Carnosine: benefits, dosage, contraindications
Scientific name(s)
Beta-alanyl-L-histidine
Family or group:
Amino acids
Indications
Scoring methodology
EFSA approval.
Cognitive decline ✪✪✪✪✪
Preliminary clinical research indicates that taking a combination of 250 mg carnosine and 750 mg anserine per day for 3 to 6 months may help preserve certain aspects of memory, such as delayed verbal recall, compared with placebo. However, no other changes in cognitive function were observed. A meta-analysis of three clinical trials shows that taking a combination of carnosine and anserine at 1 g per day in a 1:2 or 1:3 ratio for 12 weeks modestly improves overall cognitive function compared with placebo. Another systematic review examined the effects of carnosine/anserine supplementation on cognitive decline. The authors concluded that carnosine/anserine, administered for 12 weeks at a dose of 500 mg to 1 g per day, improved overall cognitive function in the studies reviewed. These findings suggest preliminary evidence of the clinical efficacy of carnosine against cognitive decline in older adults and in patients with mild cognitive impairment. The authors emphasize the need for larger and longer-term studies to confirm these results.
Posologie
Oral
250 - 1500 mg
β-Alanine ingestion increases muscle carnosine content and combat-specific performance in soldiers
Biochemical Mechanisms of Beneficial Effects of Beta-Alanine Supplements on Cognition
Effect of Anserine/Carnosine Supplementation on Verbal Episodic Memory in Elderly People
The Therapeutic Potential of Carnosine/Anserine Supplementation against Cognitive Decline: A Systematic Review with Meta-Analysis
The Potential of Carnosine in Brain-Related Disorders: A Comprehensive Review of Current Evidence
A preliminary, randomized, double-blind, placebo-controlled trial of L-carnosine to improve cognition in schizophrenia
Sports performance ✪✪✪✪✪
A small clinical study conducted in healthy men suffering from muscle fatigue showed that taking a combination of 2 grams of carnosine and 2 grams of beta-alanine as a single dose 4 hours before the test increased maximal voluntary muscle contractions during knee extensions by 15% and jump height by 6% compared with placebo. However, muscle pain increased 24 hours after taking carnosine and beta-alanine. In another small clinical trial in healthy men, taking a single dose of 2.5 grams of carnosine plus 2.5 grams of beta-alanine did not affect most measures of sports performance, including perceived exertion, work rate, maximal workload, and oxygen uptake, compared with placebo. However, a small benefit was observed for ventilatory threshold during a test. High-intensity exercise provokes a significant oxidative stress response, leading to inflammation and muscle damage, and attenuating oxidative stress may be beneficial for the recovery process and subsequent exercise performance. However, the investigation of carnosine as an antioxidant in vivo has been limited to animal models. Therefore, the effectiveness of carnosine as an antioxidant in humans remains to be explored.
Posologie
Orally
2 g
Effects of Acute Carnosine and β-Alanine on Isometric Force and Jumping Performance
Acute preexercise supplementation of combined carnosine and anserine enhances initial maximal power of Wingate tests in humans
Effects of β-Alanine Supplementation on Carnosine Elevation and Physiological Performance
Effects of oral administration of orodispersible levo-carnosine on quality of life and exercise performance in patients with chronic heart failure
Acute carnosine and β-alanine supplementation increase the compensated part of the ventilation versus work rate relationship during a ramp incremental cycle test in physically active men
Muscle carnosine metabolism and beta-alanine supplementation in relation to exercise and training
Muscle pain ✪✪✪✪✪
Several studies have examined the effect of carnosine on muscles. They conclude that carnosine supplementation significantly increases carnosine levels in muscles, which has a positive effect on athletic performance, particularly in combat sports. The beneficial effects include improved muscular endurance and reduced fatigue. nnIt should be noted that carnosine helps maintain acid-base balance in muscles during intense exercise. nn
Posologie
Orally
2 g
Effects of Beta-Alanine on Muscle Carnosine and Exercise Performance: A Review of the Current Literature
β-Alanine Supplementation in Combat Sports: Evaluation of Sports Performance, Perception, and Anthropometric Parameters and Biochemical Markers-A Systematic Review of Clinical Trials
Muscle carnosine metabolism and beta-alanine supplementation in relation to exercise and training
Dry skin ✪✪✪✪✪
A preliminary clinical study conducted in diabetic adults suffering from severe dryness of the skin of the foot shows that the use of a cream containing 5% urea, 0.5% arginine and 0.01% carnosine twice daily for 8 months improves skin hydration and reduces xerosis compared with a control emollient cream. The carnosine cream reduced xerosis by 91% compared with baseline, versus a 23% reduction with the control cream.nnXerosis is a condition characterized by extreme dryness of the skin. It is more common in people with diabetes due to dehydration and reduced blood circulation.nn
Posologie
Topical
250 µg
Synergies
Night Cream Containing Melatonin, Carnosine and Helichrysum italicum Extract Helps Reduce Skin Reactivity and Signs of Photodamage: Ex Vivo and Clinical Studies
Glaucoma ✪✪✪✪✪
A preliminary clinical study conducted in patients with primary open-angle glaucoma shows that taking a specific supplement in the form of two tablets twice daily for one year, in addition to standard topical treatment, results in a reduction in intraocular pressure compared with standard treatment alone.nnOne tablet contains 50 mg of carnosine, 150 mg of coleus extract (standardized to 10% forskolin), 100 mg of homotaurine, 1.1 mg of vitamin B1, 1.4 mg of vitamin B2, 1.4 mg of vitamin B6, 0.2 mg of folic acid, and 150 mg of magnesium.nn
Posologie
Oral
100 mg
Synergies
Biomarkers and special features of oxidative stress in the anterior segment of the eye linked to lens cataract and the trabecular meshwork injury in primary open-angle glaucoma: challenges of dual combination therapy with N-acetylcarnosine lubricant eye drops and oral formulation of nonhydrolyzed carnosine
Depression ✪✪✪✪✪
Preliminary clinical research conducted in patients with major depressive disorder shows that taking 400 mg of carnosine twice daily, together with citalopram treatment titrated up to a dose of 40 mg per day for 6 weeks, improves depression symptoms measured on the Hamilton Depression Rating Scale (HAM-D), compared with placebo and citalopram.
Posologie
Orally
800 mg
Type 2 Diabetes ✪✪✪✪✪
A meta-analysis of two small clinical trials shows that taking carnosine at a dose of 1 g per day for 12 weeks reduces glycated hemoglobin (HbA1c) by about 0.9% in diabetic patients or those with glucose intolerance, compared with placebo. Fasting blood glucose also appears to be reduced based on these studies. Other preliminary clinical research conducted in obese adults with diabetes shows that taking an individualized combined supplement containing 6 mg/kg of carnosine, 7 mg/kg of alpha-lipoic acid, and 1 mg/kg of thiamine three times a day for 8 weeks reduces HbA1c and fasting blood glucose compared with baseline. The validity of this result is limited by the absence of a comparison group.
Posologie
Orally
1 - 2 g
Synergies
L-carnosine supplementation attenuated fasting glucose, triglycerides, advanced glycation end products, and tumor necrosis factor-α levels in patients with type 2 diabetes: a double-blind placebo-controlled randomized clinical trial
Effects of carnosine supplementation on glucose metabolism: Pilot clinical trial
Diabetic nephropathy ✪✪✪✪✪
A small clinical trial conducted in patients with type 2 diabetes and diabetic nephropathy shows that taking carnosine at a dose of 1 g twice daily for 12 weeks does not improve blood urea nitrogen or serum creatinine levels, nor the glomerular filtration rate, compared with placebo. However, a slight improvement is observed in urinary levels of transforming growth factor (TGF)-beta, a marker of kidney damage in these patients.
Posologie
Oral
2 g
Metabolic syndrome ✪✪✪✪✪
Some preliminary clinical research shows that daily intake for 4 months of a specific product containing 456 mg of cinnamon extract, 2.5 mg of chromium and 400 mg of carnosine reduces fasting blood glucose and lean mass compared with placebo. However, there was no change in glycated hemoglobin, insulin sensitivity, or body weight. Other observational research conducted in adults at risk of metabolic syndrome showed that taking carcinine, a metabolite of carnosine, at a dose of 60 mg per day for 8 weeks was associated with improvements in blood glucose, glycated hemoglobin, serum insulin, insulin resistance and total cholesterol compared with a control group. More studies are needed to confirm the efficacy of carnosine for metabolic syndrome.
Posologie
Oral
400 mg
Synergies
The role of Carcinine treatment on glico-lipidic imbalance of patients with altered blood glucose pattern
Healthy aging ✪✪✪✪✪
Carnosine has been studied for its anti-aging effects, particularly in combating glycation. This process, often accelerated in people with diabetes, involves a chemical reaction between sugars and proteins, forming structures called advanced glycation end products (AGEs). These AGEs contribute to cellular aging by causing tissue damage, making vascular walls more rigid and promoting the onset of chronic diseases such as heart disease and cataracts. In vitro and in vivo studies show that carnosine can limit glycation by preventing the formation of these unwanted bonds, thereby protecting cells from induced damage and the body from the effects of aging.
Posologie
Orally
500 mg
Novel Facial Cream Containing Carnosine Inhibits Formation of Advanced Glycation End-Products in Human Skin
Skin beautification with oral non-hydrolized versions of carnosine and carcinine: Effective therapeutic management and cosmetic skincare solutions against oxidative glycation and free-radical production as a causal mechanism of diabetic complications and skin aging
Properties
Anti-aging
Carnosine (beta-alanyl-L-histidine) is a dipeptide, a non-enzymatic free radical scavenger and a natural antioxidant. It is widely distributed in tissues and occurs at particularly high concentrations in muscle and the brain. In the brain, the cells containing the most carnosine are astrocytes and oligodendrocytes. Carnosine has been found to be an antioxidant and a free radical scavenger and to play a role in the rejuvenation of senescent cells, notably fibroblasts. Clinically, carnosine can delay the deterioration of vision during aging while exerting a remarkable effect on the prevention and treatment of senile cataract. However, recent findings have shown that increased release of carnosine by astrocytes is under the control of zinc. These results are highly important, given the significance of zinc for neuro-immune interactions and, at the same time, for carnosine's own protective role. Zinc plays a specific role in brain functions, such as synaptic transmission, for example. Recent discoveries have suggested that carnosine is capable of inhibiting the aggregation of amyloid peptide and that the toxic effects of amyloid peptide can be prevented or reduced by carnosine. Therefore, carnosine, via the bioavailability of the zinc ion, can be used as a potential anti-aging drug. Carnosine can also increase the lifespan of CD4-positive T cell clones and mitigate the deleterious effects of high concentrations of TNF-alpha in injured rats, thereby protecting immune cells through its antioxidant activity. Good bioavailability of intracellular zinc ions, which is necessary for maintaining the immune system in aging individuals, may be largely due to metallothionein homeostasis and the positive antioxidant effect of carnosine, which act through the zinc pool. On the other hand, fascinating results show the positive effects of the zinc complex of L-carnosine (generic name: Polaprezinc), which is capable of increasing spermatogenesis in an experimental model of accelerated aging in mice and which also reduces inflammation during gastric ulcer. This confirms the relevance of carnosine and zinc (as a complex) as new potential anti-aging factors related to neuroendocrine-immune interactions.
Usages associés
Antioxidant
The antioxidant properties of carnosine have been demonstrated by its ability to trap reactive oxygen species and to react directly with superoxide anions and peroxyl radicals in vitro. Carnosine's ability to act as an antioxidant is mainly due to its histidine component, whereas β-alanine has been found ineffective as an antioxidant itself.
Usages associés
Cognitive function
Carnosine has several potentially beneficial roles for the brain. It can act as a neurotransmitter, strengthen the immune system, modulate nitric oxide metabolism, chelate heavy metals, improve cellular metabolism, and act as an anti-glycation and anti-aging agent. It could also modulate the glutamatergic system by regulating the glutamate transporter and by reducing glutamate concentrations in the central nervous system. Carnosine may play a role in protection against cognitive decline. Preclinical studies have shown reductions in oxidative stress and microglial activation in the brain. It should be noted that chronic microglial activation can cause damage to neurons by releasing potentially cytotoxic molecules such as pro-inflammatory cytokines. This chronic inflammatory response can contribute to neurodegenerative diseases and other brain disorders.
Usages associés
Neurological
Carnosine acts as a powerful antioxidant, protecting the brain against oxidative stress and damage caused by free radicals. It plays a crucial role in preventing neurodegeneration, notably by inhibiting the aggregation of abnormal proteins, such as beta-amyloid (Aβ) involved in Alzheimer’s disease, and by reducing levels of nitric oxide (NO) and superoxide (O2-) in microglial cells. Several mechanisms of action have been highlighted, such as the inhibition of the formation of advanced glycation end products (AGEs) and advanced lipoxidation end products (ALEs), which are implicated in various neurodegenerative diseases, as well as its ability to bind metal ions of zinc (Zn2+) and copper (Cu2+), which helps regulate zinc and copper homeostasis in the synaptic cleft and protect the brain. Indeed, it has been shown that copper and zinc ions play a key role in the aggregation of Aβ peptides and in neuronal toxicity in patients with Alzheimer’s disease.
Usages associés
Toxic effects of beta-amyloid(25-35) on immortalized rat brain endothelial cell: protection by carnosine, homocarnosine and beta-alanine
Endogenous mechanisms of neuroprotection: role of zinc, copper, and carnosine
Musculoskeletal effects
Carnosine is part of a family of histidine-containing dipeptides found in the skeletal muscle of all vertebrates, but its content is particularly high in mammals that rely on anaerobic metabolism to fuel their activity. Anaerobic metabolism is a biological process that enables energy production in the absence of oxygen. It occurs in cells during intense physical exercise. Instead of using oxygen to break down glucose, anaerobic metabolism converts glucose into lactic acid. Carnosine, anserine and balenine are all widely distributed in mammalian tissues, but carnosine appears to be the main histidine dipeptide in humans. There is a strong positive relationship between carnosine content and muscle buffering capacity across species, with a significantly higher concentration of carnosine in fast-twitch muscle fibers than in slow-twitch fibers. The primary physiological role of carnosine in skeletal muscle appears to be its buffering function, helping to maintain acid–base balance during intense exercise. Its ability to bind muscle hydrogen ions during intense exercise moderates the drop in intracellular pH, which allows exercise to continue for a longer duration. High intramuscular carnosine concentrations would delay the onset of muscle fatigue during intense exercise lasting 1 to 5 minutes. Recent studies have suggested that intramuscular carnosine may also act as an exchanger of calcium and hydrogen ions at the level of muscle fibers; for example, when it binds more hydrogen ions, this can lead to the release of calcium ions within the muscle fibers. This release of calcium promotes better muscle contraction and thereby increases the force produced by the muscles.
Usages associés
Hypoglycemic
Carnosine may benefit diabetic subjects because it reduces protein glycosylation, that is, the biochemical process where sugar molecules bind to proteins. This process can alter the function and stability of proteins and produce what are called advanced glycation end products (AGEs). AGEs are known to be responsible for diabetes complications such as cataracts, neuropathy, and kidney failure. Carnosine may help improve insulin resistance and prevent diabetes. In one study, taking carnosine reduced levels of an adipokine (a type of protein that plays an important role in metabolism, notably in the regulation of appetite, inflammation, insulin, and glucose metabolism) called resistin, which is involved in regulating glucose metabolism. Carnosine also affects iron metabolism, which could improve insulin resistance and reduce the risk of type 2 diabetes. Carnosine could influence iron metabolism, an important factor in the control of insulin resistance and the development of type 2 diabetes. One study showed that carnosine reduces levels of the transferrin receptor in plasma in obese patients, suggesting it may affect how iron is used in the body. This could, in turn, improve insulin resistance. You may wonder how iron can influence diabetes? In fact, yes — iron can play a role in type 2 diabetes; its excess can lead to insulin resistance and metabolic syndrome, partly due to the oxidative stress it induces. Additionally, high concentrations of iron biomarkers, such as ferritin and the soluble transferrin receptor, have been observed in obesity and type 2 diabetes.
Usages associés
Histidine and carnosine delay diabetic deterioration in mice and protect human low-density lipoprotein against oxidation and glycation
Carnosine Supplementation Improves Serum Resistin Concentrations in Overweight or Obese Otherwise Healthy Adults: A Pilot Randomized Trial
Vision
In animal models, carnosine has antioxidant effects on the crystalline lens and protects against cataract. This effect results from antiglycation and antioxidant activities.
Usages associés
Antioxidant activity of L-carnosine, a natural histidine-containing dipeptide, in the crystalline lens
Carnosine and Beta-Alanine Supplementation in Human Medicine: Narrative Review and Critical Assessment
Use of carnosine as a natural anti-senescence drug for humans
[Preventive effect of carnosine on cataract development]
Safe dosage
Adults aged 16 and over: 500 mg - 2000 mg
Carnosine has most often been taken alone at doses of 500 mg to 2000 mg per day for 4 to 12 weeks. It has also been used at doses of 250 mg per day in combination with anserine at 750 mg per day for 3 to 6 months. Anserine is a dipeptide composed of β-alanine and 3-methylhistidine. It is a methylated derivative of carnosine, which makes it more stable in serum and more resistant to degradation than carnosine.
Interactions
Médicaments
Antidiabetic: minor interaction
Some preliminary clinical research suggests that carnosine may reduce fasting blood glucose.
Precautions
Pregnant women: avoid
Insufficient information.
Breastfeeding: avoid
Insufficient information.
Surgery: avoid
Theoretically, carnosine could interfere with blood glucose control during and after surgical procedures. It is recommended to stop carnosine at least 2 weeks before a surgical procedure.
