It's important to know that the vast majority of studies on turmeric have not examined the spice itself, but rather one of its constituents called curcumin. When you hear about the benefits of turmeric on a website or on a health news report on television, you are mostly likely hearing about the benefits of curcumin. This aspect of the health research can be very confusing!
On the one hand, curcumin is a polyphenol in turmeric with a quite remarkable set of potential health benefits. These potential benefits include better regulation of inflammation, oxidation, cell signaling, blood sugar levels, blood fat levels, and brain levels of the omega-3 fatty acid called DHA (docosahexaenoic acid), among its many benefits. But at the same time, there are many other health-supportive substances in turmeric, and the amount of curcumin in turmeric root can be fairly small. The actual amount of curcumin in turmeric varies from species to species, growing conditions, and timing of growth and harvest. But it typically accounts for only 2-5% of the root weight and can drop even lower under some conditions. In short, we are delighted to see great studies on the health benefits of curcumin, yet since we are most interested in the spice itself (turmeric) and the potential benefits of this spice in recipes, we also realize that some of the research on curcumin doesn't easily translate into these more practical kitchen and recipe applications. In the remainder of this Health Benefits section, we want to tell you about practical health benefits of turmeric in cooking based on our confidence in research about the spice itself.
The vast majority of studies on turmeric and cancer risk have been conducted on rats and mice. In addition, the research interventions have involved curcumin rather than turmeric. Normally, we would not try to draw any conclusions about food and your health from animal studies on isolated food constituents! But in this case, we feel justified in making an exception due to the large number of animal studies, the consistency of the findings, and the diverse number of mechanisms that allow curcumin to lower cancer risk in rats and mice. These mechanisms include: antioxidant mechanisms, anti-inflammatory mechanisms, immuno-regulatory mechanisms, enzyme-related mechanisms, cell signaling mechanisms, and cell cycle mechanisms. As you can surmise, we're talking about a remarkable range of potential anti-cancer impacts with respect to curcumin intake.
In addition, animal studies on curcumin have looked at a wide variety of cancer forms, including cancer of the prostate, pancreas, lung, colon, cervix, breast, mouth, tongue, and stomach. At WHFoods, our research presentation policy is to avoid extrapolating from animal studies to human diets. We like to see large-scale studies on humans eating everyday foods before we post information on our website about the health benefits of particular foods. However, in this case we would like to make an exception. Even though we do not have large-scale studies on humans consuming turmeric, the repeatedly positive findings in these animal studies on curcumin convince us that you can lower your overall cancer risk through regular consumption of turmeric.
Of special interest in the cancer research on curcumin has been its well-documented role in detoxification. In animal studies, curcurmin has consistently been shown to stimulate Phase II detox activity. This phase of detoxification allows our cells to bind potential toxins together with other molecules so that they can be excreted from the body. As more and more potentially toxic substances get bound together with other molecules during Phase II processing, our risk of cancer development decreases. Research interest in curcumin and turmeric also extends into other components of detoxification, and we look forward to future studies that will help to clarify the unique role of this spice in cellular detoxification.
It's been especially interesting to follow research on curcumin and cancers of the digestive tract. This component of turmeric has a relatively low level of absorption from the digestive tract. Less absorption might logically sound like an unwanted event that would provide fewer health benefits. However, less absorption from the gut up into the body might also mean more curcumin remaining inside the digestive tract, allowing it to provide health benefits in that location. Studies have shown that curcumin is relatively stable at stomach pH (the unit of measurement for acidity) and this stability means that curcumin might be able to pass through the stomach and onward through our intestines intact. Several animal studies actually show this result to occur, and they also show curcumin's ability to influence cell signaling in our intestines. In animal studies, this influence on cell signaling in the lower digestive tract has been linked to improvement in inflammatory conditions like colitis. This same set of events is under active study with respect to other chronic bowel problems as well as colorectal cancer.
Inclusion of turmeric as a spice in a recipe can help regulate blood fat levels after a meal. Studies show that the activity of certain enzymes (including pancreatic lipase and phospholipase A2) can be inhibited by incorporation of turmeric into recipes, with a result of lower blood triglycerides following meal intake. In the studies that we have reviewed, turmeric was not used by itself, but together with other spices including ginger, garlic, black pepper, cinnamon, and clove. One particular interesting result in one study was the role of stress in altering turmeric benefits. In this study, lowered levels of blood triglycerides were only seen when study participants stayed relaxed following their turmeric-containing meals. However, if the participants became engaged in stressful activities after their meals, blood triglyceride levels were not reduced by the turmeric-containing meals.
The anti-inflammatory and antioxidant effects of curcumin have been associated with improved regulation of blood pressure and decreased risk of several types of cardiovascular disease in animals. There are also cholesterol-lowering studies in animals given supplemental curcumin, but the amounts of curcumin required to see results in these studies raise questions for us about the applicability of these studies to turmeric as a spice in recipes. That's because 500 milligrams of curcumin is a representative dose in these cholesterol studies as a whole, and that amount would require the intake of about 7 teaspoons of turmeric per day if the plant root used to produce the powdered and dried spice contained 5% curcumin by weight.
In animal studies, increased interest has been shown in the potential for turmeric to improve chronic digestive health problems including Crohn's disease, ulcerative colitis, and inflammatory bowel disease. Most of the proposed mechanisms of actions in these studies involve changes in cell signaling and decreased production of pro-inflammatory cytokines.
Rheumatoid and other types of arthritis have also been active areas of animal study on curcumin. Once again, most of the science interest here has been in decreased production of pro-inflammatory messaging molecules.
Improved cognitive function has also been an area of increased research interest. Here one fascinating focus has been on the ability of curcumin to stimulate production of DHA (docosahexaenoic acid) from ALA (alpha-linolenic acid). Both ALA and DHA are omega-3 fatty acids with a wide range of proven health benefits, but DHA has been shown to be especially important in nervous system function both in the brain and throughout the body. (There is more DHA in the brain than any other single type of fatty acid, and when DHA circulates around our body, the brain receives a higher percentage of this fatty acid than any other single organ.)
A fairly large number of foods contain small to moderate amounts of ALA. However, it is more difficult to get significant amounts of pre-formed DHA from food. (The best sources of pre-formed DHA on our website are fish, especially salmon and sardines.) Fortunately, under the right circumstances, our bodies can make DHA from ALA using enzymes called desaturases and elongases. It's precisely these enzymes that curcumin can stimulate in their activity, increasing the likelihood of more DHA production—and along with it, improved brain function in areas especially reliant on DHA. Given this set of events, it has not been surprising to see more animal studies focusing on the ability of curcumin and turmeric to potentially improve chronic neurodegenerative problems including Alzheimer's disease.
Finally, as mentioned in our What's New and Beneficial section, use of turmeric as a recipe spice has been shown to lower loss of beta-carotene in certain cooked foods. The best study that we have seen in this area involved the use of turmeric in the cooking of carrots and pumpkin. Also studied were amaranth and the leaves of a vegetable commonly called drumstick (Moringa oleifera). It was the antioxidant properties of numerous compounds in turmeric that researchers pointed to as the mostly likely cause of better beta-carotene preservation.
Before leaving this Health Benefits section, it is worth noting that recent studies show the breakdown products of curcumin to be as potentially helpful as curcumin itself. These breakdown products include vanillin and ferulic acid—two well-studied antioxidant and anti-inflammatory compounds. The role of curcumin breakdown products puts even further emphasis on the unique potential for turmeric health benefits inside the digestive tract where this breakdown process would initially occur.
The dried powdered spice that many people use in recipes comes from the root (rhizome) portion of the plant Curcuma longa. The unprocessed form of this root bears a strong resemblance to ginger root, and that resemblance is not a coincidence! Turmeric, ginger, and cardamom are plants all belonging to the Zingiberaceae family—also known as the ginger family. You'll sometimes hear turmeric being referred to as Indian saffron since its deep yellow-orange color is similar to that of saffron. You'll also sometimes hear it being referred to as curcuma, after it's best-studied polyphenolic component, namely, curcumin. Turmeric has been used throughout history as a culinary spice, herbal medicine, and fabric dye.
Turmeric root has a very interesting taste and aroma. Its flavor is peppery, warm, and bitter while its fragrance is mild yet slightly reminiscent of orange and ginger.
Consumers in the U.S. are mostly familiar with the dried, powdered form of turmeric and its unique and unforgettable color. When purchased in fresh root form, however, turmeric looks quite similar to ginger root, even though when cut open, its flesh is vibrant orange and dramatically different from the color of cut ginger root.
Turmeric is native to India and Southeast Asia, where it has been popular in cuisines for several thousand years. In addition to its culinary use, turmeric has remained a mainstay herb in botanical medicine, with medical usage going back thousands of years in the Ayurvedic tradition. In the U.S., turmeric is a substance that is included on the GRAS List (Generally Recognized As Safe) by the U.S. Food and Drug Administration where it is considered as a natural food coloring agent.
On a worldwide basis, about 800,000 tons of turmeric are produced each year, with over 75% of this total amount coming from India, which is also the world's largest consumer and exporter of turmeric; in terms of exports, over 50% of all global exports come from this country. After India, the greatest turmeric production currently occurs in Bangladesh, Pakistan, Sri Lanka, Taiwan, China, Myanmar, and Indonesia. Turmeric is also grown commercially in many Central and South American countries.
Even through dried herbs and spices are widely available in supermarkets, explore the local spice stores or ethnic markets in your area. Oftentimes, these stores feature an expansive selection of dried herbs and spices that are of superior quality and freshness than those offered in regular markets. Just like with other dried spices, try to select organically grown turmeric since this will give you more assurance that the dried, powdered herb has not been irradiated. Since the color of turmeric varies among varieties, it is not a strict criterion for quality.
We would also note that fresh turmeric root is also becoming more widely available to consumers. You'll usually find this form of turmeric in the produce section, sometimes near the ginger root. Many people report enjoying this form of turmeric in soups, salads, and dressings or marinades. If you bring this form of turmeric home from the grocery, it should be stored in the refrigerator.
Be sure not to confuse turmeric with curry. "Curry" is a very generalized name for spice combinations that typically contain turmeric alongside of numerous other spices. For example, a dried powdered curry powder may often contain turmeric, coriander, cumin, ginger, cardamom, cinnamon, and clove, along with other spices like nutmeg or fenugreek.
Dried turmeric powder should kept in a tightly sealed container in a cool, dark and dry place. And as mentioned earlier, fresh turmeric rhizome (root) should be kept in the refrigerator.
For some of our favorite recipes, click Recipes.
GI: very low
|vitamin B6||0.08 mg||5||5.4||good|
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Density>=3.4 AND DRI/DV>=5%
Density>=1.5 AND DRI/DV>=2.5%