Alpha-Lipoic Acid
Alpha-lipoic acid (ALA) is an endogenous antioxidant cofactor sold as a glucose-disposal agent. It is claimed to improve insulin sensitivity and shuttle nutrients into muscle, and has genuine clinical use for diabetic neuropathy. Evidence for body-composition benefit is modest and largely anecdotal.
01 Overview
ALA is a disulphide compound involved in mitochondrial energy metabolism that also regenerates other antioxidants. The R-enantiomer is the biologically active form; many supplements are racemic. It has real clinical evidence for symptomatic relief of diabetic peripheral neuropathy, especially intravenously.
In bodybuilding it is dosed before carbohydrate meals as a glucose-disposal agent, on the premise that it enhances insulin-stimulated glucose uptake. Human data for meaningful fat loss or partitioning are weak, and effects are best described as modest.
02 Mechanism
Acts as a mitochondrial cofactor and antioxidant; is thought to activate AMPK and enhance GLUT4 translocation and insulin-stimulated glucose uptake, and to regenerate glutathione and other antioxidants.
03 Dosing
| Tier | Dose | Route | Notes |
|---|---|---|---|
| Supplement | 300–600 mg/day | Oral | Often taken with carbohydrate meals; R-ALA more potent per mg |
| High (neuropathy studies) | 600–1800 mg/day | Oral | Doses used in neuropathy trials |
04 Effects
| Effect | Magnitude | Evidence | |
|---|---|---|---|
| Improved insulin-stimulated glucose uptakeMay enhance glucose disposal, supported by some human infusion studies. | Modest | Clinical | |
| Relief of diabetic neuropathy symptomsIV and oral ALA reduce neuropathic symptoms in trials. | Clinical |
05 Side effects
| Effect | Severity | Frequency | Evidence | Countermeasures |
|---|---|---|---|---|
| Gastrointestinal upsetNausea, heartburn or abdominal discomfort at higher doses. | Mild | Common | Observational | |
| Hypoglycaemia risk with diabetic drugsMay lower blood glucose additively with insulin or oral agents. | Moderate | Uncommon | Observational |