Briefly about Curcumin
Curcumin is produced from the spice turmeric, and numerous clinical studies have shown that it has many proven and promising health benefits. In particular, studies show that curcumin acts as an antioxidant. It also has been shown to act as an anti-inflammatory in humans, although more studies are needed to demonstrate that curcumin is effective in treating chronic inflammatory conditions like rheumatoid arthritis. Curcumin also may help prevent certain types of cancer and reverse symptoms of Alzheimer’s disease.
Curcumin is not very bioavailable in its natural form. However, it can be taken as a supplement, several of which have been specially formulated for increased bioavailability and absorption. Some manufacturers add black pepper extracts like piperine to achieve this effect. However, this is an irritant for some people. Phospholipid addition (as in the Meriva formulation) has been shown to be more effective and non-irritating.
When choosing a curcumin supplement, remember the following:
- Check the concentration on the label – you want to maximize the amount of active curcuminoids per serving
- Look for products in the Meriva or Theracurmin formulation as these have been specially developed to measurably increase concentration and bioavailability of curcumin and have been used in research trials
- Choose a product that contains phospholipids to increase absorption
- Take your curcumin supplement with a meal that contains fat for better absorption
- Select a high-quality brand in order to avoid impurities, toxins, and fillers
- You will likely want to consumer 500mg or more per day to make an impact
- Check with your doctor about potential negative drug interactions, if you’re taking any
A Closer Look at Curcumin
Curcumin is a compound derived from turmeric, a spice that comes from the roots of a tropical plant called the Curcuma longa. Curcumin is thought to be the most biologically active part of turmeric and has been used in traditional Chinese and East Indian medicine for more than four millennia to reduce inflammation, aid digestion, treat wounds, and alleviate skin conditions. Some countries and regions – particularly India, Southeast Asia, and the Middle East – also use it for cooking. For example, the taste and yellow color of curry, along with the color of some mustards and cheeses, come from curcumin.[1, 2]
There are a number of studies showing that curcurmin has anti-inflammatory, anti-oxidant, anticancer, and other beneficial properties. Generally speaking, curcumin’s benefits come from regulating transcription factors, inflammatory cytokines, protein kinases, and other molecular targets in various ways. However, some studies purporting to show health effects are inconclusive because they were relatively small and/or involved animals instead of humans. The following is a summary of some of the current research.
Curcumin has been found to react in test tubes with chemicals that contain oxygen and nitrogen.[4, 5] However, researchers are still uncertain whether this effect takes place the same way in living organisms, in part because of curcumin’s relatively low bioavailability (see below). However, some studies have found that it does have direct antioxidant effects in the intestines and can also cause various antioxidant enzymes such as glutamate-cysteine ligase to be expressed in the body, which promote critical chemical reactions.[6, 7, 8] Other studies indicate that curcumin has antioxidant effects in rats. And in a study specifically targeted at healthy people — as opposed to those with preexisting health conditions, which served as the subjects for some other curcumin studies on humans — researchers found that curcumin raised the ability of compounds in saliva to scavenge free radicals, and also raised the levels of the plasma antioxidant enzyme catalase.
Curcumin also has been found to have properties that reduce inflammation by inhibiting various enzymes and molecular pathways involved in the body’s inflammatory response. For example, in one study researchers found that a particular formulation of curcumin called Meriva, in combination with other treatments, might be an effective way to manage or even treat osteoarthritis in humans because of curcumin’s anti-inflammatory properties.[11, 16] Other studies found that curcumin had a therapeutic effect in mice with ulcerative colitis and arthritis.[13, 14, 15] Researchers have found that curcumin can help reduce inflammation following surgery and a traumatic brain injury. Because of its ability to reduce inflammation, curcumin has been found to have positive effects in patients with a host of other inflammatory diseases such as uveitis, ulcerative proctitis, Crohn’s disease, tropical pancreatitis, peptic and gastric ulcers, and lupus.
Cucumin administered orally has been found to help prevent oral, stomach, colon, and liver cancer that was chemically induced in mice.[17, 18, 19, 20, 21, 22, 23, 24] Although so far there is little clinical evidence that curcumin prevents cancer in humans, one study found that it has “enormous” potential to suppress tumor growth and the spread of cancer to other parts of the body. In addition, it has been found to interact with the same molecular targets that cancer drugs target. This means that curcumin has the potential to make chemotherapy and other cancer drugs more effective, although more studies are needed to confirm this effect.[27, 28]
Type 2 Diabetes
Some studies indicate that curcumin could help prevent and treat type 2 diabetes because of its ability to fight inflammation and lower blood sugar. For example, one nine-month study found that curcumin reduced the number of prediabetic subjects who ultimately developed diabetes. Another found that it reduced inflammation and signs of oxidative stress in people with diabetes, although it did not lower blood glucose levels. Additional research determined that curcumin improved insulin sensitivity.
Curcumin has been found to decrease concentrations of amyloid proteins in the the brains of animals, which could help slow the progression of Alzheimer’s disease. However, studies still need to be conducted to see if this effect holds for humans, and it should be noted that the percentage decrease in amyloid proteins was not large. Additional studies have produced similar results, but they also were conducted in animals or on cells in test tubes, and frequently used concentrations of curcumin that would be impractical for humans to consume.[34, 35, 36] In addition, most phase III clinical trials conducted to see whether curcumin can treat Alzheimer’s have not been successful. As a result, the effectiveness of curcumin as a treatment for the disease remains an open question.
An analysis of six randomized controlled trials found that people suffering from clinical depression who took curcumin supplements saw their symptoms decrease. The greatest effects were found after people took curcumin for at least four weeks. Additional studies have found that curcumin either had the same positive effects on symptoms as depression medications or enhanced the effects of those medications.[40, 41] The science is mixed, however, because another study found no effect from curcumin on symptoms of depression in subjects who were already taking medication for it. Thus, as with Alzheimer’s, more research is needed to determine whether curcumin is an effective treatment of depression.
Irritable Bowel Syndrome/Inflammatory Bowel Disease
Curcumin, when taken in combination with fennel essential oil, also has been found to reduce abdominal pain and other symptoms of IBS in both humans and rats.[54, 55] In addition, curcumin has been shown to relieve the symptoms of IBD due to its anti-inflammatory effects.[56, 57, 58]
Curcumin has shown some promise as a pain reliever. For example, One of the primary positive effects of curcumin on many inflammatory conditions is to relieve the pain associated with them.[60, 64] Another small study found that a particular formulation of curcumin called Meriva has the potential to relieve pain associated with high-impact sports, and it was found to relieve neuropathic pain in rats.[61, 62, 63] Finally, it has been shown to control postoperative pain and pain from burns.[65, 66]
Additional research indicates that curcumin might help people with reproductive problems caused by stress, such as male infertility. Preliminary research also indicates that it has the potential to help treat autoimmune disorders, although additional studies are needed to see whether this is true. And curcumin also might help improve HDL cholesterol and metabolism of lipids.
Supplementing with Curcumin
Turmeric only contains about 2-9 percent curcimunoids, of which curcumin is the most prevalent (the other curcimunoids are demethoxycurcumin and bisdemethoxycurcumin). On top of this, curcumin has low bioavailability because it is both poorly absorbed and quickly metabolised. However, it has been shown to be safe in high doses up to 12 grams per day.[43, 44] Even a diet containing a large amount of tumeric will only provide around 60-100 mg of curcumin per day. By contrast, in most studies showing therapeutic effects of curcumin for various conditions, the subjects consumed at least 500 mg per day. As a result, food alone is unlikely to provide enough curcumin to provide measurable health effects, and thus supplementation is needed.
Several formulations of curcumin supplements have been developed in an attempt to improve the bioavailability of curcumin. For example, a formulation called Theracurmin that includes nanoparticles of curcumin was found to increase blood concentrations of the compound. Another formulation that combined curcumin with a hydrophilic carrier, derivatives of cellulose, and antioxidants also significantly increased bioavailability compared to a standard curcumin supplement. Eating black pepper along with curcumin has been shown to increase bioavailability as well. As a result, one company (the Sabinsa Corporation) has developed a curcumin supplement that contains Bioperine, a type of black pepper extract. And, as with most nutrients that dissolve in fat, consuming fat with curcumin also will help the body use curcumin more effectively.
When choosing a curcuramin supplement, always select a high-quality brand in order to avoid supplements contaminated by impurities or toxins. Curcuramin supplemnents sold in stores usually also contain emethoxycurcumin and bisdemethoxycurcumin. Many of the labels claim to contain 95 percent curcuminoids, although this claim (as will most claims about supplements) is not regulated by the U.S. Food and Drug Administration.
Proper Dosage and Contraindications
Curcumin may increase the effects of blood-thinning medications like warfarin (Coumadin), clopidogrel (Plavix), and aspirin, which could raise the risk of excessive bleeding. It also might keep stomach acid-reducing drugs like cimetidine (Tagamet), famotidine (Pepcid), and ranitidine (Zantac), from working properly; and increase the effects of diabetes drugs, which could result in excessively low blood sugar. Finally, because of curcumin’s anti-inflammatory effects, it could have negative interactions with with non-steroidal anti-inflammatory drugs. Anyone taking any of these medications should consult a doctor before consuming curcumin.