Alpha-lipoic acid has gained a lot of attention in recent years.
It’s an organic compound that acts as a powerful antioxidant in the body.
Your body produces alpha-lipoic acid naturally, but it’s also found in a variety of foods and as a dietary supplement.
Research suggests that it may play a role in weight loss, diabetes and other health conditions.
However, many wonder whether it’s effective.
This article reviews alpha-lipoic acid, its benefits, side effects and recommended dosage.
Alpha-lipoic acid is an organic compound found in all human cells.
It’s made inside the mitochondria — also known as the powerhouse of the cell — where it helps enzymes turn nutrients into energy ().
What’s more, it has powerful antioxidant properties.
Alpha-lipoic acid is both water- and fat-soluble, which allows it to work in every cell or tissue in the body. Meanwhile, most other antioxidants are only either water- or fat-soluble ().
For instance, vitamin C is just water-soluble, while vitamin E is just fat-soluble.
The antioxidant properties of alpha-lipoic acid have been linked to benefits like lower blood sugar levels, reduced inflammation, slowed skin aging and improved nerve function.
Humans only produce alpha-lipoic acid in small amounts. That’s why many turn to certain foods or supplements to optimize their intake.
Animal products like red meat and organ meats are great sources of alpha-lipoic acid, but plant foods like broccoli, tomatoes, spinach and Brussels sprouts also contain it.
That said, supplements can pack up to 1,000 times more alpha-lipoic acid than food sources (3).
Summary Alpha-lipoic acid is an organic compound that works as an antioxidant. It’s made in the mitochondria of cells but is also found in foods and supplements.
Research has shown that alpha-lipoic acid may affect weight loss in several ways.
Animal studies indicate that it can reduce the activity of the enzyme AMP-activated protein kinase (AMPK), located in your brain’s hypothalamus (, ).
When AMPK is more active, it may increase feelings of hunger.
On the other hand, suppressing AMPK activity may increase how many calories your body burns at rest. Thus, animals who took alpha-lipoic acid burned more calories (, ).
However, human studies show that alpha-lipoic acid has only a slight impact on weight loss.
An analysis of 12 studies discovered that people who took an alpha-lipoic acid supplement lost an average of 1.52 pounds (0.69 kg) more than those taking a placebo over an average of 14 weeks ().
In the same analysis, alpha-lipoic acid did not significantly affect waist circumference.
Another analysis of 12 studies found that people who took alpha-lipoic acid lost an average of 2.8 pounds (1.27 kg) more than those on a placebo over an average of 23 weeks ().
In short, it seems that alpha-lipoic acid has just a slight effect on weight loss in humans.
Summary Though alpha-lipoic acid has properties that may promote weight loss, its overall effect in humans seems negligible.
Diabetes affects more than 400 million adults worldwide ().
A key feature of uncontrolled diabetes is high blood sugar levels. If left untreated, this can cause health problems, such as vision loss, heart disease and kidney failure.
Alpha-lipoic acid has become popular as a potential aid for diabetes, as it’s been shown to lower blood sugar levels in both animals and humans.
In animal studies, it has effectively lowered blood sugar levels by as much as 64% (, ).
Other studies in adults with metabolic syndrome have shown that it may reduce insulin resistance and lower fasting blood glucose and HbA1c levels.
Scientists believe that alpha-lipoic acid helps lower blood sugar by promoting processes that can remove fat that has accumulated in muscle cells, which otherwise make insulin less effective ().
Moreover, alpha-lipoic acid may lower the risk of diabetes complications.
It’s proven to ease symptoms of nerve damage and lower the risk of diabetic retinopathy (eye damage) that can occur with poorly controlled diabetes (, , 16).
It’s believed that this effect is due to the powerful antioxidant properties of alpha-lipoic acid ().
Though alpha-lipoic acid has been shown to aid blood sugar control, it’s not considered a complete treatment for diabetes. If you have diabetes and want to try alpha-lipoic acid, it’s best to first talk with your doctor, as it may interact with your medications.
Summary Alpha-lipoic acid has been shown to reduce insulin resistance, improve blood sugar control, ease symptoms of nerve damage and lower the risk of diabetic retinopathy.
Alpha-lipoic acid has been linked to a variety of other health benefits.
May Reduce Skin Aging
Research has shown that alpha-lipoic acid may help fight signs of skin aging.
In a human study, scientists found that applying a cream containing alpha-lipoic acid to the skin reduced fine lines, wrinkles and skin roughness with no side effects ().
When alpha-lipoic acid is applied to the skin, it incorporates itself into the skin’s inner layers and offers antioxidant protection against the sun’s harmful UV radiation (19, ).
May Slow Memory Loss
Memory loss is a common concern among older adults.
It’s believed that damage from oxidative stress plays a critical role in memory loss ().
Because alpha-lipoic acid is a powerful antioxidant, studies have examined its ability to slow the progression of disorders characterized by memory loss, such as Alzheimer's disease.
Both human and lab studies have shown that alpha-lipoic acid may slow down the progression of Alzheimer’s disease by neutralizing free radicals and suppressing inflammation (, , ).
However, there are only a handful of studies on alpha-lipoic acid and memory loss-related disorders. More research is needed before alpha-lipoic acid can be recommended for treatment.
Promotes Healthy Nerve Function
Research has shown that alpha-lipoic acid promotes healthy nerve function.
In fact, it’s been found to slow down the progression of carpal tunnel syndrome in its early stages, which is numbness or tingling in the hand caused by a pinched nerve ().
Moreover, taking alpha-lipoic acid before and after surgery for carpal tunnel syndrome has been shown to improve recovery outcomes ().
Studies have also discovered that alpha-lipoic acid may ease symptoms of diabetic neuropathy, which is nerve pain caused by poorly controlled diabetes (, ).
Chronic inflammation is linked to harmful diseases, including cancer and diabetes.
Alpha-lipoic acid has been shown to lower several markers of inflammation.
In an analysis of 11 studies, alpha-lipoic acid significantly lowered levels of the inflammatory marker C-reactive protein (CRP) in adults with high levels of CRP (29).
In test-tube studies, alpha-lipoic acid has reduced markers of inflammation, including NF-kB, ICAM-1, VCAM-1, MMP-2, MMP-9 and IL-6 (, , , ).
May Lower Heart Disease Risk Factors
Heart disease is responsible for 1 in 4 deaths in America ().
Research from a combination of lab, animal and human studies has shown that the antioxidant properties of alpha-lipoic acid may lower several heart disease risk factors.
First, antioxidant properties allow alpha-lipoic acid to neutralize free radicals and reduce oxidative stress, which is linked to damage that can increase heart disease risk ().
What’s more, a review of studies found that taking an alpha-lipoic acid supplement lowered triglyceride and “bad” LDL cholesterol levels in adults with metabolic diseases ().
Summary Alpha-lipoic acid has strong antioxidant properties, which may reduce inflammation and skin aging, promote healthy nerve function, lower heart disease risk factors and slow down the progression of memory loss disorders.
Alpha-lipoic acid is generally considered safe with little to no side effects.
In some cases, people may experience mild symptoms like nausea, rashes or itching.
However, research shows that adults can take up to 2,400 mg without harmful side effects (38).
Higher doses are not recommended, as there’s no evidence that they provide extra benefits.
Not to mention, animal research has found that extremely high doses of alpha-lipoic acid may promote oxidation, alter liver enzymes and place a strain on liver and breast tissue (38, ).
To date, there are very few studies that look at the safety of alpha-lipoic acid in children and pregnant women. People who fall into these categories should not take it unless advised by their doctor.
If you have diabetes, ask your doctor before taking alpha-lipoic acid, as it may interact with other medicines that help lower blood sugar levels.
Summary Alpha-lipoic acid is generally safe with little to no side effects. In some instances, people may experience mild symptoms, such as nausea, rashes or itching.
Alpha-lipoic acid is found naturally in several foods.
Good sources of alpha-lipoic acid include (3):
- Red meats
- Organ meats like liver, heart, kidney, etc.
- Brussels sprouts
- Green peas
- Rice bran
Alpha-lipoic acid is also available as a supplement and can be found in many health stores. Supplements can contain up to 1,000 times more alpha-lipoic acid than foods (3).
Alpha-lipoic supplements are best taken on an empty stomach, as certain foods can lower the acid’s bioavailability (40).
Though there is no set dosage, most evidence suggests that 300–600 mg is sufficient and safe. Alternatively, you can follow the instructions on the back of the bottle.
People with diabetic complications or cognitive disorders may require more alpha-lipoic acid. In such cases, it’s best to ask your doctor how much is most effective.
Summary Alpha-lipoic acid is naturally present in red meats, organ meats and several plants. It’s also available as a dietary supplement sold in health stores.
Alpha-lipoic acid is an organic compound with antioxidant properties. It's made in small amounts by your body but also found in foods and as a supplement.
It may benefit diabetes, skin aging, memory, heart health and weight loss.
Dosages of 300–600 mg seem effective and safe without serious side effects.