Studies also L-carnitine and heart health its Caffeine alertness pills for ueart, brain hrart, and healht prevention. View at Publisher View at Google Scholar L-carnitine and heart health I, Chandrashekhan Y, De Giuli F, Pasini E, Mazzoletti A, Confortini R, Ferrari R. View at Publisher View at Google Scholar Xu XQ, Jing ZC, Jiang X, Zhao QH, He J, Dai LZ, Wu WH, Li Y, Yao J.

L-carnitine and heart health -

Vegans or people with certain genetic issues may be unable to produce or obtain enough. This makes L-carnitine a conditionally essential nutrient 2.

L-carnitine is the standard biologically active form of carnitine, which is found in your body, foods, and most supplements. For most people, acetyl-L-carnitine and L-carnitine seem to be the most effective for general use.

In cells, it helps transport fatty acids into the mitochondria, where they can be burned for energy. L-carnitine may help increase mitochondrial function, which plays a key role in disease and healthy aging 1 , 10 , L-carnitine is an amino acid derivative that transports fatty acids into your cells to be processed for energy.

It is made by your body and also available as a supplement. One review of 37 studies found that L-carnitine supplementation significantly reduced body weight, body mass index BMI , and fat mass. However, it had no effect on belly fat or body fat percentage Another analysis of nine studies — mostly in individuals with obesity or older adults — found that people lost an average of 2.

Furthermore, while it may aid in weight loss for some people, you may wish to consult with a dietician to develop a thorough diet and exercise regimen first. Some studies suggest that L-carnitine could help promote weight loss and fat loss.

However, more studies are needed. Some research suggests that the acetyl form, acetyl-L-carnitine ALCAR , may help prevent age-related mental decline and improve markers of learning In fact, according to one study, taking 1, milligrams mg of ALCAR daily for 28 weeks significantly improved brain function in people with dementia For instance, a review of two studies showed that taking L-carnitine for 3 days had no effect on markers of brain function — including reaction time, vigilance, immediate memory, and delayed recall — in young adults without cognitive impairment L-carnitine — specifically acetyl-L-carnitine — may have beneficial effects on brain function.

Still, more research is needed. For example, one review of 10 studies found that L-carnitine significantly reduced diastolic blood pressure, especially in people with overweight and obesity Another analysis of 17 studies showed that L-carnitine could improve heart function and decrease symptoms in people with congestive heart failure Additionally, a review showed that L-carnitine could reduce total and LDL bad cholesterol while increasing HDL good cholesterol in people at risk for heart disease The evidence is mixed when it comes to the effects of L-carnitine on sports performance, but it may offer some benefits.

This differs from supplements like caffeine or creatine , which can directly enhance sports performance 22 , A recent review of 41 studies concluded that L-carnitine supplementation could reduce fasting blood sugar and hemoglobin A1c a marker of long-term blood sugar levels while also improving insulin sensitivity in people with diabetes, overweight, or obesity According to the authors of the review, L-carnitine is believed to work by altering insulin receptors and changing the expression of specific genes that regulate sugar metabolism It may also help improve the function of beta cells, which are cells in the pancreas that are responsible for producing insulin In one review of 12 studies, acetyl-L-carnitine significantly reduced symptoms of depression compared with placebo Interestingly, several of the studies included in this review also found that acetyl-L-carnitine was as effective as antidepressant medications but caused fewer adverse effects Research suggests that L-carnitine may aid exercise performance and treat health conditions like heart disease, depression, and type 2 diabetes.

For most people, taking 2 grams g or less per day is relatively safe and free from any serious side effects Some research has also used doses of up to 4, mg per day However, there were some mild side effects, including heartburn and indigestion However, L-carnitine supplements may raise your blood levels of trimethylamine-N-oxide TMAO over time.

High levels of TMAO are linked to an increased risk of atherosclerosis — a disease that clogs your arteries Doses of 2 g or less per day seem to be well tolerated and safe for most people.

However, L-carnitine may increase levels of TMAO, which could be linked to an increased risk of plaque build-up. You can get small amounts of L-carnitine from your diet by eating meat and dairy products The best sources of L-carnitine are 35 :. As noted before, your body can also produce this substance naturally from the amino acids methionine and lysine if your stores are low.

For these reasons, L-carnitine supplements are only necessary in special cases, such as disease treatment. The main dietary sources of L-carnitine are meat and some other animal products, such as milk. A healthy individual can also produce sufficient amounts within the body.

For this reason, L-carnitine levels are often lower in vegetarians and vegans since they restrict or avoid animal products Therefore, vegetarians and vegans may want to consider L-carnitine supplements, which can help normalize carnitine levels in the blood and muscles In fact, one study found that taking 1.

On the other hand, another study showed that L-carnitine supplementation had no effect on muscle strength or markers of inflammation in older women The risk of deficiency is also higher for those with diseases like cirrhosis and kidney disease.

If you have one of these conditions, a supplement may be beneficial 40 , Specific populations may benefit from L-carnitine supplements. This includes older adults and people who rarely or never eat meat.

Although dosage varies from study to study, here is an overview of the use and dose for each form 13 , 19 , 33 :. Although the recommended dose varies, around —4, mg 0. Studies also support its use for health, brain function, and disease prevention.

Supplements may also benefit those with lower levels, such as older adults, vegans, and vegetarians. Of the different forms, acetyl-L-carnitine and L-carnitine are the most popular and seem to be the most effective. Our experts continually monitor the health and wellness space, and we update our articles when new information becomes available.

Carnitine is a substance that helps the body turn fat into energy. Your body makes it in the liver and kidneys and stores it in the skeletal muscles, heart, brain, and sperm.

Usually, your body can make all the carnitine it needs. Some people, however, may not have enough carnitine because their bodies cannot make enough or cannot transport it into tissues so it can be used.

Other conditions, such as angina or intermittent claudication, can also cause low levels of carnitine in the body, as can some medications. Carnitine has been proposed as a treatment for many conditions because it acts as an antioxidant.

Antioxidants fight harmful particles in the body known as free radicals, which damage cells and tamper with DNA. Antioxidants can neutralize free radicals and may reduce or help prevent some of the damage they cause. Carnitine may help treat are certain conditions. Serious diseases require conventional medical treatment, and you should talk to your health care provider before taking carnitine.

For other conditions, such as fatigue or improving athletic performance, carnitine seems safe but may not help much.

Reduced blood flow to the legs from atherosclerosis or hardening of the arteries, where plaque builds up in the arteries, often causes an aching or cramping pain in the legs while walking or exercising. This pain is called intermittent claudication, and the reduced blood flow to the legs is called peripheral vascular disease PVD.

Several studies show that carnitine can help reduce symptoms and improve mobility among people with intermittent claudication. Most studies have used propionyl-L-carnitine. Scientists do not know whether L-carnitine would work the same. Diabetic neuropathy happens when high blood sugar levels damage nerves in the body, especially the arms, legs, and feet, causing pain and numbness.

Preliminary studies suggest acetyl-L-carnitine may help reduce pain and increase feeling in affected nerves. It is also possible that carnitine can help nerves regenerate. More research is needed. Although L-carnitine has been marketed as a weight loss supplement, scientific evidence is lacking.

Some studies show that oral carnitine may help reduce fat mass, increase muscle mass, and reduce fatigue, which may contribute to weight loss in some people. Evidence is mixed as to whether carnitine is useful in treating Alzheimer disease. Several early studies showed that acetyl-L-carnitine, might help slow down the progression of Alzheimer disease, relieve depression related to senility and other forms of dementia, and improve memory in the elderly.

But larger and better-designed studies found it did not help at all. People should take carnitine for Alzheimer disease and other forms of dementia only under the supervision of their provider. Because the kidneys make carnitine, kidney disease could lead to low levels of carnitine in the body.

If you have kidney disease, your provider may prescribe carnitine. DO NOT take carnitine without medical supervision.

Low sperm counts have been linked to low carnitine levels in men. Several studies suggest that L-carnitine supplements may increase sperm count and motility. Preliminary studies suggest propionyl-L-carnitine may help improve male sexual function.

One study found that carnitine improved the effectiveness of sidenafil Viagra in men with diabetes who had not previously responded to Viagra.

In another study, a combination of propionyl-L-carnitine and acetyl-L-carnitine improved the effectiveness of Viagra in men who had erectile dysfunction after prostate surgery.

More studies are needed. Peyronie disease is characterized by a curvature of the penis that leads to pain during an erection.

One promising study compared acetyl-L-carnitine to the medication tamoxifen in 48 men with this condition. Acetyl-L-carnitine worked better than tamoxifen at reducing pain during sex and reducing the curve of the penis. Acetyl-L-carnitine also had fewer side effects than tamoxifen.

Some research suggests that L-carnitine may help prevent or reduce symptoms of an overactive thyroid, such as insomnia, nervousness, heart palpitations, and tremors. In fact, in one study, a small group of people with hyperthyroidism saw these symptoms improve, and their body temperature become normal, when taking carnitine.

But a larger, better-designed clinical trial is needed to see if carnitine really works. In addition, researchers think carnitine may work by blocking the action of thyroid hormone, which could be dangerous for people with low thyroid levels.

DO NOT take carnitine for hyperthyroidism without your doctor's supervision. Red meat particularly lamb and dairy products are the main food sources of carnitine. It can also be found in fish, poultry, tempeh, wheat, asparagus, avocados, and peanut butter. Avoid D-carnitine supplements.

They interfere with the natural form of L-carnitine and may produce unwanted side effects. In some cases, L-carnitine may be taken by prescription or given intravenously by a health care provider.

Pediatric DO NOT give carnitine supplements to a child without your child's health care provider's supervision. Your child's provider should first make sure that the child has a carnitine deficiency. Recommended doses of L-carnitine vary depending on the health condition being treated.

The usual dose is between 1 to 3 g per day. Because supplements may have side effects or interact with medications, you should take them only under the supervision of a knowledgeable health care provider. Side effects are generally mild.

High doses 5 or more grams per day may cause diarrhea. Other rare side effects include increased appetite, body odor, and rash. If you are being treated with any of the following medications, you should not use carnitine without first talking to your health care provider. AZT: In a laboratory study, L-carnitine supplements protected muscle tissue against toxic side effects from AZT, a medication used to treat HIV and AIDS.

More studies are needed to know whether L-carnitine would have the same effect in people. Doxorubicin: Treatment with L-carnitine may protect heart cells against the toxic side effects of doxorubicin, a chemotherapy medication used to treat cancer, without making the medication any less effective.

Always talk to your oncologist before using complementary or alternative CAM therapies with chemotherapy. Isotretinoin Accutane : Accutane, a strong medication used for severe acne, can cause liver problems, as measured by a blood test, as well as high cholesterol, and muscle pain and weakness.

These symptoms are like those seen with carnitine deficiency. Researchers in Greece showed that a large group of people who had side effects from Accutane got better when taking L-carnitine compared to those who took a placebo.

Thyroid hormone: Carnitine may stop thyroid hormone from getting into cells, and theoretically may make thyroid hormone replacement less effective. If you take thyroid replacement hormone, talk to your provider before taking carnitine. Valproic acid Depakote : The antiseizure medication valproic acid may lower blood levels of carnitine.

Taking L-carnitine supplements may prevent any deficiency and may also reduce the side effects of valproic acid. However, taking carnitine may increase the risk of seizures in people with a history of seizures. Blood Thinning Medications: Carnitine may increase the risk of bleeding in people taking blood thinning medicaitons.

Benvenga S, Ruggieri RM, Russo A, Lapa D, Campenni A, Trimarchi F. Usefulness of L-carnitine, a naturally occurring peripheral antagonist of thyroid hormone action, in iatrogenic hyperthyroidism: a randomized, double-blind placebo-controlled clinical trial.

J Clin Endocrinol Metab. Berni A, Meschini R, Filippi S, Palitti F, De Amicis A, Chessa L. L-carnitine enhances resistance to oxidative stress by reducing DNA damage in Ataxia telangiectasia cells. Mutat Res.

Herat research shows little risk of infection from prostate biopsies. L-carnutine at work is linked Matcha green tea for brain health high L-carnitine and heart health pressure. Icy fingers and toes: Poor circulation or Raynaud's phenomenon? Herat CONTENT: As a service to our readers, Harvard Health Publishing provides access to our library of archived content. Please note the date each article was posted or last reviewed. No content on this site, regardless of date, should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician. L-Carnitine Linked to Heagt Health L-carnitinf Research Suggests This L-carnitine and heart health Acid Could Help Cardiac Patients By Christin L. Found Herbal sleep aid in red meat and haert as an hearr L-carnitine and heart health supplement, L-carnitine plays L-carnitine and heart health important role in energy metabolism L-cwrnitine blood glucose regulation. In the heart, L-carnitine L-carnitine and heart health L-cafnitine important as the myocardium prefers L-carbitine oxidize long-chain fatty acids for energy. Because of its importance in metabolic pathways, L-carnitine is widely marketed as a nutritional supplement, heralded as a way to boost energy production, promote weight loss, and improve athletic performance. Most notably, studies of L-carnitine supplementation in athletes have been disappointing. According to Janet Bond Brill, PhD, RD, LDN, a heart health expert and the author of Blood Pressure Down! But recent research examining the effects of L-carnitine supplementation in cardiac patients appears promising, as studies indicate that maintaining sufficient levels of this amino acid in heart muscle appears to offer several protective benefits, prompting further consideration as to whether L-carnitine can effectively treat cardiac disease.