Browse our library for articles on vitamins, supplements, healthy living topics, and more.
Carnitine is a protein-like substance that the body synthesizes from two amino acids, methionine and lysine. Carnitine plays a central role in transporting fatty acids to muscle cells, including heart cells, which convert fatty acids to energy. Carnitine also helps maintain healthy levels of cholesterol and triglycerides in the bloodstream and helps prevent unhealthy accumulations of fatty acids in the heart, liver, and muscles. The body stores carnitine in the heart and skeletal muscles.
Scientists have conducted a significant amount of clinical research on carnitine’s role in human health and have found that carnitine supplementation can help prevent and treat cardiovascular disease, chronic fatigue syndrome, Alzheimer’s disease, and male infertility.
The body can manufacture all the carnitine it needs if sufficient amounts of the amino acids lysine and methionine—the building blocks of carnitine—are available. These amino acids can be found abundantly in animal products, including beef, pork, chicken, organ meats, and dairy products. Additionally, carnitine supplements are available in health food stores.
Carnitine deficiency is rare, but some studies have found low levels in several groups of patients. According to Michael Murray, N.D., author of The Encyclopedia of Nutritional Supplements, people with the following conditions may be at risk for carnitine deficiency:
• Dietary deficiency of lysine and methionine, the precursors to carnitine
• Dietary deficiency of any cofactors required for carnitine synthesis, including ascorbic acid, iron, niacin, and pyroxidine
• Genetic defect that prevents carnitine synthesis
• Poor intestinal absorption of carnitine
• Kidney or liver dysfunction that interferes carnitine synthesis
• Defective transport of carnitine
• High metabolic losses of carnitine
• Increased requirements for carnitine due to disease, drugs, metabolic stress, or a high-fat diet
Symptoms of carnitine deficiency include muscle weakness, fatigue, chest pain, and confusion. If you are at risk for carnitine deficiency and experience any of these symptoms, please consult with your physician.
BENEFITS OF CARNITINE SUPPLEMENTS
CARDIO VASCULAR DISEASE
According to Stephen L. DeFelice, MD, author of The Carnitine Defense, “There is compelling scientific evidence that supplemental carnitine offers great cardiovascular benefits. It can not only help prevent heart disease but also helps treat several heart problems, including myocardial ischemia, a lack of oxygen to the heart, and cardiomyopathy, a weak heart, in certain patients. . . . I believe that for a significant number of people, taking carnitine supplements can be a life-saving habit.”
Clinical trials and animal studies have confirmed the benefits that carnitine offers for cardiovascular disorders, including myocardial infarction, congestive heart failure, ischemia, arrythmias, and peripheral vascular disease.
In a study published in the American Heart Journal in 2000, eighty participants were divided into two groups and received two grams of L-carnitine or a placebo every day for three years. At the end of the study, sixty-three participants were alive. Analysis of the data revealed that the survival rate was significantly higher in the group that received the carnitine supplement.
Another study, which was published in the Postgraduate Medical Journal in 1996, looked at 101 subjects who were randomly assigned to receive two grams of L-carnitine per day or placebo for twenty-eight days. Researchers found that the subjects taking the carnitine supplement had a large reduction in the severity of cardiac damage caused by heart attacks. Additionally, the carnitine group experienced significantly fewer cases of angina pectoris and heart failure. The researchers concluded, “It is possible that L-carnitine supplementation in patients with suspected acute myocardial infarction may be protective against cardiac necrosis and complications during the first 28 days.”
CHRONIC FATIGUE SYNDROME
Although research is mixed, some studies have found a deficiency of L-carnitine in people with chronic fatigue syndrome. Additionally, researchers have found that carnitine supplementation can help relieve symptoms of chronic fatigue syndrome.
In a study published in the journal Neuropsychobiology in 1997, researchers gave three grams of L-carnitine per day to thirty people with chronic fatigue syndrome. After eight weeks of treatment with L-carnitine, participants demonstrated significant clinical improvements in twelve of the eighteen parameters measured in the study.
In a more recent study of ninety people with chronic fatigue syndrome that was published in Psychosomatic Medicine in 2004, supplementation with acetyl-L-carnitine and propionyl-L-carnitine resulted in significant improvement in both mental fatigue and general fatigue scores among the study’s participants. While more research needs to be done on the role of L-carnitine in chronic fatigue syndrome, early results are promising.
Evidence is mounting in favor of carnitine’s effectiveness in slowing the rate of neurological deterioration associated with Alzheimer’s disease. In a double-blind, placebo-controlled study published in the Archives of Neurology in 1992, researchers randomly assigned thirty participants with mild to moderate Alzheimer’s disease to receive either three grams of acetyl-L-carnitine per day or a placebo. After six months the acetyl-L-carnitine group showed significantly less deterioration in timed cancellation tasks and digital-recall tests. The researchers concluded that, “A subgroup of AD patients aged sixty-five or younger may benefit from treatment with acetyl-L-carnitine.”
In another study, this one published in the journal Neurology in 1991, scientists divided 130 people with Alzheimer’s disease into two groups, one that received two grams of acetyl-L-carnitine per day and one that received a placebo. Researchers utilized fourteen diagnostic instruments to assess functional and cognitive impairment. While impairment in both groups worsened after one year, the group that received acetyl-L-carnitine showed a slower rate of deterioration in thirteen of the fourteen diagnostic measurements.
Concentrations of L-carnitine can be found in the epididymis and sperm cells of the male reproductive system. Scientists have found that L-carnitine plays a key role in sperm motility and respiration, making adequate carnitine levels essential for male fertility. Clinical research demonstrates that L-carnitine supplementation can benefit men with fertility problems. In a study published in Fertility and Sterility in 2005, researchers gave thirty participants with male infertility two grams of L-carnitine per day for three months. Sperm health was measured at baseline and after carnitine treatment. Results revealed that participants who received L-carnitine and had normal mitochondrial function showed a significant increase in sperm motility above baseline levels.
In another study, which was published in the Annals of the New York Academy of Sciences in 2004, researchers wanted to know if carnitine supplementation would reduce infertility among sixty men with low sperm counts, atypical sperm, or reduced sperm motility. Participants were given two grams of L-carnitine and one gram of acetyl-L-carnitine or a placebo daily for two months. Men receiving the carnitine supplements demonstrated significantly improved sperm count, motility, and form over those receiving placebo.
While athletes and sports enthusiasts have used carnitine supplements to enhance performance, little evidence exists to support the claim that carnitine supplements can enhance energy, stamina, or overall athletic performance. Some studies have found, however, that carnitine supplements may help reduce muscle soreness in some athletes.
While some people claim that carnitine supplements promote weight loss, little, if any, credible scientific evidence supports this claim.
FORMS AND USUAL DOSAGES
L-carnitine and acetyl-L-carnitine supplements are available as tablets, capsules, and chewable wafers. Dosages of acetyl-L-carnitine used in studies on cardiovascular disease and Alzheimer’s range from 1.5 to three grams per day, with a usual dose of two grams per day. Carnitine supplements may cause nausea and vomiting, especially when taken on an empty stomach, so it’s best to take them with meals. If you have heart disease, diabetes, kidney disease, liver disease, or any other serious medical condition, be sure to consult with your physician before taking a carnitine supplement.
Atar D., Spiess M., et al. “Carnitine—from cellular mechanisms to potential clinical applications in heart disease.” European Journal of Clinical Investigation. 1997 Dec;27(12):973–76.
Benvenga S., Ruggeri R.M. “Usefulness of L-carnitine, a naturally occurring peripheral antagonist of thyroid hormone action, in iatrogenic hyperthyroidism: a randomized, double-blind, placebo-controlled clinical trial.” Journal of Clinical Endocrinology and Metabolism. 2001 Aug;86(8):3579–94.
Cruciani R.A., Dvorkin E. et al. “L-carnitine supplementation for the treatment of fatigue and depressed mood in cancer patients with carnitine deficiency: a preliminary analysis.” Annals of the New York Academy of Sciences. 2004 Nov;1033:168–76.
Garolla A., Maiorino M., et al. “Oral carnitine supplementation increases sperm motility in asthenozoospermic men with normal sperm phospholipid hydroperoxide glutathione peroxidase levels.” Fertility and Sterility. 2005 Feb;83(2):355–61.
Hiatt, W.R., Regensteiner, J.G. “Propionyl-L-carnitine improves exercise performance and functional status in patients with claudication.” American Journal of Medicine. 2001 Jun 1;110(8):616–22.
Lenzi A., Sgrò P., et al. “A placebo-controlled double-blind randomized trial of the use of combined l-carnitine and l-acetyl-carnitine treatment in men with asthenozoospermia.” Fertility and Sterility. 2005 Sep; 84(3):662–71.
Murray, Michael. Encyclopedia of Nutritional Supplements. New York: Three Rivers Press, 1996.
Ng C.M., Blackman M.R., et al. “The role of carnitine in the male reproductive system.” Annals of the New York Academy of Sciences. 2004 Nov;1033:177–88.
Pauly D.F., Pepine C.J. “The role of carnitine in myocardial dysfunction.” American Journal of Kidney Disorders. 2003 Apr;41(4 Suppl 4):S35–43.
Plioplys A.V., Plioplys S. “Amantadine and L-carnitine treatment of chronic fatigue syndrome.” Neuropsychobiology. 1997;35(1):16–23.
Rizos I., Hiatt W.R. “Three-year survival of patients with heart failure caused by dilated cardiomyopathy and L-carnitine administration.” American Heart Journal. 2000 Feb;139(2 Pt 3):S120–23.
Sano M., Bell K., et al. “Double-blind parallel design pilot study of acetyl levocarnitine in patients with Alzheimer’s disease.” Archives of Neurology. 1992 Nov;49(11):1137–41.
Singh R.B., Niaz M.A., et al. “A randomised, double-blind, placebo-controlled trial of L-carnitine in suspected acute myocardial infarction.” Postgraduate Medical Journal. 1996 Jan;72(843):45–50.
Spagnoli A., Lucca U., et al. “Long-term acetyl-L-carnitine treatment in Alzheimer’s disease.” Neurology. 1991 Nov;41(11):1726–32.
What do Worcestershire sauce, mustard and Middle Eastern cuisine have in common? All feature turmeric, the yellow, peppery spice commonly associated with Indian curries. And new research suggests that turmeric may be good for more than just spicing up your diet.
Turmeric (Curcuma longa) is a tropical perennial plant that belongs to the ginger (Zingiberaceae) family. Turmeric is native to Asia and thrives in clay-like soil in warm, wet climates. Turmeric was first cultivated over 5,000 years ago in what is present-day Pakistan, but it wasn’t introduced to the Western world until the thirteenth century. Today, 90 percent of all turmeric is produced in India—not surprising, since India is the world’s largest exporter and consumer of the spice.
Commercial turmeric is produced from the plant’s rhizome, a horizontal underground stem with knobby fingerlike branches. The rhizome is cleaned, boiled, dried and ground into powder. Turmeric powder has been used for thousands of years as a seasoning, as a preservative, as a dye and as a medicine.
AN ANCIENT CURE FOR MODERN TIMES
Turmeric is an important herb in Ayurveda, an ancient Indian healing tradition that is one of the oldest medical systems in the world. According to Ayurvedic tradition, turmeric has many uses: relieving pain, regulating menstruation, aiding digestion, supporting liver health and more.
Turmeric also plays a role in traditional Chinese medicine (TCM), where it is used to regulate the qi, or life force. Chinese healers use turmeric to provide topical pain relief and to support blood flow, bile production and digestive health. TCM practitioners also consider turmeric a powerful anti-inflammatory.
Curcumin, the main active constituent of turmeric, is a powerful antioxidant, and many of turmeric’s health benefits are linked to antioxidant activity; in fact, researchers from the Indian Agricultural Research Institute evaluated the antioxidant activity of 36 Asian vegetables and found turmeric to be the most potent. But modern research has also found turmeric to have anti-inflammatory, antispasmodic and antibacterial properties. Turmeric may even heal wounds and fight tumors.
ACAI AND YOUR HEALTH
Acai’s abundant nutrients have some real and important effects on your health, including the following:
TURMERIC AND CANCER
In 1992, researchers from the Cancer Research Institute in Bombay, India, studied the effects of curcumin on cancer in mice. Their findings, published in the Journal of the American College of Nutrition, showed that curcumin could inhibit cancer initiation, promotion and progression.
In the same year, researchers from India’s National Institute of Nutrition examined the effects of curcumin on mutagens in smokers. (Mutagens, molecules that alter genetic information, are frequently carcinogenic.) After giving 16 chronic smokers 1.5 grams of turmeric daily for 30 days, the researchers reported a reduction in the smokers’ urinary mutagen excretions.
Research on turmeric and cancer is not limited to India. In 2005, researchers at the United Kingdom’s University of Leicester investigated the potential use of curcumin for humans with colon cancer. For seven days, patients with colorectal cancer received a capsule containing curcumin (some received 450 milligrams, some 1.8 grams and others 3.6 grams). The researchers reported that a 3.6-gram dose of curcumin reduced levels of M(1)G (a biomarker for cancer) in colorectal tissue.
TURMERIC AND DIGESTIVE HEALTH
In 2001, faculty from the department of pharmacology at Mahidol University in Bangkok, Thailand, used turmeric to treat 25 patients with peptic ulcers. The researchers gave each patient five 600-milligram doses of turmeric per day: before each meal, at 4 PM, and at bedtime. After four weeks, ulcers had healed in 12 patients (48 percent); after eight weeks, ulcers had healed in 18 patients (72 percent); and after 12 weeks, ulcers had healed in 19 patients (76 percent)—a significant improvement over the typical 40 percent rate of spontaneous healing for untreated ulcers.
In 2003, after finding that curcumin reduced symptoms and inflammatory markers in mice with inflamed colons, researchers at the Indian Institute of Chemical Biology suggested curcumin as a treatment for irritable bowel disease.
In 2004, the Journal of Complementary and Alternative Medicine published the results of a randomized pilot study of the effects of turmeric extract on irritable bowel syndrome (IBS) symptoms. In this study, researchers gave 207 subjects with IBS one or two tablets of turmeric daily for eight weeks. After treatment, symptoms improved in roughly two-thirds of the subjects.
TURMERIC, BLOOD SUGAR AND DIABETES
Diabetes is becoming an epidemic in the United States—the National Institute of Diabetes and Digestive and Kidney Diseases reports that 23.6 Americans (nearly eight percent of the population) had diabetes in 2007. Animal studies suggest that turmeric may be helpful for diabetes and related complications, although clinical studies have yet to confirm the findings.
The September 2008 issue of Molecular Nutrition & Food Research reported a study on the effects of curcumin on blood glucose and insulin in mice. Korean researchers fed diabetic and non-diabetic mice curcumin for six weeks (mice in the control group received no curcumin). Curcumin significantly lowered blood glucose levels in the diabetic mice, but not in the non-diabetic mice. These findings suggest that curcumin may play a role in glucose control for type 2 diabetes.
In 2007, researchers at Wayne State University in Michigan found that curcumin may help prevent diabetic retinopathy, a common complication in diabetics and a leading cause of blindness in the United States. In a placebo-controlled study, the researchers fed diabetic rats curcumin for six weeks and then examined the rat’s retinas for signs of inflammation and oxidative stress. They found that curcumin protected the rats’ eyes by preventing diabetes from reducing the antioxidant capacity of the retinas.
Curcumin may also protect against other complications associated with diabetes. In 1995, Indian researchers reported that curcumin improved metabolic health in diabetic rats. In 1998, the same researchers found that eight weeks of curcumin supplementation improved symptoms of diabetes-related kidney damage in rats.
TURMERIC AND CARDIOVASCULAR HEALTH
In 1992, researchers at the Amala Cancer Research Centre in India conducted a small clinical trial to evaluate the effects of curcumin on cholesterol levels and lipid peroxides (oxidized fatty acids). Ten volunteers received 500 milligrams of curcumin per day for seven days. At the end of the study, the volunteers showed decreased levels of lipid peroxides and cholesterol, and increased levels of HDL (“good”) cholesterol. Based on these findings, the researchers recommended further research on the potential use of curcumin to prevent arterial disease.
In 2005, Hossam Arafa, a researcher at Al-Azhar University in Cairo, Egypt, studied the effects of curcumin on blood lipid levels in rats. Arafa fed rats a high-cholesterol diet for seven days, raising their blood lipid and LDL (“bad”) cholesterol levels while lowering their HDL cholesterol levels. Arafa then introduced curcumin to the rats’ diets, which reversed many of the damaging effects of the high-cholesterol diet, lowering blood lipid and LDL levels while raising HDL levels. Arafa concluded that curcumin has obvious cholesterol-lowering effects unrelated to its antioxidant activity.
TURMERIC AND THE MIND
Alzheimer’s disease is a degenerative brain disease that affects memory and other cognitive functions. Though it is associated with age, Alzheimer’s disease is not a normal part of aging. Researchers have identified several risk factors for Alzheimer’s disease, including genetics, environmental toxins, oxidation and inflammation.
Because of its antioxidant and anti-inflammatory properties, some researchers hypothesize that turmeric may reduce the risk of Alzheimer’s disease. This hypothesis is supported by the low rates of Alzheimer’s disease in India, where turmeric is a common spice and Alzheimer’s disease affects as little as one percent of the elderly populations in some villages.
Research on animals explains how turmeric protects against Alzheimer’s disease. A team of researchers at the University of California, Los Angeles, conducted one such study in 2001, testing the effects of curcumin on inflammation, oxidation and plaque buildup in mice with symptoms of Alzheimer’s. Curcumin decreased all three, leading the researchers to conclude that curcumin shows promise as a preventive treatment for Alzheimer’s disease.
TURMERIC AND ARTHRITIS
Arthritis, or joint inflammation, causes pain and limits movement. There are more then 100 types of arthritis, all of which involve degeneration of the cartilage that normally protects joints. Often, arthritis is caused by injury, infection or wear and tear. Sometimes, as in cases of rheumatoid arthritis, it is caused by autoimmune responses in which the body attacks its own cells.
Because of its anti-inflammatory properties, some researchers have considered turmeric as a potential treatment for arthritis. In 2006, researchers at the Center for Phytomedicine Research at the University of Arizona used turmeric to treat rats with symptoms of rheumatoid arthritis. Some of the rats received treatment before the onset of symptoms, and some of the rats after. The researchers found that an extract containing primarily curcuminoids (including curcumin) reduced joint swelling, but only when treatment was given before the onset of symptoms. The researchers concluded that curcuminoids are responsible for turmeric’s antiarthritic action.
WHERE TO GET YOUR TURMERIC
Turmeric is available in capsules, liquid extracts and tinctures—even in teas, thanks to the spice’s growing popularity. Many turmeric supplements contain bromelain, an enzyme derived from pineapple that improves the absorption and anti-inflammatory action of curcumin. For those using supplements, alternative health guru Dr. Andrew Weil recommends 400 to 600 milligrams of turmeric extract three times a day. Or, you can skip the pills and bottles and simply enjoy more curries and Indian food. Whichever route you take, your body is sure to thank you.
THE BOTTOME LINE
Turmeric is a delicious and widely available spice with numerous health benefits. Whether you take it as a supplement or use it spice up your diet, turmeric provides a healthy dose of antioxidants that may help prevent or provide relief for chronic conditions such as Alzheimer’s disease, arthritis, cardiovascular disease and more. There’s a reason cultures around the world have used turmeric for thousands of years—so go ahead and have another dish of curry.
TUMERIC THE FAST FACTS
Possible Uses: Reduce inflammation and cholesterol; relieve symptoms of inflammatory bowel disease (IBD), rheumatoid arthritis and cystic fibrosis; prevent cancer and Alzheimer’s disease; support liver and cardiovascular function.
Sources: Turmeric is a common spice and is featured prominently in curries and many Middle Eastern cuisines. Turmeric supplements are available as capsules, liquids, tinctures and teas.
Instructions: Take a 400 to 600 milligram dose of turmeric extract three times a day. Look for supplements with bromelain, which may increase absorption and improve curcumin’s anti-inflammatory action.
Contraindications: Turmeric is generally considered safe and nontoxic. Though rare, some people may experience allergic reactions to turmeric, including skin irritation and anaphylaxis.
A SPICE BY ANY OTHER NAME
The authors of Turmeric: The Genus Curcuma report that turmeric has 55 names in Sanskrit, each describing the spice’s medicinal and religious uses. A few of these names, along with their meanings, are listed below:
• Ranjani: that which gives color
• Mangal prada: auspicious, lucky
• Krimighni: killing worms (refers to turmeric’s antimicrobial action)
• Hemaragi: being the color of gold
• Varna-datri: that which gives color (refers to turmeric’s ability to enhance the complexion)
• Pavitra: holy
• Hridayavilasani: delighting the heart
(Adapted from Barbara Wexler’s Turmeric manuscript)
Arafa, H.M. 2005. “Curcumin attenuates diet-induced hypercholesterolemia in rats.” Medical Science Monitor 11(7): BR228–34.
Bapu, P.S. and K. Srinivasan. 1995. “Influence of dietary curcumin and cholesterol on the progression of experimentally induced diabetes in albino rat.” Molecular & Cellular Biochemistry 152(1): 13–21.
Bundy, R. et al. 2004. “Turmeric may improve irritable bowel syndrome symptomology in otherwise healthy adults: a pilot study.” Journal of Alternative & Complementary Medicine 10(6): 1015–18.
Funk, J.L. et al. 2006. “Turmeric extracts containing curcuminoids prevent experimental rheumatoid arthritis.” Journal of Natural Products 69(3): 351–55.
Garcea, G. et al. “Consumption of the putative chemopreventive agent curcumin by cancer patients: assessment of curcumin levels in the colorectum and their pharmacodynamic consequences.” Cancer Epidemiology, Biomarkers & Prevention 14(1) 120–25.
Kaur, C. and H.C. Kapoor. 2002. “Anti-oxidant activity and total phenolic content of some Asian vegetables.” International Journal of Food Science & Technology 37(2): 153–61.
Kowluru, R.A. and M. Kanwar, 2007. “Effects of curcumin on retinal oxidative stress and inflammation in diabetes.” Nutrition & Metabolism 4(Apr 16): 8.
Lim, G.P. et al. 2001. “The curry spice curcumin reduces oxidative damage and amyloid pathology in an Alzheimer transgenic mouse.” Journal of Neuroscience 21(21): 8370–77.
Nagabhushan, M. and S.V. Bhide. 1992. “Curcumin as an inhibitor of cancer.” Journal of the American College of Nutrition 11(2): 192–98.
Polasa, K. et al. 1992. “Effect of turmeric on urinary mutagens in smokers.” Mutagenesis 7(2): 107–09.
Prucksunand, C. et al. 2001. “Phase II clinical trial on effect of the long turmeric (Curcuma longa Linn) on healing of peptic ulcer. Southeast Asian Journal of Tropical Medicine & Public Health 32(1): 208–15.
Salh, B. et al. 2003. “Curcumin attenuates DNB-induced murine colitis.” American Journal of Physiology. Gastrointestinal & Liver Physiology 285(1): G235–43.
Seo, K.I. et al. 2008. “Effect of curcumin supplementation on blood glucose, plasma insulin, and glucose homeostasis related enzyme activities in diabetic db/db mice.” Molecular Nutrition & Food Research 52(9): 995–1004.
Soni, K.B. and R. Kuttan. 1992. “Effect of oral curcumin administration on serum peroxides and cholesterol levels in human volunteers.” Indian Journal of Physiology and Pharmacology 36(4): 273–75.
Suresh Babu, P. and K. Srinivasan. 1998. “Amelioration of renal lesions associated with diabetes by dietary curcumin in streptozotocin diabetic rats.” Molecular & Cellular Biochemistry 181(1–2): 87–96.
Ukil, A. et al. 2003. “Curcumin, the major component of food flavour turmeric, reduces mucosal injury in trinitrobenzene sulphonic acid-induced colitis.” British Journal of Pharmacology 139(2): 209–18.
Weil, A. “3 reasons to eat turmeric.” http://www.drweil.com/drw/u/ART03001/Three-Reasons-to-Eat-Turmeric.html.
Wexler, B. 2008. Need title for turmeric booklet. Salt Lake City, UT: Woodland.