When should I take it?

Often on an empty stomach, since food can reduce its absorption. If it upsets your stomach, take it with a light meal.

R-ALA is the active form and may be more potent per milligram; standard (racemic) ALA is cheaper and used in most studies. Either is reasonable.

Can it lower blood sugar too much?

It can have a mild glucose-lowering effect, so if you take diabetes medication, monitor and coordinate with your provider.

Alpha-Lipoic Acid: Benefits, Dosing & Evidence

What it is

Alpha-lipoic acid is a compound your body makes in small amounts that acts as an antioxidant and helps convert glucose into energy. It's both water- and fat-soluble, letting it work throughout the body.

How it works

Alpha-lipoic acid (ALA) is a compound your cells make in small amounts that helps convert glucose into energy and acts as a versatile antioxidant — unusual in being both water- and fat-soluble, so it works throughout the cell. It can also regenerate other antioxidants like vitamins C and E. These properties underlie its study for blood sugar and nerve comfort.

What it's been studied for

Taken to support healthy blood sugar and metabolic health; also studied for nerve comfort.

What the evidence shows

A meta-analysis found alpha-lipoic acid improved glucose control in people with metabolic conditions. It has a reasonable evidence base for blood-sugar support relative to many supplements.

Who should consider it

It's used mainly by people focused on blood-sugar and metabolic health, and it's studied for nerve discomfort (diabetic neuropathy) in clinical settings. Those interested in antioxidant support sometimes use it too. It has a reasonable evidence base for glucose relative to many supplements.

Amounts commonly studied

Studies commonly use 300-600 mg per day, often taken on an empty stomach for absorption.

How to take it

Studies commonly use 300-600 mg per day, often on an empty stomach (30-60 minutes before a meal) for better absorption. The R-form is the biologically active version; many products use a racemic mix. Split dosing is sometimes used since it clears quickly. Coordinate with your provider if you take diabetes medication, as it can lower blood sugar.

Forms & absorption

The R-form is the biologically active version; many products use a racemic mix. Take away from meals for better absorption.

Food sources

Tiny amounts occur in red meat, organ meats, spinach, broccoli, and tomatoes, but far below supplemental doses — the body makes most of what it uses.

Safety & interactions

Generally well tolerated; can cause mild digestive upset and may lower blood sugar, so coordinate with a provider if you take diabetes medication.

Myths & what it won't do

Myth: ALA is a proven fat-burner. Reality: any weight effect is minor; its better-supported roles are glucose control and antioxidant activity. Myth: all ALA is the same. Reality: the R-isomer is the active form, and products vary — though standard ALA is still used in much of the research.

Common questions

When should I take it?: Often on an empty stomach, since food can reduce its absorption. If it upsets your stomach, take it with a light meal.
R-ALA or regular?: R-ALA is the active form and may be more potent per milligram; standard (racemic) ALA is cheaper and used in most studies. Either is reasonable.
Can it lower blood sugar too much?: It can have a mild glucose-lowering effect, so if you take diabetes medication, monitor and coordinate with your provider.

The amounts listed here are what published research has used — not a prescription or a recommended dose for you. Confirm anything you plan to take with your own healthcare provider, especially if you take medications, are pregnant or nursing, or have a health condition.

Alpha-Lipoic Acid