²

The study highlights the cardioprotective potential of a raw food diet and the necessity of targeted vitamin B₁₂ supplementation when following a strict raw plant-based diet. This is because a vitamin B₁₂ deficiency leads to higher homocysteine concentrations, which damages the vascular endothelium and increases the risk of thrombosis and stroke.

Garcia et al. (2008) examined the vitamin A and carotenoid status of the same participants in the Giessen raw food study. The participants consumed approximately 95 % of their diet as raw food, primarily fruit. Vitamin A status was within the normal range in 82 % of the participants. Beta-carotene levels suggesting a protective effect against chronic diseases were 63 % of the participants. Only lycopene levels were below the reference values, with 77 % of participants having levels below the reference values. Lycopene is a carotenoid. Its concentration in plasma is influenced by fat intake. Heating reduces the total carotenoid content but increases the bioavailability of certain carotenoids (including lycopene).

In addition to carotenoids, vegan raw foodists consume other secondary plant compounds that have numerous positive effects on our health.

In a cross-sectional study (2007), a group of raw foodists (21 participants) showed lower blood pressure values than groups following a Western diet. Regular endurance exercise reduces cardiometabolic risk.¹⁷

Regarding joint problems, there are positive findings for a raw food diet. In addition to reduced shoulder pain in patients with fibromyalgia, the present review (2023) showed relief from subjective symptoms of rheumatoid arthritis.¹⁰

Particularly revealing regarding food safety is a study by Monien et al. (2024) that compared acrylamide levels in omnivores, vegans, and strict raw foodists. Acrylamide is formed when carbohydrate-containing foods are heated above 120 °C—for example, during frying, baking, or roasting—and is considered a potential carcinogen. Raw foodists reached only about 25 % of the urinary acrylamide levels and about 48 % of the hemoglobin adduct levels of omnivores, thus exhibiting a significantly lower external exposure. At the same time, the data provided evidence of relevant endogenous acrylamide production in the body, independent of dietary intake. According to the authors, this endogenous production is considerably higher than previously assumed based on urinary markers. For raw foodists, this means that despite greatly reduced external acrylamide exposure, a certain amount of internal production remains, the health relevance of which has not yet been conclusively assessed.⁴

Raw vegan elite athletes – fit thanks to raw food?

That a raw food diet is possible for high-performance athletes is demonstrated by a much-cited case report by Leischik & Spelsberg (2014). They examined a 48-year-old endurance athlete who had completed a triple Ironman distance: 11,4 km swimming, 540 km cycling, and 126 km running in 41 hours and 18 minutes. At the time of the examination, the athlete had been eating a raw vegan diet for six years; prior to that, he had been vegan for three years and vegetarian for thirteen years.⁵

The athlete showed no signs of malnutrition or health problems. Compared to a control group of ten age-matched Ironman triathletes on a mixed diet, he even exhibited a higher oxygen uptake at the respiratory compensation point – a measure of aerobic performance capacity. Leischik & Spelsberg conclude: This case report suggests that a raw vegan diet is not harmful to elite athletes. Over long distances, it is compatible with exceptional physical performance in the aerobic zone.⁵

Raw food as therapy

In the 19th century, numerous non-professionals and physicians in German-speaking countries experienced that a temporary raw food diet could alleviate or even cure illnesses. This growing awareness of the therapeutic power of nature, simplicity, and self-healing, within the context of the emerging life reform movement, contributed to the development of the first major traditional raw food movement of the 1920s and 1930s.^1,15

In Germany, Adolf Just founded the first natural healing sanatorium in 1896. Together with his brother Rudolf Just, he treated thousands of patients in Jungborn with therapeutic fasting followed by a raw food diet. A structured observation of the effects of the raw food diet on various diseases was carried out from 1900 onwards by the Swiss physician Max Bircher-Benner. He treated more than 10,000 people at his clinic in Zurich, Lebendige Kraft (Living Force), and published numerous case reports. In Austria, the physician Reinhold Schwartz was considered a pioneer. In 1922, he opened the Dr. Schwartz Natural Healing Sanatorium in Altheim (Upper Austria) and used raw food and fasting as therapies.

From the mid-1920s to the mid-1940s, medical and scientific research succeeded in more intensively investigating the physiological and therapeutic effects of raw food. The physicians of the traditional raw food movement used strict raw food diets exclusively as a targeted healing method. They determined the proportion of unprocessed food according to the physical and mental condition of the individual patient. For long-term nutrition, these physicians generally recommended a whole-food diet with approximately 50 % raw food – a ratio that favors whole-food nutrition.¹

World War II brought the first raw food movement to an end. Raw food therapy almost fell into oblivion. It wasn't until the 1980s and 1990s that raw food books reappeared. These often advocated a purely raw food diet and used it not as a therapy, but as a long-term way of eating. Characteristic of this modern raw food movement is the strong presence of non-physicians and non-scientifics among the authors, while experts are rare.

Since the 2000s, the "raw food revolution" has been considered a modern trend. It focuses on an ethically sound and ecological lifestyle, which is why veganism is so prevalent. Individualism is central – everyone finds their own ideal approach based on their constitution. Science plays a less prominent role. Nevertheless, medical and scientific studies on (vegan) raw food diets have been conducted since then; see the section on: Health Benefits of Raw Food.

Raw food therapies are occasionally being used again. Recent studies have been conducted by the Hippocrates Health Institute (HHI) in Florida. This institute combines a strictly vegan raw food program with other complementary medicine elements. The studies showed that raw food as a therapeutic tool has significant effects not only on the body, but especially on the mind and emotions. The willingness to commit to a long-term approach depends less on the strictness of the diet than on personal (financial) resources and the extent of one's own suffering.

In the pilot study by Link et al. (2008), researchers investigated changes in quality of life, anxiety levels, stress levels, and various immune markers in guests of the HHI. Over the course of 12 weeks, overall quality of life increased by 11,5 %; the largest contribution to this improvement came from the psychological component (+14,5 %).⁶

Anxiety decreased by 18,6 %, and perceived stress levels by 16,4 %. Objective immune markers—CRP, lymphocytes, T cells, and B cells—remained stable. However, cytotoxic immune cells CD4, CD8, and NK cells declined slightly—a finding that suggests a reduction in chronic inflammatory activity.⁶

The second study by the same research team focused on the question of feasibility: Who actually maintains a raw food diet after such a stay? A higher level of education, greater suffering due to illness, and a high sense of self-efficacy showed the strongest influence on long-term adherence. The personal conviction of being able to implement the dietary change permanently is also important. Future intervention programs that aim to use raw food diets therapeutically should therefore specifically target strengthening this sense of self-efficacy.⁷

Are there health risks associated with a raw food diet?

Many people who follow a raw food diet do so for health reasons. The switch to a raw food diet is often due to illness (raw food diet as therapy). One study shows that among raw foodists, those with underlying health conditions tend to follow this diet for longer.⁷

Accordingly, many raw foodists have health problems before switching to this diet. Therefore, poorer health does not automatically imply a raw food diet. Many deficiencies already exist before the transition to this way of eating. Nevertheless, there are a few health risks that well-informed raw foodists should be aware of.

To help you better understand the changes, you should have important health parameters checked by your doctor before and after switching to (more) raw food.

A complete switch to a raw food diet is risky if the knowledge of how to implement it correctly is lacking. Too often, raw foodists eat a one-sided and consequently unhealthy diet – usually without sufficient knowledge of the necessary composition.

Therefore, it's important not to adopt a raw food diet based on the recommendations of a "raw food guru" or "raw food pope". Ideological distortion leads to nutrient deficiencies and thus health problems. Anyone who wants to follow a raw food diet long-term should possess the necessary nutritional knowledge.

It is therefore not surprising that the authors Pahlavani and Azizi-Soleimán, in a review (2023) on raw food diets, do not recommend a purely vegan raw food diet with more than 90 % raw food over a longer period. They argue that this often leads to underweight, micronutrient deficiencies, and related complications.¹⁰

The effects of a long-term raw food diet, when followed correctly, have not been scientifically investigated or have been skewed in cohort studies by raw foodists who followed the diet incorrectly. Read a critical book review of a book by a former raw food guru on this topic. Here is a critical review of the "Giessen Raw Food Study".

Germ contamination

Raw animal products (meat, fish, raw milk) pose a risk of bacterial contamination and therefore food poisoning. Those who follow a vegan raw food diet avoid these sources of danger. Sprouts can contain bacteria. Thorough hygiene is especially important when handling raw products.

Underweight and nutrient deficiencies

An ill-considered raw food diet is more likely to lead to underweight. Koebnick et al. (1999) demonstrate that long-term raw foodists often have a lower weight. Of 513 participants, 15 % of the men and 25 % of the women were underweight. Approximately 30 % of women under 45 years of age suffered from partial to complete amenorrhea (absence of menstruation). Female participants with a high raw food intake (>90 %) were more frequently affected than those with a moderate raw food intake.⁸

It is therefore essential to consume enough calories. Nuts and seeds provide energy and valuable nutrients. Mung bean sprouts and sprouted lentils are a good option for raw consumption. Certain grains and pseudocereals can be sprouted. See the article on phytic acid/phytate and soaking and sprouting.

The quantity and composition of any diet are crucial. A one-sided diet leads to nutrient deficiencies. Vegans and raw vegans must supplement vitamin B₁₂. Typical deficiencies include calcium, iodine, zinc, and vitamin D.

This is not just for vegans or vegetarians:
Vegans often eat unhealthily. Avoidable nutritional mistakes .

Bone health

A study showed that raw vegans had lower bone density compared to Western omnivores. However, the analysis was based on only 18 people, which limits its significance.¹¹

Adequate calcium and vitamin D intake is important for healthy bones.

Mineral water with a high calcium content helps meet daily requirements. Milk and dairy products (including raw milk) offer no benefit for bone health and are therefore not recommended. Why does consuming dairy products have the opposite effect on bone health?
Vitamin D is one of the critical vitamins for everyone. According to the National Nutrition Survey II (NVS II), 90 % of the population in Germany does not meet the recommended intake. Regular, moderate sun exposure (without sunscreen) promotes vitamin D production – but avoid excessive UV exposure and sunburn! In winter, there is often a need for vitamin D supplementation.

Dental health

Studies exist on the dental health of raw foodists. A raw food diet alters several factors affecting teeth and tooth enamel.

A high fruit intake leads to increased fruit acid production. This lowers the pH level and attacks tooth enamel. A 1999 study with 130 participants showed that people with a raw food diet were more likely to experience dental erosion.¹³

However, raw food requires intensive chewing, which reduces the risk of tooth decay. A 2020 study of 59 raw vegans and 59 omnivores showed that the raw vegan group had better dental health.¹⁴

For better dental health when following a raw food diet, you should consider the following:

Combine fruits with neutralizing vegetables or nuts.
Rinse your mouth with water after eating fruit.
Important: Do not brush your teeth immediately, as tooth enamel is softer shortly after contact with acid.

Animal welfare and sustainability

Besides health aspects, many people are motivated by ecological and ethical convictions to adopt a raw food-based diet. Abstaining from or limiting animal products reduces animal suffering and contributes to sustainable agriculture. Most plant-based foods have a smaller ecological footprint, meaning they burden the ecosystem less than animal products. Furthermore, plant-based foods often require no packaging, produce less waste, and are compostable.

Animal welfare and environmental protection are central elements of the "new raw food scene" that has emerged since the 2000s. This scene differs significantly from the raw food movement of the 1980s and 1990s. Earlier raw food diets were characterized by "simplicity" and "naturalness. ^"The "raw revolution" focuses on creative preparation techniques and visually appealing and flavorful raw vegan dishes.

Further reasons for switching to a raw food diet can be found in Ernst Erb's autobiographical article: Why raw food?

What constitutes a healthy raw food diet?

A healthy raw food diet is also possible with 90 or 100 % raw food. Opt for a varied diet that provides all essential nutrients and sufficient calories. Be critical of restrictive diets and dogmatic health claims.

Are you specifically looking for foods with a high content of specific nutrients?
Our nutrient comparison table will help you with that.

The majority of raw food should consist of vegetables, not fruit (ratio of 4:1). Certain plant-based foods yield more phytochemicals when steamed. Read more about this here: Bioavailability and synergistic effects of phytochemicals. In the long term, fruitarianism (fruganism) is clearly harmful. It has nothing to do with the diet of the Jain people (Ahimsa).

In addition, consume fresh herbs, seeds, nuts, and sprouted grains (if you tolerate them), as well as pseudocereals. Certain mushrooms can be eaten raw, such as velvet shank, shiitake, button mushrooms, and king oyster mushrooms (but not oyster mushrooms!). Larger quantities of mushrooms can cause problems like nausea, bloating, or diarrhea. Start with one or two raw mushrooms, perhaps finely chopped in a salad. You can then gradually increase the amount.

You should avoid sugar substitutes such as honey, agave syrup, maple syrup (usually not raw), or other sugar substitutes because they contain a lot of free (unbound) sugar. Opt instead for ripe bananas, chopped dates, raisins, or other suitable dried fruits, because the sugar in these is bound within the cells. You can find further explanations under "Healthy Sweetness? Between Myth and Reality".

Several prominent doctors in the US, especially cardiologists, actively advocate an oil-free diet (more information on this can be found under rapeseed oil). Instead of vegetable oil, you should consume nuts and seeds.

Opt for flaxseeds, hemp seeds, chia seeds, sweet lupin seeds, walnuts, and macadamia nuts (high in omega-3 fatty acids). Reduce your intake of cashews, peanuts, pine nuts, pumpkin seeds, almonds, and sunflower seeds, which are high in omega-6 fatty acids (linoleic acid = LA).
Avocados and the occasional consumption of olives provide calories and valuable fatty acids.

Fermented foods offer health benefits. Incorporate unpasteurized sauerkraut and kimchi into your diet. Be mindful of the salt content of these foods.

1 g of dried wakame and 1 Brazil nut cover the daily requirement of iodine and selenium. Certain mineral waters contribute to calcium intake.

Depending on the duration of the raw food diet or the amount of raw food consumed, a portion of the diet will consist of cooked food. Incorporate unprocessed foods such as pseudocereals, potatoes, whole grains, and legumes into your meal plan. Sweet potatoes can be eaten cooked or raw. These foods provide calories, carbohydrates, and protein.

Meeting your actual protein needs on a vegan diet is easy. They are significantly lower than advertising suggests. Therefore, daily consumption of legumes is unnecessary. Our article on protein clarifies how much is truly required and why excessive consumption has disadvantages. Reduce your consumption of animal products to a minimum. For health and ethical reasons, complete abstinence is recommended.

More information about raw food

Ernst Erb has described his personal experiences with raw food nutrition in a series of articles and two interviews. These can be found at the following links:

Fundamentals and advanced topics

Interviews with Ernst Erb about vegan raw food

You can switch to raw food for individual meals. We offer around 100 vegan raw food recipes – with tables detailing the essential nutrients they contain. For each recipe, you can click on the individual ingredients and then receive information, ingredient tables, and prices for Germany, Austria, and Switzerland (DACH countries).

The nutrient search provides descriptions of macro- and micronutrients, including amino acids, fatty acids, trace elements, and phytochemicals. More information can be found in the explanatory text: Nutrients Explained Comprehensively.

Discover our book reviews of selected raw food cookbooks and deepen your knowledge about a nutrient-rich raw food diet.

Bibliography - 19 Sources (Link to the evidence)

1.	● Zur Rohkost zählt im weiteren Sinn jedes frische, unerhitzte Lebensmittel pflanzlicher und tierischer Herkunft. Im engeren Sinn ist nur pflanzliche Rohkost gemeint, also eine vegane Variante, bei welcher – je nach Autor – die Schwerpunkte auf Obst, Gemüse, Wildkräuter, Getreide, Nüsse oder Sprossen gelegt werden. Gemeinsam ist allen als Dauerernährung konzipierten Rohkostformen das konsequente Ablehnen gekochter Nahrung oder zumindest eine starke Bevorzugung von Rohkost im Rahmen einer vollwertigen Ernährung. Die verschiedenen Formen der Rohkost-Ernährung unterscheiden sich in der empfohlenen Menge roher Nahrung (70–100 Gewichtsprozent) und im Anteil an tierischen Lebensmitteln. Rohe Nahrung wird als „lebendige Nahrung“ (living food) bezeichnet, während auf mehr als 42 °C erhitzte oder durch Kochen veränderte Nahrung als „tot“ oder „denaturiert“ gilt. Folglich zählen auch Honig, kaltgepresste Pflanzenöle, Trockenfrüchte, kaltgeräucherte Erzeugnisse (Fleisch/Fisch) sowie essig- und milchsaures Gemüse zur Rohkost. Im 19. Jahrhundert machten im deutschsprachigen Raum viele Laien und Ärzte die Erfahrung, dass Rohkost-Diät zur Linderung und Heilung von Krankheiten führen kann. Diese Erkenntnis um die Bedeutung der Rohkost als Therapeutikum führte im Kontext der aufkeimenden Lebensreformbewegung und der sich anbahnenden grossen Krise der Schulmedizin zur Entstehung der ersten grossen Rohkostbewegung, der traditionellen Rohkostbewegung der 1920er- und 1930er-Jahre. In Deutschland sind diesbezüglich an erster Stelle die beiden Brüder Adolf Just (1859–1936) und Rudolf Just (1877–1948) und deren 1896 gegründete Heilanstalt „Jungborn“ im Harz zu nennen. Dort wurden bis zum Zweiten Weltkrieg Tausende Patienten mit einer ausgereiften Methode des Heilfastens und anschliessender Rohkost-Diät behandelt. Der Jungborn war das weltweit erste grosse Zentrum für Heilfasten („Jungborn-Fasten“) sowie für Rohkosttherapie und Vollwert-Ernährung (Semler 2020). In Österreich war es der heute kaum mehr bekannte Arzt Reinhold Schwartz (1880–1967), der in seinem 1922 in Altheim in Oberösterreich eröffneten „Naturheilsanatorium Dr. Schwartz“ mehr als 7000 Patienten mit Heilfasten und Rohkost-Diät therapierte und in vielen Artikeln und Vorträgen davon berichtete (Semler 2019a). Der Schweizer Arzt Max Bircher-Benner (1867–1939) teilte im Jahre 1900 erstmals seine spektakulären Erfolge mit Rohkostbehandlung mit. Diese veranlassten ihn dazu, die heilenden Wirkungen der Rohkost-Diät bei verschiedenen Krankheiten systematisch zu beobachten und zu erforschen. Seine Erfahrungen und Erkenntnisse in seiner Züricher Klinik „Lebendige Kraft“ an mehr als 10.000 Kranken sind in vielen Veröffentlichungen dokumentiert. Es ist besonders dem Engagement von Bircher-Benner zu verdanken, dass sich die medizinisch-wissenschaftliche Forschung in Deutschland Mitte der 1920er-Jahre intensiv mit den physiologischen und therapeutischen Wirkungen roher Nahrung beschäftigte. Die vielen Ärzte der traditionellen Rohkostbewegung setzten strenge Rohkost nur als Therapie ein, passten die Höhe des Rohkostanteils immer dem jeweiligen individuellen Zustand sowie der Psyche des Patienten an und liessen vorab oftmals ein Heilfasten durchführen. Als Dauerernährung rieten sie in der Regel zu einer vollwertigen Ernährung mit einem Rohkostanteil von 50 %, wie er auch in der Vollwert-Ernährung empfohlen wird. Der Zweite Weltkrieg hat dieser Rohkostbewegung ein jähes Ende bereitet und viel wertvolles empirisches Wissen um die Rohkosttherapie geriet schnell in Vergessenheit. In den 1980er- und 1990er-Jahren erschienen vermehrt Rohkost-Bücher, in welchen versucht wird, reine Rohkost-Ernährung als optimale Dauerernährung des Menschen darzustellen. Auffallend in dieser modernen Rohkostbewegung ist, dass es sich bei den Autoren überwiegend um medizinische und naturwissenschaftliche Laien handelt und kaum um Ärzte oder Naturwissenschaftler. Als die moderne Rohkostbewegung in den 2000er-Jahren in Deutschland deutlich nachliess, wurde sie durch den stark aufkommenden Trend zum Veganismus und verschiedene Impulse aus den USA („American way of raw“) neu belebt. Diese jüngste Rohkostbewegung verwendet in Deutschland den Begriff „Rohvolution“. Diese Szene ist von neuen Gesichtern sowie anderer Rhetorik und gemässigterer Zugangsweise geprägt, womit versucht wird, sich vom verstaubten, fanatischen Image der Rohkostbewegung der 1980er- und 1990er-Jahre zu befreien. Ein zentrales Anliegen ist es, zu zeigen, wie aus rohen Lebensmitteln durch kreative Zubereitungstechniken optisch ansprechende und geschmackvolle vegane Gerichte hergestellt werden können. Das erstaunliche medizinische Desinteresse an der Rohkost als Therapie liegt heute zum einen an der in vielen Rohkost-Büchern praktizierten Propaganda, mit der Wissenschaftler und Ärzte nicht in Zusammenhang gebracht werden möchten. Zum anderen lässt sich mit Gemüse, Obst, Nüssen und Co. nicht das grosse Geld verdienen. Hinzu kommt, dass viele Mediziner die Vorstellung, allein mit „Grünzeug“ den Verlauf schwerer Erkrankungen günstig beeinflussen zu können, als zu banal und aufgrund der langsam eintretenden Wirkungen als zu wenig attraktiv bzw. spektakulär empfinden. Buchkapitel DOI: 10.1007/978-3-662-68881-6_13 Book: strong evidence	Semler E. Rohkost. In: Strange R, Leitzmann C, Michalsen A (Ed.). Ernährung und Fasten als Therapie. Berlin, Heidelberg: Springer; 2025:215‑228.
2.	* High consumption of vegetables and fruits is associated with reduced risk for cardiovascular disease. However, little information is available about diets based predominantly on consumption of fruits and their health consequences. We investigated the effects of an extremely high dietary intake of raw vegetables and fruits (70–100% raw food) on serum lipids and plasma vitamin B-12, folate, and total homocysteine (tHcy). In a cross-sectional study, the lipid, folate, vitamin B-12, and tHcy status of 201 adherents to a raw food diet (94 men and 107 women) were examined. The participants consumed ∼1500–1800 g raw food of plant origin/d mainly as vegetables or fruits. Of the participants, 14% had high serum LDL cholesterol concentrations, 46% had low serum HDL cholesterol, and none had high triglycerides. Of raw food consumers, 38% were vitamin B-12 deficient, whereas 12% had an increased mean corpuscular volume (MCV). Plasma tHcy concentrations were correlated with plasma vitamin B-12 concentrations (r = −0.450, P < 0.001), but not with plasma folate. Plasma tHcy and MCV concentrations were higher in those in the lowest quintile of consumption of food of animal origin (P_trend < 0.001). This study indicates that consumption of a strict raw food diet lowers plasma total cholesterol and triglyceride concentrations, but also lowers serum HDL cholesterol and increases tHcy concentrations due to vitamin B-12 deficiency. Querschnittsstudie DOI: 10.1093/jn/135.10.2372 Study: moderate evidence	Koebnick C, Garcia AL, et al. Long-term consumption of a raw food diet is associated with favorable serum LDL cholesterol and triglycerides but also with elevated plasma homocysteine and low serum HDL cholesterol in humans. J Nutr. 2005;135(10):2372-2378.
3.	* Dietary carotenoids are associated with a reduced risk of chronic diseases. Raw food diets are predominantly plant-based diets that are practised with the intention of preventing chronic diseases by virtue of their high content of beneficial nutritive substances such as carotenoids. Therefore, we investigated vitamin A and carotenoid status and related food sources in raw food diet adherents in Germany. Dietary vitamin A, carotenoid intake, plasma retinol and plasma carotenoids were determined in 198 (ninety-two male and 106 female) strict raw food diet adherents in a cross-sectional study. Raw food diet adherents consumed on average 95 weight% of their total food intake as raw food (approximately 1800 g/d), mainly fruits. Raw food diet adherents had an intake of 1301 retinol activity equivalents/d and 16·7 mg/d carotenoids. Plasma vitamin A status was normal in 82 % of the subjects ( ≥ 1·05 μmol/l) and 63 % had β-carotene concentrations associated with chronic disease prevention ( ≥ 0·88 μmol/l). In 77 % of subjects the lycopene status was below the reference values for average healthy populations ( < 0·45 μmol/l). Fat contained in fruits, vegetables and nuts and oil consumption was a significant dietary determinant of plasma carotenoid concentrations (β-carotene r 0·284; P < 0·05; lycopene r 0·168; P = 0·024). Long-term raw food diet adherents showed normal vitamin A status and achieve favourable plasma β-carotene concentrations as recommended for chronic disease prevention, but showed low plasma lycopene levels. Plasma carotenoids in raw food adherents are predicted mainly by fat intake. Querschnittstudie DOI: 10.1017/S0007114507868486 Study: moderate evidence	Garcia AL, Koebnick C, et al. Long-term strict raw food diet is associated with favourable plasma beta-carotene and low plasma lycopene concentrations in Germans. Br J Nutr. 2008;99(6):1293-1300.
4.	* The urinary mercapturic acids N-acetyl-S-(2-carbamoylethyl)-L-cysteine (AAMA) and N-acetyl-S-(2-carbamoyl-2-hydroxyethyl)-L-cysteine (GAMA) are short-term biomarkers of exposure from acrylamide and its metabolite glycidamide, respectively. The medium-term exposure to acrylamide and glycidamide is monitored by the adducts N-(2-carbamoylethyl)-Val (AA-Val) and N-(2-carbamoyl-2-hydroxyethyl)-Val (GA-Val) in hemoglobin (Hb), respectively. two diet studies including 36 omnivores, 36 vegans and 16 strict raw food eaters (abstaining from any warmed or heated food for at least four months) Median urinary AAMA excretion per day in non-smoking omnivores, vegans and raw food eaters were 62.4, 85.4 and 15.4 µg/day, respectively; the corresponding median AA-Val levels were 27.7, 39.7 and 13.3 pmol/g Hb, respectively. Median levels in strict raw food eaters were about 25% (AAMA excretion) and 48% (AA-Val) of those in omnivores. In comparison to 2017, AAMA and GAMA excretion levels were hardly altered in 2021, however, levels of AA-Val and GA-Val in 2021 slightly increased. There was a weak correlation between AAMA excretion levels determined four years apart (r_S = 0.30), and a moderate correlation between levels of AA-Val (r_S = 0.55) in this timeframe. Our data in strict raw food eaters confirm a significant endogenous formation to acrylamide in a size range, which is—based on the levels of AA-Val—distinctly higher than reported previously based on levels of urinary AAMA excretion. The relatively lower AAMA excretion in raw food eaters likely represents a lower extent of glutathione conjugation due to missing hepatic first-pass metabolism in case of endogenous formation of acrylamide, which leads to a higher systemic exposure. Querschnittstudie DOI: 10.1007/s00204-024-03798-z Study: moderate evidence	Monien BH, Bergau N, et al. Internal exposure to heat-induced food contaminants in omnivores, vegans and strict raw food eaters: biomarkers of exposure to acrylamide (hemoglobin adducts, urinary mercapturic acids) and new insights on its endogenous formation. Arch Toxicol. 2024;98(9):2889-2905.
5.	* Endurance sport requires a healthy and balanced diet. In this case report we present the findings of an ultra-triathlete (three times Ironman, means 11.4 km swim, 540 km bike, 125 km run in 41:18 h as a whole) living on a raw vegan diet and having finished the competitions under these nutritional conditions. To this end, the vegan ultra triathlete and a control group of 10 Ironman triathletes of similar age living on a mixed diet were investigated, using echocardiography and spiroergometry. In addition, blood samples were taken from the vegan athlete both in the sporting season and in the off-season. The vegan athlete showed no signs of dietary deficiencies or impaired health. In comparison with the control group, the vegan athlete showed a higher oxygen intake at the respiratory compensation point. This case demonstrates that even top-class sporting performance, like that of a three-time Ironman, is possible on a vegan diet. Whether a vegan diet offers advantages or disadvantages for the performance of endurance athletes remains an open question. A 48-year-old male finished Triple-Ironman distance in 41 hours and 18 minutes (11.4 km swimming, 540 km cycling, and 126 km running). At the time of the examinations, he had been practising his current diet of raw vegan diet for 6 years. Prior to this, the vegan athlete had been living as a vegan for 3 years and as a vegetarian for the previous 13 years. All last competitions were performed only based on a raw diet. Fallbericht DOI: 10.1155/2014/317246 Study: weak evidence	Leischik R, Spelsberg N. Vegan triple-ironman (raw vegetables/fruits). Case Rep Cardiol. 2014;2014:317246.
6.	* English-speaking attendees at Hippocrates Health Institute (Florida, US), a raw vegan institute, were recruited on arrival and typically stayed 1–3 weeks. Of 107 attendees eligible for the questionnaire study and 82 for the blood marker substudy, 51 and 38 participants, respectively, provided complete follow-up data. Overall QOL improved 11.5% (p = 0.001), driven mostly by the mental component. Anxiety decreased 18.6% (p = 0.009) and perceived stress decreased 16.4% (p < 0.001). Participants’ ratings of the food's taste were unchanged, but their ratings of how well they were taking care of themselves improved. CRP, lymphocytes, T cells, and B cells did not change significantly, but CD4, CD8, and NK cells decreased slightly. A stay at a raw vegan institute was associated with improved mental and emotional QOL. Studies are needed to determine the feasibility of conducting a clinical trial of the raw vegan diet among healthy people, and subsequently among patients with specific diseases. Prospektive Beobachtungsstudie (longitudinal) DOI: 10.1016/j.ctim.2008.02.004 Study: moderate evidence	Link LB, Hussaini NS, Jacobson JS. Change in quality of life and immune markers after a stay at a raw vegan institute: a pilot study. Complement Ther Med. 2008;16(3):124-130.
7.	* The purpose of this study was to evaluate adherence and identify predictors of adherence to a raw vegan diet (i.e., uncooked plant foods) following a stay at a raw vegan institute. In this cohort study of guests at a raw vegan institute, subjects completed written questionnaires upon arrival and 12 weeks later. Of 107 eligible guests, 84 participated. Mean age was 54 years, 23 were male, and 73 white. Fifty-one completed the 12-week follow-up. Eight (16%) reported their diet to be ⩾80% raw vegan at baseline and 14 (28%) at follow-up. Based on a raw vegan dietary adherence score (range 0–42) created for this study, mean adherence (SD) increased from 15.1 (5.4) to 17.0 (5.8) over 12 weeks (). Baseline predictors of adherence included: education (), severity of disease , and self-efficacy to adhere . Future interventions that evaluate this diet should address self-efficacy, an important, potentially remediable predictor of adherence. Kohortenstudie DOI: 10.1016/j.ctcp.2006.12.005 Study: moderate evidence	Link LB, Jacobson JS. Factors affecting adherence to a raw vegan diet. Complement Ther Clin Pract. 2008;14(1):53-59.
8.	* To examine the relationship between the strictness of long-term raw food diets and body weight loss, underweight and amenorrhea. In a cross-sectional study 216 men and 297 women consuming long-term raw food diets (3.7 years; SE 0.25) of different intensities completed a specially developed questionnaire. Participants were divided into 5 groups according to the amount of raw food in their diet (70–79, 80–89, 90–94, 95–99 and 100%). A multiple linear regression model (n = 513) was used to evaluate the relationship between body weight and the amount of raw food consumed. Odds of underweight were determined by a multinomial logit model. From the beginning of the dietary regimen an average weight loss of 9.9 kg (SE 0.4) for men and 12 kg (SE 0.6) for women was observed. Body mass index (BMI) was below the normal weight range (< 18.5 kg/m²) in 14.7% of male and 25.0% of female subjects and was negatively related to the amount of raw food consumed and the duration of the raw food diet. About 30% of the women under 45 years of age had partial to complete amenorrhea; subjects eating high amounts of raw food (> 90%) were affected more frequently than moderate raw food dieters. Conclusions: The consumption of a raw food diet is associated with a high loss of body weight. Since many raw food dieters exhibited underweight and amenorrhea, a very strict raw food diet cannot be recommended on a long-term basis. Querschnittstudie DOI: 10.1159/000012770 Study: moderate evidence	Koebnick C, Strassner C, et al. Consequences of a long-term raw food diet on body weight and menstruation: results of a questionnaire survey. Ann Nutr Metab. 1999;43(2):69-79.
9.	* In this cross-sectional study, we compared 16 non-smoking strict raw food eaters (5 women and 11 men, age 44.6 ± 12.3 years, duration of following the diet 11.6 ± 10.8 years) with the non-smoking participants (32 vegans, 27 omnivores) of the “Risk and Benefits of a Vegan Diet” (RBVD) study. We investigated body composition, dietary intake from 3-day weighed food records, and relevant fasting blood and serum parameters. Food choice and dietary behavior were very heterogenic in raw food eaters. They had lower mean values of BMI and percentage of body fat than the respective RBVD participants. The same holds true for energy supply and intakes of protein, carbohydrate, calcium and iodine. Serum levels revealed lower levels of HDL cholesterol, triglycerides, zinc, and vitamin D3. The raw food eaters with (n = 9) and without (n = 7) supplementation of vitamin B12 had median vitamin B12 levels of 399 and 152 ng/L, respectively. Accordingly, eight raw food eaters (50%) had homocysteine levels above 12 µmol/L. The study allows a close look at strict raw food eaters with respect to possible dietary deficiencies, but also provides insights into motivations and daily life. The 16 strict raw food eaters were compared to non-smoking vegans (n = 32) and omnivores (n = 27) not avoiding the heating of food. These “control” subjects were participants of the “Risk and Benefits of a vegan diet” (RBVD) study also performed at the BfR (in 2017), and had to follow their diet for at least one year. In the RBVD study, an omni-vorous diet was defined as at least three servings of meat or two servings of meat and two servings of sausages a week. Detailed information about the RBVD study was published elsewhere. Querschnittstudie DOI: 10.3390/nu14091725 Study: moderate evidence	Abraham K, Trefflich I, et al. Nutritional Intake and Biomarker Status in Strict Raw Food Eaters. Nutrients. 2022;14(9):1725.
10.	* The aim of the current study was to conduct a systematic literature review of the available evidence to assess and investigate the effects of a raw vegetarian diet with a review of clinical trial studies. The literature search to find related studies were performed through three scientific databases, including PubMed, SCOPUS, and Google Scholar with related keywords. Based on our findings from the literature, a raw vegan diet with more than 90% raw food cannot be recommended for a long time due to micronutrient deficiencies as well as related complications. In order to investigate possible advantages and disadvantages, it seems well-designed clinical trials are necessary to clarify these effects. It seems that raw vegan diet has disadvantages such as the inactivation of toxins and pesticides and contamination with microorganisms due to insufficient heating and insufficient intake of some nutrients such as protein, vitamin B12, iron, calcium, selenium, zinc, omega-3 fats, and vitamin D. The increase in tHcys is related to low B12 intake in these patients. Urine MMA assay has been shown to be much more effective than serum cobalamin in identifying raw vegans at risk for vitamin B12 deficiency and monitoring the improvement of cobalamin status. Early detection and supplementation are the best way to prevent permanent neurological damage and disorders. The occurrence of amenorrhea in women on a raw vegan diet is also a sign of functional problems in the long-term following of such a diet. Narratives Review DOI: 10.1016/j.nutos.2023.04.001 Study: weak evidence	Pahlavani N, Azizi-Soleiman F. The effects of a raw vegetarian diet from a clinical perspective; review of the available evidence. Clinical Nutrition Open Science. 2023;49:107-112.
11.	* We performed a cross-sectional study on 18 volunteers (mean ± SD age, 54.2 ± 11.5 years; male/female ratio, 11:7) on a RF vegetarian diet for a mean of 3.6 years and a comparison age- and sex-matched group eating typical American diets. We measured body composition, bone mineral content and density, bone turnover markers (C-telopeptide of type I collagen and bone-specific alkaline phosphatase), C-reactive protein, 25-hydroxyvitamin D, insulin-like growth factor 1, and leptin in serum. The RF vegetarians had a mean ± SD body mass index (calculated as weight in kilograms divided by the square of height in meters) of 20.5 ± 2.3, compared with 25.4 ± 3.3 in the control subjects. The mean bone mineral content and density of the lumbar spine (P= .003 and P<.001, respectively) and hip (P = .01 and P<.001, respectively) were lower in the RF group than in the control group. Serum C-telopeptide of type I collagen and bone-specific alkaline phosphatase levels were similar between the groups, while the mean 25-hydroxyvitamin D concentration was higher in the RF group than in the control group (P<.001). The mean serum C-reactive protein (P = .03), insulinlike growth factor 1 (P = .002), and leptin (P = .005) were lower in the RF group. Querschnittstudie DOI: 10.1001/archinte.165.6.684 Study: moderate evidence	Fontana L, Shew JL, et al. Low bone mass in subjects on a long-term raw vegetarian diet. Arch Intern Med. 2005;165(6):684-689.
12.		Biesalski HK, Grimm P. Taschenatlas der Ernährung. 3. Auflage. Georg Thieme Verlag: Stuttgart und New York. 2004.
13.	* The aim of the study was to investigate the frequency and severity of dental erosions and its association with nutritional and oral hygiene factors in subjects living on a raw food diet. As part of a larger dietary study 130 subjects whose ingestion of raw food was more than 95% of the total food intake were examined. The median duration of the diet was 39 (minimum 17, maximum 418) months. Before the clinical examination, the participants answered questionnaires and recorded their food intake during a 7–day period. Dental erosions were registered using study models. As a control 76 sex– and age–matched patients from our clinic were randomly selected. The raw food diet records showed the median daily frequency of ingesting citrus fruit to be 4.8 (minimum 0.5, maximum 16.1). The median intake of fruit was 62% (minimum 25%, maximum 96%) of the total, corresponding to an average consumption of 9.5 kg of fruit (minimum 1.5, maximum 23.7) per week. Compared to the control group subjects living on a raw food diet had significantly (p≤0.001) more dental erosions. Only 2.3% of the raw food group (13.2% of the controls) had no erosive defects, whereas 37.2% had at least one tooth with a moderate erosion (55.2% of the controls) and 60.5% had at least one tooth with a severe erosion (31.6% of the controls). Within the raw food group no significant correlation was found between nutrition or oral health data and the prevalence of erosions. Nevertheless, the results showed that a raw food diet bears an increased risk of dental erosion compared to conventional nutrition. Querschnittstudie DOI: 10.1159/000016498 Study: moderate evidence	Ganss C, Schlechtriemen M, et al. Dental erosions in subjects living on a raw food diet. Caries Res. 1999;33(1):74-80.
14.	* Macronutrients and micronutrients present in different types of diet could influence different aspects of both inflammatory and immune responses; thereby, diets could influence oral health and the periodontal condition. The raw vegan diet is a subset of vegetarianism in which only uncooked plant-derived foods are consumed. The present study's aim was to evaluate the effect of the raw vegan diet on periodontal and dental health parameters. A total of 118 participants (59 raw vegans and 59 controls) were interviewed about their level of education and oral health habits. Samples of unstimulated whole saliva were collected for pH analysis, and dental and periodontal parameters were examined. Then, statistical analysis was performed. Raw vegans had better oral hygiene (P = 0.001). The decayed-missing-filling indices were relatively equal in both groups. The probing depth, bleeding on probing (BOP), and simplified oral hygiene index were significantly lower in raw vegans (P = 0.047, P = 0.017, and P = 0.001, respectively). Multiple regression analyses disclosed that probing depth and BOP were significantly related to debris index. Based on this study's results, it can be presumed that the better periodontal condition in raw vegans is a result of their better oral care and lifestyle. Querschnittstudie DOI: 10.4103/tcmj.tcmj_161_19 Study: moderate evidence	Atarbashi-Moghadam F, Moallemi-Pour S, et al. Effects of raw vegan diet on periodontal and dental parameters. Tzu Chi Med J. 2020;32(4):357-361.
15.	● Book: strong evidence	Semler E. Rohkost: Historische, therapeutische und theoretische Aspekte einer alternativen Ernährungsform [Dissertation]. Giessen: Justus-Liebig-Universität Giessen; 2006.
16.	* Thermal treatment affects both the cell wall and carotenoid content of plants, in turn altering their bioavailability. Aschoff et al. [27] demonstrated that the bioavailability of β-cryptoxanthin, zeinoxanthin and lutein in pasteurized orange juice is higher than in fresh orange juice. In contrast, Vimala et al. [28] evaluated carotenoid content in sweet potato undergoing different treatments (cooking, frying, oven-drying, and sun-drying). Oven-drying (50–60 °C) maintained 90% of β-carotene in sweet potato compared to the fresh product, whereas all other treatments decreased carotenoid content between 15% and 30%. Odriozola-Serrano et al. [29] examined the effect of pasteurization and electrical pulses on the carotenoid content of tomato juice. They found that tomato juice treated with electrical pulses had a higher carotenoid content. Thus, pulse treatment is the most efficient method of preserving carotenoid content and increasing their bioavailability compared to the traditional treatment. In all previously cited examples, there is a decrease in total carotenoid content; nevertheless, the bioavailability of carotenoids improves by reducing dietary fiber, releasing cellular content, softening plant material, and reducing the interactions between carotenoids and other food components. Thus, promoting both the release of carotenoids and formation of micelles helps increase their absorption. Narratives Review DOI: 10.3390/plants12020313 Study: weak evidence	González-Peña MA, Ortega-Regules AE, Anaya De Parrodi C, Lozada-Ramírez JD. Chemistry, Occurrence, Properties, Applications, and Encapsulation of Carotenoids—A Review. Plants. 2023;12(2):313.
17.	* The results of the present study show that long-term consumption of a low-calorie lowprotein vegan diet or regular endurance exercise training is associated with a decrease in multiple risk factors for CHD. Moreover, eating a low-calorie low-protein vegan diet, which is low in sodium and high in fiber and potassium, might have greater beneficial effects on blood pressure than endurance exercise, independent of adiposity. Querschnittsstudie mit Kontrollgruppe DOI: 10.1089/rej.2006.0529 Study: moderate evidence	Fontana L, Meyer TE, Klein S, Holloszy JO. Long-Term Low-Calorie Low-Protein Vegan Diet and Endurance Exercise are Associated with Low Cardiometabolic Risk. Rejuvenation Research. 2007;10(2):225–234.
18.	* Methodik Zur Erfassung des Ernährungs- und Gesundheitsverhaltens von Rohköstlern wurde im Rahmen der Giessener Rohkost-Studie ein umfangreicher Fragebogen entwickelt. Neben soziodemografischen Daten wurden u. a. Informationen zu folgenden Themen erfragt: Gesundheitszustand vor und während der Rohkost-Ernährung, gesundheitsbezogenes Verhalten, Ernährungsverhalten, Begründung und Einstellung zur Ernährungsweise [8]. Dieser Fragebogen wurde im Jahre 2003 modifiziert und an die 201 Teilnehmer des Endkollektivs der Giessener Rohkost-Studie (1993/94) versandt, von denen 116 antworteten (Rücklaufquote: 57,7 %). In 27 Fällen (13,4 %) kam die Postsendung ungeöffnet zurück: die aktuelle Adresse konnte aber nicht ermittelt werden. Von 48 Personen (23,9 %) wurde der Fragebogen nicht ausgefüllt, 10 Personen (5 %) waren bereits verstorben. Von den 116 befragten Personen gaben 43 an, keine Rohkost-Ernährung mehr zu praktizieren (d. h. Rohkostanteil < 70 %). Für die deskriptive Auswertung der verbliebenen 73 Fragebögen wurde das Statistikprogramm SPSS 12.0 für Windows verwendet. Narratives Review Study: weak evidence	Semler E. Rohkost-Ernährung. Eine Untersuchung von Langzeit-Rohköstlern. Ernährungs-Umschau. 2008;5:280-289.
19.	* Unser derzeitiges Verständnis der menschlichen Verdauungsspezialisierung im Vergleich zu anderen Primaten beschränkt sich jedoch weitgehend auf anatomische und weniger auf physiologische Merkmale, wie die Verkleinerung von Mund, Zähnen, Magen und Dickdarm. Obwohl diese Veränderungen stark auf eine Anpassung an leicht zu kauende und schnell verdauliche Nahrung hindeuten, treffen diese Beschreibung auch auf einige Rohkostprodukte zu, beispielsweise Früchte, Knochenmark, Hirn, Leber, Honig und bestimmte Lebensmittel wie Samen, die von einer nicht-thermischen Verarbeitung deutlich profitieren. Gene, die bei Mäusen, die mit rohem bzw. gekochtem Fleisch gefüttert wurden, unterschiedlich exprimiert waren, zeigten fast ausschliesslich bei der Rohfleischdiät eine Hochregulation. Diese Gene waren stark mit Genen angereichert, die mit dem Immunsystem in Zusammenhang stehen. Dies stützt die weit verbreitete, aber wenig belegte Annahme, dass das Kochen von Fleisch eine kostspielige Immunantwort verhindert ( Ragir 2000 ; Carmody und Wrangham 2009 ). Die spezifischen Auslöser der Immun-Hochregulation bei der Rohfleischdiät sind jedoch weiterhin unklar. Bei Knollen stellten wir fest, dass Gene, die am Kohlenhydratstoffwechsel beteiligt sind, bei gekochten Knollen im Vergleich zu rohen Knollen weniger stark exprimiert wurden. Dies deckt sich mit etablierten Forschungsergebnissen, die zeigen, dass Kochen die Kohlenhydratverdauung durch Verkleisterung der Stärke verbessert. Experimentell-genomische und evolutionsbiolgische Studie DOI: 10.1093/gbe/evw059 Study: weak evidence	Carmody RN, Dannemann M, Briggs AW, Nickel B, Groopman EE, Wrangham RW, Kelso J. Genetic Evidence of Human Adaptation to a Cooked Diet. Genome Biol Evol. 2016;8(4):1091-103.
We have categorized studies and books on nutrition and health according to the following 3 evidence categories: green = strong evidence, yellow = medium evidence, purple = weak evidence. The remaining sources are marked ingray . You can find a detailed explanation in our article: Science or Belief? How to evaluate publications..

Author: Ernst Erb | 20 May 2026