Firstly People use Acetyl-l-carnitine as an energy booster, antioxidant, and to support mood and cognition. Secondly, Is the evidence there to support these uses? Thirdly, lets read on to discover more about the health effects and side effects of carnitine.
Generally Carnitine is an amino acid found in nearly every cell of the body. It is a generic name for a variety of compounds such as L-carnitine, acetyl-L-carnitine, and propionyl-L-carnitine.
In the same vein You’ll get carnitine from meat, fish, poultry, and milk. People with genetic disorders, chronic diseases, and those on a vegetarian diet can often benefit from supplemental carnitine. Similarly the same is true for underweight and premature babies. Other conditions that cause carnitine deficiency include angina (chest pain) and intermittent claudication (cramping leg pain from blocked arteries) .
- Effective for L-carnitine deficiency
- Additionally it Supports mitochondrial health and energy function
- Allegedly supports liver and brain health
- Finally it may improve PCOS in women and semen quality and fertility in men
Health Benefits Of Acetyl-l-Carnitine
Acetyl-l-carnitine Deficiency (Genetic)
Generally Oral and intravenous L-carnitine is effective for the treatment of primary and secondary L-carnitine deficiency due to inborn errors of metabolism (genetic).
Likely Effective for:
L-Carnitine Deficiency in Kidney Disease
Likewise Dialysis reduces carnitine levels in people with end-stage kidney disease.
Acetyl-l-carnitine Is For Possibly Effective for:
Chest Pain from Heart Disease (Angina)
Evidence suggests that taking carnitine by mouth or intravenously may improve exercise tolerance in people with chronic stable angina. Similarly as an add-on to conventional therapy, l-carnitine may also reduce the frequency of chest pain (angina) in people with angina (microvascular type).
In the same vein scientists think carnitine and its derivatives may protect heart function by increasing glucose metabolism, increasing blood flow, correcting abnormal heart rhythms, and reducing oxidative stress. In conclusion these mechanisms have yet to be confirmed in humans.
Acetyl-l-Carnitine On Heart Failure
Taking L-carnitine by mouth or intravenously (by IV) seems to improve symptoms and increase exercise capacity in people with heart failure. One study suggests that a combination of l-carnitine with ubiquinol, a form of CoQ10, may also improve symptoms of heart failure (the combination product is called Carni Q-Gel, by Tishcon Corporation) .
In a 3-year-long study on patients with heart failure, L-carnitine appeared to increase survival rates compared to the placebo.
Scientists are investigating the effects of a combination of taurine and L-carnitine on heart cells.
Acetyl-l-Carnitine On Heart Inflammation (Myocarditis)
Carnitine (D-L-carnitine) by mouth seems to reduce death rates from myocarditis associated with diphtheria, according to clinical trials.
Infertility in Men
Despite some mixed findings, most clinical studies suggest that L-carnitine increases sperm count and sperm motility in men with infertility.
Some researchers have suggested that the amount of carnitine in semen is directly related to sperm count and mobility. Carnitine seems to provide more energy for sperm cells and it may reduce cell death in the testes, according to preliminary findings.
A study of 100 infertile men revealed that the intake of carnitine supplements increased sperm motility.
Infertile men with varicose veins in the scrotum (varicocele) took carnitine for 6 months (250 mg, 4x a day). Results showed increased sperm count, mobility, and concentration .
Scientists are also exploring the antioxidant effects of carnitine on sperm in cells and in animals.
Acetyl-l-Carnitine On PCOS
Clomiphene is the typical treatment for infertility in women with PCOS. However, some women do not respond to this medication alone. Clinical research suggests that adding L-carnitine from day 3 of the cycle until the day of pregnancy testing to a clomiphene treatment cycles increases ovulation and pregnancy rates compared with placebo in these women.
Acetyl-l-Carnitine On Valproic Acid Side Effects
Valproic acid is an anticonvulsant drug that can reduce the body’s carnitine levels, potentially resulting in high ammonia levels, and brain or liver damage. L-carnitine supplementation in such individuals may prevent or reduce high ammonia levels (hyperammonemia) and the severity of liver and brain damage, according to some clinical trials.
Insufficient Evidence for:
Acetyl-l-Carnitine On Weight Loss
L-carnitine is often marketed as a weight loss aid and performance enhancer, but there is insufficient evidence to back up these purported benefits.
Acetyl-l-Carnitine On Fatigue From Disease and Aging
Fatigue is common in cancer patients after treatments from chemotherapy, radiation therapy, and poor nutrition. Some scientists believe that low carnitine levels can contribute to this fatigue.
Nonetheless, there is not enough evidence to rate the effectiveness of L-carnitine on fatigue from disease and aging.
In Dialysis Patients
Patients with kidney disease undergoing dialysis often have anemia with deformed red blood cells. The deformity prevents the blood cells from carrying enough oxygen to the body’s tissues, causing muscle weakness and fatigue.
A study following dialysis patients found that carnitine supplements reduced red blood cell deformity and increased overall red blood cell count in 3 months.
Another study on dialysis patients found that carnitine injections helped sustain higher levels of oxygen use (improved endurance), such as during exercise and also reduced overall fatigue .
Acetyl-l-Carnitine On Mood
Evidence is lacking to determine the effects of carnitine on mood.
Initial studies suggested that acetyl-L-carnitine has some antidepressant potential in elderly patients with age-associated depression .
A study found that supplementing the diets of fibromyalgia patients with acetyl-L-carnitine improved depressive symptoms and reduced muscle pain .
More human studies are needed.
Scientists are also investigating the effects of acetyl-L-carnitine on mice with depression.
Acetyl-l-Carnitine On Cognition
It’s uncertain how L-carnitine affects cognition since clinical trials are limited.
Some scientists proposed that carnitine levels gradually decline as Alzheimer’s progresses, suggesting that patients with Alzheimer’s could potentially benefit from acetyl-L-carnitine treatment.
In one small study, acetyl-L-carnitine improved memory in older people and in Alzheimer patients. The authors suggested it might slow the progression of the disease, but proper trials would need to determine its mechanism and effectiveness .
Theoretically, consuming carnitine helps the body produce acetylcholine. According to some hypotheses, this neurotransmitter declines as memory loss advances .
Thus, carnitine might hypothetically increase energy production in brain cells that are starting to “slow down” and trigger memory loss. However, this is just a scientific hypothesis that has not been verified in clinical trials.
Acetyl-l-Carnitine On Insulin Resistance
Insulin resistance has been linked with obesity and increased levels of fat in lean tissue.
Acetyl-l-carnitine For Sleep Disorders
One hypothesis says that sleep-disordered breathing is associated with heart damage and altered heart carnitine metabolism. Although carnitine levels are low in heart tissue in those with chronic heart failure, carnitine blood levels may be increased because of “leakage” from damaged heart cells and altered carnitine metabolism .
Thus, some scientists think that carnitine supplementation can help patients suffering from obstructive sleep apnea, a condition where breathing repeatedly stops and starts during sleep. Carnitine helped improve airways for breathing and improved overall sleep quality in patients in one small study .
Acetyl-l-Carnitine On Alertness in Narcolepsy
Acylcarnitine levels are abnormally low in narcolepsy patients. L-carnitine supplements may improve daytime alertness in these patients. L-carnitine treatment increased acylcarnitine and reduced blood lipids. Large-scale trials are required.
Acetyl-l-Carnitine On HIV
HIV patients may develop complications such as muscle, fat, and nerve degeneration.
Lacking Evidence (Animal and Cellular Studies)
No clinical evidence supports the use of Acetyl-l-carnitine for any of the conditions listed in this section.
Below is a summary of the existing animal and cell-based research, which should guide further investigational efforts. However, the studies listed below should not be interpreted as supportive of any health benefit.Acetyl-l-Carnitine On Kidney Function
In a rat model of chronic kidney disease, the administration of carnitine improved kidney function. Carnitine lowered the levels of creatinine and BUN in the blood, reduced kidney tissue damage and abnormal kidney enlargement.
Acetyl-l-carnitine For Bone Health
In a mouse model of osteoporosis, L-carnitine and isovaleryl-L-carnitine stimulated bone formation, improving bone turnover, bone density, bone size, and bone structure.
In the same footing another study found that dietary L-carnitine might improve the bone mineral content and bone mineral density in a female mouse model of postmenopausal bone loss. Results indicated slowed bone loss and improved bone structure.
Some scientists hypothesize that carnitine might promote bone mineralization, in part by inhibiting thyroid hormone action.
The effects of Acetyl-l-carnitine on bone health in humans are unknown.
In mouse studies of drug-induced seizure, pre-treating the mice with L-carnitine suppressed seizures dose-dependently.
A rat model of hyperthyroidism induced by L-thyroxine injections suggested that L-carnitine might have dose-dependent protective effects against liver damage .And finally L-carnitine suppresses the onset of neuromuscular degeneration and increases the lifespan of mice with familial amyotrophic lateral sclerosis (ALS).