Turmeric is mainly known for its brilliant color. It is used in cooking to achieve a yellow color and also in other areas to dye certain materials such as paper.
From Wikipedia: “Turmeric is a rhizomatous herbaceous perennial plant (Curcuma longa) of the ginger family, Zingiberaceae. It is native to southern Asia, requiring temperatures between 20 and 30 °C (68 and 86 °F) and a considerable amount of annual rainfall to thrive. Plants are gathered annually for their rhizomes and propagated from some of those rhizomes in the following season.
When not used fresh, the rhizomes are boiled for about 30–45 minutes and then dried in hot ovens, after which they are ground into a deep-orange-yellow powder commonly used as a coloring and flavoring agent in the cuisines of Bangladesh, India, Indonesia, Iran and Pakistani cuisine, especially for curries, as well as for dyeing.
Although long-used in Ayurvedic medicine to treat various diseases, there is little high-quality clinical evidence for use of turmeric or its main constituent, curcumin, as a therapy.”
“Turmeric grows wild in the forests of South and Southeast Asia. It is one of the key ingredients in many Asian dishes. Indian traditional medicine, called Siddha, has recommended turmeric for medicine. Its use as a coloring agent is not of primary value in South Asian cuisine.
Turmeric is mostly used in savory dishes, but is used in some sweet dishes, such as the cake sfouf. In India, turmeric plant leaf is used to prepare special sweet dishes, patoleo, by layering rice flour and coconut-jaggery mixture on the leaf, then closing and steaming it in a special copper steamer (goa).
In recipes outside South Asia, turmeric is sometimes used as an agent to impart a golden yellow color. It is used in canned beverages, baked products, dairy products, ice cream, yogurt, yellow cakes, orange juice, biscuits, popcorn color, cereals, sauces, gelatins, etc. It is a significant ingredient in most commercial curry powders. ...
Although typically used in its dried, powdered form, turmeric is also used fresh, like ginger. It has numerous uses in East Asian recipes, such as pickle that contains large chunks of soft turmeric, made from fresh turmeric.”
“Turmeric also is used to give a yellow color to some prepared mustards, canned chicken broths, and other foods (often as a much cheaper replacement for saffron).”
“Turmeric stimulates the production of gastric juices ... The yellow pigment found in some Curcuma species, curcumin being a prime example, have cancer-inhibiting, antioxidant, and anti-inflammatory effects on ...
Research findings suggest that curcumin may contribute to the degradation of the tumor suppressor protein p53 and therefore promote the "growing" of p53-controlled cancer cells. ... Research studies providing scientific proof of these mechanisms has not yet been performed on human subjects.
Curcumin works by inhibiting the enzymes cyclooxygenase-2, lipoxygenase, and the inflammation-inhibiting NO-synthase. This effect of curcumin has been demonstrated, for example, in patients with knee arthrosis. The reduction of inflammation is also thought to be the cause of the cancer-inhibiting effect.
The cancer-inhibiting effects of turmeric have been shown in several studies: it can repress colon polyps and as a result prevent colon cancer as shown in a study with patients with familial adenomatous polyposis (in this hereditary disease, hundreds of polyps are formed in the intestine, which develops into colorectal cancer when left untreated). Taking curcumin reduced the number of polyps by 60 percent. The size of the remaining polyps decreased on average by 50 percent. In addition, curcumin can inhibit the formation and spread of metastases in breast cancer. Scientists from the University of Texas in Houston discovered this in experiments with mice. The substance obtained from turmeric proved to be particularly effective in combination with the active ingredient "paclitax..", a common drug used to treat breast cancer. Some epidemiological studies also show an anticancer potential and thus a possible chemopreventive effect in prostate cancer.
Curcumin also obviously supports bone health: it lowers the concentration of the RANK ligand ... As a result of the first-pass effect, the bioavailability of curcumin is low. Microemulsions increase bioavailability from approximately 350% (Meriva) to 5000% (Arantal, D: Curcuflex).*”
Research results about curcumin:
“Claims that curcumin in turmeric may help to reduce inflammation have not been supported by strong studies.
Turmeric or its principal constituent, curcumin, has been studied in numerous clinical trials for various human diseases and conditions, but the conclusions have either been uncertain or negative.”
“Turmeric should be stored in a dark place and not for very long, as the color fades quickly with exposure to light, and it loses its aroma.”
Note (italics): * = Translation from a German Wikipedia entry