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Who couldn’t use more energy? Taking carnitine can help. The nutrient enables our heart and other muscles to make energy, eliminate toxic byproducts, and continue to function well as we live longer.
Our bodies make carnitine from the amino acids lysine and methionine, found in proteins, but we may not produce enough when faced with physical challenges, such as exercise. In particular, anything that stresses the heart, including diabetes, any form of heart disease or precursors to these, increase carnitine demands. And, our natural ability to produce carnitine decreases as we get older.
How Carnitine Works
Each of our cells contains mitochondria, tiny components that generate energy for the cell. They’re like microscopic furnaces that use fatty acids—broken down fats—as fuel. Carnitine acts as a cargo train, transporting the fatty acids to the mitochondria and, once the fuel is burned, taking away the trash—byproducts that would be toxic if left in the cell. Without sufficient carnitine, mitochondria can’t function optimally and energy suffers.
Mitochondria also play a key role in aging because they contain their own DNA, separate from the overall cell. According to studies published in the Journal of the American Medical Association and other scientific publications, mitochondrial DNA influences cell regeneration and death, and if that DNA is damaged, cells don’t function as they should—they may die prematurely or mutate, and the aging process accelerates. Keeping mitochondria healthy is considered one of the key strategies for staying in good shape during a long life, and carnitine is a necessary ingredient.
Many studies have shown that carnitine helps the heart work more efficiently. For example, research presented at a conference sponsored by the National Institutes of Health in Bethesda, MD, included these findings:
- The heart is dependent on carnitine because fatty acids are the major source of energy for the heart muscle
- Studies of more than 2,500 patients who suffered a heart attack found that carnitine significantly reduced deaths, chest pain and shortness of breath, improved recovery of the heart, and lowered the odds of patients developing heart failure.
- Research at 49 centers in 8 European countries found that carnitine improved the ability to walk and do physical exercise in patients with chronic heart failure.
These are some other research highlights:
A study published in the journal Metabolism: Clinical and Experimental concluded that carnitine helps middle-aged people recover better from exercise, with less muscle soreness. Other research has found similar benefits among younger people.
See Also The Benefits of Carnitine Supplementation
A study of pregnant women, published in the Journal for Obstetrics and Gynecology, found that 2 grams daily of carnitine reduced the incidence of gestational diabetes. Levels of carnitine typically drop during pregnancy and may contribute to diabetes risk.
A review of research, published in Alternative Medicine Review, found that a specific form of carnitine, acetyl-l-carnitine, improved mental function among people with Alzheimer’s disease; reduced depression; helped to relieve neuropathy (disorders in nerve endings) due to diabetes, HIV drug therapy or chemotherapy; helped the brain recover from oxygen deprivation (due to a stroke, for example); and, in combination with L-carnitine, increased sperm mobility, improving male fertility.
Carnitine is an ingredient in some energy drinks and many supplement formulas, and is available as an individual supplement. It isn’t a stimulant and doesn’t cause jitters or other caffeine-like side effects.
The nutrient is also found in food, chiefly red meats, but their carnitine content is not sufficient to have the therapeutic effects produced by supplements in studies. For example, a 3-ounce serving of beef contains about 80 mg of carnitine, but in people who are not perfectly healthy, studies have most often found beneficial amounts range from 1 to 3 grams daily. To obtain just 1 gram, you would need to eat approximately 2.3 lb. of beef! If you are healthy, take 500 mg once or twice daily.
If you have diabetes, prediabetes or heart disease, take up to 3 gm daily in divided doses. Start with a lower dose and increase gradually. Carnitine is absorbed more efficiently on an empty stomach, but if you experience discomfort, take it with food.
Natrol L-Carnitine provides 500 mg of free-form L-carnitine per capsule, shown to help the body produce energy from fat and enhance workout performance. No yeast, wheat, corn, added sugar, or preservatives.
The Vitamin Shoppe CarniPure L-Carnitine Liquid Raspberry. Enjoy 1 tasty tablespoon (providing 1,100 mg L-carnitine) with morning and evening meals or before high intensity workouts. Great mixed into juice or water, too.
Jarrow Formulas L-Carnitine. Vegetarian- and vegan-friendly capsules deliver 500 mg L-carnitine. Free of gluten, soybeans, dairy, egg, fish/shellfish, and peanuts/tree nuts.