Alpha-Lipoic Acid (ALA)

Medically Reviewed by Jabeen Begum, MD on June 27, 2024
Written by Joseph Saling
6 min read

Alpha-lipoic acid (ALA) is an antioxidant your body makes. You also get it from foods such as broccoli, carrots, potatoes, and red meat. 

ALA is produced in small amounts in your heart, kidneys, liver, and muscles. It's found in every cell in your body, where its most important job is to help turn food into energy. Because it's an antioxidant, it also protects your cells against damage.

You might also hear alpha-lipoic acid called lipoic acid. It's not the same as alpha-linolenic acid, a heart-healthy omega-3 fatty acid found in nuts and seeds.

As long as you're healthy, your body can produce all the ALA it needs. But ALA supplements are widely available, and alpha-lipoic acid is included in some multivitamin and anti-aging formulas. ALA has been marketed as being helpful for everything from diabetes and HIV to weight loss.

There's some scientific evidence for a few of these potential benefits, particularly for blood sugar control and easing nerve pain caused by diabetes. But others have little, if any, scientific backing. And the FDA hasn't approved alpha-lipoic acid to treat any condition. We need more research into the effects of ALA supplements.

Antioxidants are compounds that attack unstable molecules called free radicals, which are created when your body turns food into energy. Having too many free radicals and too few antioxidants in your body causes chemical reactions that damage cells, organs, and tissues. This is called oxidative stress.

Its antioxidant benefits are why alpha-lipoic acid is thought to help with conditions that involve oxidative stress, such as diabetic nerve pain (neuropathy).

Some other antioxidants are water-soluble, such as vitamin C. That means they're effective only in fluid, such as that found in and around cells. Others, such as vitamin E, are fat-soluble and work only in fatty tissues. But ALA is water- and fat-soluble, so it can work anywhere in your body.

Also, antioxidants get used up when they fight off free radicals. But ALA can help reactivate them.

While research results have been mixed, there's some evidence that ALA has benefits for people with type 2 diabetes.

Several smaller studies have suggested that, in people with type 2, alpha-lipoic acid supplements may enhance the body's ability to use its own insulin to lower blood sugar. But a review study found it was no more effective than a placebo (fake treatment) at reducing either blood sugar, cholesterol, or blood fats (triglycerides).

Another review study looked at ALA's effects on people with several metabolic diseases, including type 2 diabetes. It found that ALA supplements lowered blood sugar as well as insulin resistance and hemoglobin A1C, an average of blood sugar levels over 2-3 months.

Alpha-lipoic acid and neuropathy

ALA may help reduce the symptoms of peripheral neuropathy , nerve damage that can be caused by diabetes. In Europe, ALA has been used for years to provide relief from the pain, burning, tingling, and numbing caused by diabetic neuropathy. In particular, one large study strongly suggested that large doses of ALA given by injection were effective at relieving symptoms.

But the evidence for ALA taken by mouth is not as strong. We need more studies into how effective oral ALA supplements are for diabetic neuropathy.

Several studies have looked at whether ALA might help with weight loss. Some researchers think ALA has potential weight-loss benefits because it suppresses an enzyme called AMP-activated protein kinase (AMPK), which plays a role in appetite.

Early research in animals found that it promoted fat loss. But so far, research has found its effects on weight in humans to be modest. 

For example, one review analysis of 12 studies found that research participants who took an ALA supplement lost about 1.5 pounds during the study periods (which averaged 14 weeks) than those who got placebos. Another review that involved 47 studies found an average weight loss of 5 pounds. In both reviews, the participants' waist measurements didn't change much.

 

ALA is an ingredient in many skin-care products. Its antioxidant qualities are thought to help protect and repair skin. But we don't have a lot of good-quality research into how effective it is.

One small study found that a cream containing 5% ALA helped reduce fine lines on the face due to sun damage when used for 12 weeks. Early studies in animals showed that alpha-lipoic acid might also help heal skin damage due to cigarette smoke and promote wound healing. We need further research to see if these effects might apply to people.

ALA has been suggested as a potential aid in stopping or slowing the damage done by a variety of other health conditions, including:

  • HIV
  • Liver disease
  • Cataracts
  • Cancer
  • Glaucoma
  • Altitude sickness
  • High cholesterol
  • Eye damage from diabetes
  • Multiple sclerosis
  • Stroke
  • Dementia
  • Erectile dysfunction (erection problems)
  • Ear infections

But much of the research into these alpha-lipoic acid uses is in its early stages. There's not enough evidence to say whether ALA is effective for these purposes.

Side effects from ALA supplements are generally mild and include rashes, headache, heartburn, nausea, and vomiting. But experts don't know much about the possible effects of long-term use of these supplements.

How much alpha-lipoic acid should you take a day?

There are no official alpha-lipoic acid dosage recommendations. Diabetic nerve pain has been treated with 600-1,800 milligrams a day. Daily doses from 200 to 2,400 milligrams are considered safe, but there's no benefit to extra-high doses.

Precautions

Don't take ALA without your doctor's OK if you take insulin or other medications to lower blood sugar. It might boost the effect of these drugs and lead to hypoglycemia (low blood sugar). Your doctor may recommend that you increase monitoring of your blood sugar levels if you take ALA. They may also want to adjust your blood sugar medication.

ALA may also decrease levels of thyroid hormone in the body, so check with your doctor before taking it if you take thyroid medications. They may need to monitor your hormone levels.

It can also interfere with some treatments for cancer and medications that slow down blood clotting.

Because no studies have been done on the effect of using ALA supplements during pregnancy, don't use it if you're pregnant. We also don't know whether it's safe for children, so don't take it while nursing, and don't give it to kids.

Avoid doses that exceed 121 milligrams per kilogram (or 2.2 pounds) of your body weight. Studies have found that such a high dose could affect liver function.

Foods with alpha-lipoic acid

Food sources of ALA include:

  • Beets
  • Broccoli
  • Brussels sprouts
  • Peas
  • Potatoes
  • Red meat, especially organ meats like liver
  • Rice bran
  • Spinach
  • Tomatoes
  • Yams
  • Yeast, such as brewer's yeast

But food doesn't provide as much ALA as you usually get in supplements.

ALA supplements

You can buy supplements as capsules or tablets, usually containing 100 to 600 milligrams of ALA. Your doctor can also give it to you as an injection.

Studies show that your body absorbs about 30%-40% of the oral dose of an ALA supplement. You may absorb it better if you take it on an empty stomach , at least 30 minutes before a meal.

Alpha-lipoic acid is an antioxidant produced naturally in your body and found in some foods. Some research has shown it may have promise in treating conditions such as diabetic neuropathy. But we need more large, good-quality studies to be sure. ALA supplements aren't right for everyone, so talk to your doctor before you take them.

How long does it take for alpha-lipoic acid to work?

People who get IV injections of ALA for diabetic nerve pain see improvement in about 3 weeks. Taking ALA by mouth doesn't seem to have the same effect. 

What should you avoid when taking alpha-lipoic acid?

Don't nurse a child when taking ALA, and don't take it while pregnant. Check with your doctor before using alpha-lipoic acid supplements if you take:

  • Medications or supplements that lower blood sugar
  • Thyroid medications
  • Cancer treatments
  • Drugs that hinder blood clotting

What food has the most alpha-lipoic acid?

Foods rich in ALA include organ meats such as liver and kidneys as well as green veggies such as spinach and broccoli. 

Does alpha-lipoic acid burn belly fat?

While some studies found ALA supplements helped overweight people lose small amounts of weight, it didn't affect the size of their waists.