Alpha-lipoic acid: benefits, dosage, contraindications

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Alpha-lipoic acid (AAL) is a powerful antioxidant whose chemical structure is similar to a vitamin. It is synthesized endogenously, mainly in the liver and other tissues, but can also be obtained through the diet. Yeast, liver, red meats, spinach, and broccoli are good sources of alpha-lipoic acid. Alpha-lipoic acid is an enzyme cofactor in metabolic and energy pathways. It is involved at the mitochondrial level, which, combined with its antioxidant properties, gives it anti-aging properties. It is used mainly in the management of diabetes and neuropathies, but also in the modulation of immunity and inflammation.

Other name(s) 

Lipoic acid

Scientific name(s)

alpha-lipoic acid

Family or group: 

Pseudovitamins


Indications

Scoring methodology

EFSA approval.

Several randomized, double-blind, controlled clinical trials (> 2), including a significant number of patients (>100), with consistently positive conclusions for the indication.
Several randomized, double-blind, controlled clinical trials (> 2), including a significant number of patients (>100), with positive conclusions for the indication.
One or more randomized studies, or several cohorts or epidemiological studies, with positive conclusions for the indication.
Clinical studies exist but are uncontrolled, with conclusions that may be positive or conflicting.
No clinical studies to date that can demonstrate the indication.


Oxidative stress
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Exogenous alpha-lipoic acid and its metabolite dihydrolipoic acid (DHLA) have antioxidant activity and can scavenge free radicals both intracellularly and extracellularly. In addition, alpha-lipoic acid is both water- and fat-soluble and can regenerate endogenous antioxidants such as vitamin E, vitamin C, and glutathione, thereby preventing tissue and neuronal damage caused by oxidative stress such as cerebral ischemia, brain injury caused by excitotoxic amino acids, mitochondrial dysfunction, muscle ischemia associated with peripheral arterial disease, diabetes, and diabetic neuropathy. The antioxidant effects of alpha-lipoic acid may also be beneficial in liver diseases associated with oxidative stress.

Posologie

posologieOrally

posologie300 - 600 mg


Wrinkles
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Applying a night cream containing 5% alpha-lipoic acid would reduce the appearance of fine lines and damage caused by sun exposure. Another study highlights improvements in skin elasticity and thickness indicators after oral intake of ALA together with vitamins, minerals, and a maritime pine extract.

Posologie

posologieTopical, oral

populationAdults


Type 2 diabetes
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A meta-analysis of 16 small clinical studies in patients with type 2 diabetes shows that daily intake of 200 to 1,200 mg of alpha-lipoic acid for up to 52 weeks leads to a slight improvement in glycemic measures, which is not clinically significant. Compared with placebo, alpha-lipoic acid reduced fasting glucose by 6 mg/dL, glycated hemoglobin (HbA1c) by 0.17%, and triglyceride levels by 19 mg/dL.

Posologie

posologieOral

posologie200 - 1,200 mg

duration52 - weeks

populationAdults

Efficacy and safety of oral alpha-lipoic acid supplementation for type 2 diabetes management: a systematic review and dose-response meta-analysis of randomized trials
Enhancement of glucose disposal in patients with type 2 diabetes by alpha-lipoic acid.
Scientific Opinion on the substantiation of health claims related to alpha-lipoic acid and protection of body lipids from oxidative damage (ID 1434, 3134), maintenance of normal blood cholesterol concentrations (ID 3134), increased beta-oxidation of fatty acids (ID 3134), maintenance of normal blood glucose concentrations (ID 1435, 3162), and "regeneration of genes, regeneration of gene transcription and the influence on NF-kappa B activity" (ID 3133) pursuant to Article 13(1) of Regulation (EC) No 1924/2006
Oral administration of RAC-alpha-lipoic acid modulates insulin sensitivity in patients with type-2 diabetes mellitus: a placebo-controlled, pilot trial.
Glycemic and oxidative status of patients with type 2 diabetes mellitus following oral administration of alpha-lipoic acid: a randomized double-blinded placebo-controlled study.
Alpha-lipoic acid (ALA) supplementation effect on glycemic and inflammatory biomarkers: a systematic review and meta-analysis.
Effect of alpha-lipoic acid on blood glucose, insulin resistance, and glutathione peroxidase in patients with type 2 diabetes.
Improvement of insulin-stimulated glucose disposal in type 2 diabetes after repeated parenteral administration of thioctic acid.
Alpha-lipoic acid treatment decreases serum lactate and pyruvate concentrations and improves glucose effectiveness in lean and obese patients with type 2 diabetes.
The effects of lipoic acid and a-tocopherol supplementation on the lipid profile and insulin sensitivity of patients with type 2 diabetes mellitus: a randomized, double-blind, placebo-controlled trial.

Metabolic syndrome
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The increase in inflammatory markers, particularly TNF-α, may promote insulin resistance and alter cytokine expression in adipose tissues, which is considered an important link between metabolic syndrome and insulin resistance. ALA supplementation can reduce inflammatory markers by scavenging free radicals. The results of a meta-analysis indicate that ALA supplementation significantly reduced levels of C-reactive protein, interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α) (inflammatory markers) in patients diagnosed with metabolic disorders.

Posologie

posologieOral administration

posologie300 - 600 mg


Properties


Antioxidant

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The antioxidant properties of alpha-lipoic acid (AAL) lie in its ability to scavenge free radicals and to regenerate endogenous antioxidants: glutathione and vitamins C and E. AAL can protect lipids against oxidative damage and may also help maintain normal blood cholesterol levels.

Usages associés

Wrinkles, Diabetic neuropathy, Oxidative stress, Cardiovascular diseases, Dyslipidemia

Bioenergetic

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Alpha-lipoic acid plays an important role in burning fats to produce energy, and in the transport of fatty acids across the mitochondrial membranes (cellular organelle), where they are oxidized and converted into energy.

Usages associés

Obesity

Anti-inflammatory

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Alpha-lipoic acid modulates the inflammatory response and can inhibit vascular inflammation. The anti-inflammatory effect has also been correlated in several studies with a decrease in pro-inflammatory cytokines (small proteins secreted by inflammatory cells) such as TNF-alpha and IL-6.

Usages associés

Diabetic neuropathy, Metabolic syndrome, Cardiovascular diseases

Hypoglycemic

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Alpha-lipoic acid helps lower blood glucose levels and regulate insulin resistance. In addition, it has been shown to be effective in protecting against protein glycation (a natural reaction caused by excessively high concentrations of sugars in the blood, as occurs in diabetes), and helps regulate the damage caused by advanced glycation end products. These glycation-derived products are highly harmful to the body, accumulate with age, and thus contribute to the development of several diseases such as atherosclerosis, nephropathy, and diabetic retinopathy.

Usages associés

Type 2 diabetes

Anti-aging

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Alpha-lipoic acid has shown positive effects in combating certain forms of oxidation and inflammation, which among other things helps protect against age-associated neurological decline. Alpha-lipoic acid is also a powerful antioxidant and, from this perspective, is considered an anti-aging ally.

Usages associés

Wrinkles

Chelator

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Alpha-lipoic acid has been shown to chelate heavy metals. In animal research, alpha-lipoic acid has been shown to increase the hepatobiliary excretion of inorganic mercury by forming a stable complex.


Anticancer

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Alpha-lipoic acid has been shown to induce apoptosis (programmed cell death) in human colon cancer cells in vitro. Moreover, ALA has demonstrated antimutagenic activities in tumorigenic cellular models in animals and humans, including breast cancer, melanoma, ovarian epithelial cancer and colon cancer, by inhibiting inflammatory mediators, DNA fragmentation and metastasis.

Usages associés

Cancer


Safe dosage

Adults aged 18 years and older: 200 mg - 1200 mg

By oral administration, alpha-lipoic acid is very well tolerated in humans up to a dose of 1200 mg/day and with treatment durations up to 4 weeks.; It can also be applied topically for 12 weeks.


Interactions

Médicaments

Anticancer drugs: moderate interaction

The use of alpha-lipoic acid during chemotherapy is controversial. Indeed, antioxidants could reduce the activity of chemotherapy (including cyclophosphamide, chlorambucil, carmustine, busulfan and thiotepa) by generating free radicals. However, some researchers have hypothesized that antioxidants could make chemotherapy more effective by reducing oxidative stress that may interfere with the apoptosis (cell death) of cancer cells.

Antidiabetic drugs: weak interaction

Theoretically, the use of alkylating agents can cause hypoglycemic effects in a person with diabetes.

Hormones: moderate interaction

Theoretically, administering alpha-lipoic acid with thyroid hormone-based medications reduces their therapeutic effects.

Plantes ou autres actifs

Hypoglycemic: weak interaction

In theory, alpha-lipoic acid could have additive effects with plants that lower blood glucose levels. Herbs with a hypoglycemic effect include devil's claw, fenugreek, garlic, horse chestnut, Panax ginseng, psyllium, and Siberian ginseng.nn


Precautions

Type 2 diabetes: use with caution

Alpha-lipoic acid should be used with caution in people with diabetes. Indeed, it has a blood-sugar-lowering effect.

Surgical intervention: avoid

Theoretically, alpha-lipoic acid could cause excessive bleeding or interfere with blood glucose control if used perioperatively.


Contraindications

Children up to 12 years: prohibited

Alpha-lipoic acid is not recommended for children under 12 years of age.

Pregnancy: prohibited

Alpha-lipoic acid is not recommended during pregnancy.

Breastfeeding: prohibited

Due to lack of studies, avoid using lipoic acid while breastfeeding.

Vitamin B1 deficiency: prohibited

Alpha-lipoic acid should not be used in cases of thiamine deficiency (vitamin B1 deficiency in alcoholics, for example), unless this deficiency is treated.