Alpha Lipoic Acid: Benefits, Side-Effects, Research and Dosage

Alpha-lipoic acid (ALA) a naturally occurring nutrient in your body. It is important in converting the food that you eat into energy.

ALA is a fatty acid that converts glucose or blood sugar into energy through the aid of oxygen. Aerobic metabolism is a process of converting sugar into energy using oxygen.

A review from the Journal of Parenteral and Enteral Nutrition [1] defines fatty acids as “energy sources and membrane constituents. They have biological activities that act to influence cell and tissue metabolism, function, and responsiveness to hormonal and other signals.”

ALA is also an antioxidant. Antioxidants are important compounds in the body. They neutralize free radicals, substances that damage cells at the genetic and cellular level.

It is absorbed in the gastrointestinal tract quickly and dissolves in fat and water in the body. Although ALA is naturally-occurring in the body, alpha-lipoic acid can also be sourced from the food we eat and through supplementation.

Therapeutic Benefits of ALA and Research

There are several therapeutic uses of ALA. Here are some potential benefits of ALA:

1. Potential treatment of diabetes

Type 2 diabetes is a metabolic disorder that affects more than 400 million people worldwide [2]. It is a chronic condition that affects the body’s ability to appropriately metabolize lipids, carbohydrates, and protein.

Blood sugar levels are high when you have hyperglycemia. The beta cells in the pancreas produce insulin, a hormone responsible for transporting sugar from the bloodstream into the cell. Here, it is metabolized to form energy.

Alpha Lipoic Acid: Benefits, side effects, research and dosage — Photograph: YuriArcursPeopleimages/Envato

When the cells in the body do not appropriately respond to insulin, a condition called insulin peripheral resistance develops. As a result, most cells starve since they do not have enough energy to support the different metabolic pathways in the cell. Meanwhile, destruction of pancreatic cells result in low production of insulin, which in turn results in hyperglycemia.

ALA has been shown to have the potential to treat type 2 diabetes. Findings from previous studies have shown that type 2 diabetes is due to excessive production of reactive oxygen species (ROS). These are free radicals in the cells.

The natural antioxidants in the body could not cope in neutralizing ROS. In turn, type 2 diabetes develops. Animal model studies [3, 4] have shown the potential of ALA in increasing glucose uptake from the bloodstream in both insulin-resistant and insulin-sensitive muscle tissues.

Also, ALA has been studied in humans. A systematic review [5] published in the Metabolism: Clinical and Experimental journal reported that in individuals with metabolic disorders, intake of ALA supplementation significantly reduced blood glucose levels.

Supplementation with ALA improved glycemic control among the patients included in the clinical trials of the review. Importantly, supplementation with ALA decreased total and low density lipoproteins and cholesterol level, and triglycerides. The findings of this review are important since these showed that ALA has the potential to manage type 2 diabetes.

2. Potential in treating nerve pain

Neuropathic pain refers to the pain, abnormal sensations, and numbness caused by damage to the nerves. Oxidative stress is the main cause of nerve damage on the nerves of those with long-term conditions such as Lyme disease, shingles, thyroid disease, HIV and diabetes.

A clinical trial [6] published in the BioMed Pharmacotherapy journal recruited 210 individuals suffering from idiopathic pain. All participants had normal glucose levels and were randomized to receive 800 mg/day of ALA while the second group were randomized to receive 400 mg/day of ALA and the third group received a placebo.

Findings of this study showed that those who received 800 mg/day of ALA reported the greatest reduction of pain scores followed by those in the 400 mg/day group. Those in the placebo group did not report improvements in their pain scores.

The findings of this clinical trial are important in the management of nerve pain. Since ALA supplementation did not result in any adverse events or side effects, ALA may be used as an alternative to NSAIDs or analgesics in treating nerve pain.

When experiencing nerve pain, it is best to consult your doctor if you can safely take ALA to manage pain. When applied to patients with diabetic neuropathy, ALA could be a potential treatment for treating this type of condition. Since ALA has antioxidant properties, it can relieve nerve pain associated with advanced diabetes.

Meanwhile, a systematic review [7] published in the International Journal of Endocrinology pooled results of several clinical trials and found out that intravenous infusion of 600 mg of ALA per day for 21 days helped relieve neuropathic pain. A lower dose of 300 mg of intravenous ALA would also yield positive effects in reducing neuropathic pain.

As shown in another clinical trial [8], intravenous infusion of 300 mg/day to 600 mg/day of ALA for four weeks significantly reduced neuropathic pain in patients with diabetic peripheral neuropathy. These findings are important since these revealed that even lower doses of intravenous ALA could relieve diabetic peripheral neuropathy pain. However, it is unclear if the same dosages, when taken orally would also yield similar benefits.

The findings of these studies help add evidence that ALA could be an effective alternative in reducing neuropathic pain in patients with diabetic peripheral neuropathy and those with long-term conditions that can damage the nerves.

3. Prevention of cataracts

A cataract is described as the opacity of the clear natural crystalline lens of the eye, which results in deterioration of vision. Causes of this condition include aging, diabetes, free radical generation, and oxidative stress.

Notably, antioxidants reduce free radical damage to the eyes. An animal model study [9] evaluated the anti-cataract effects of ALA on goat lenses with induced cataractogenesis. Findings of this study revealed that treatment of eye lenses with 60 micrograms/ml of ALA significantly prevented the formation of cataracts on these eye lenses.

Meanwhile, another model study [10] revealed that ALA and fisetin significantly prevented cataract development in experimental cataract models. These animal model studies provide additional evidence on the potential of ALA in treating cataracts due to oxidative stress or advanced diabetes.

4. Promotion of weight loss

Many weight loss gurus or influencers exaggerate ALA’s ability to burn calories faster. Although clinical trials did show that ALA supplementation can reduce weight, the reduction in weight is not large.

For example, a systematic review funded by Yale and was published in the Obesity Reviews journal [11] demonstrated that supplementation with ALA resulted in an average weight loss of only 1.27 kg. Similarly, another systematic [12] reflected the same results where ALA supplementation resulted in reduction of weight. However, the average weight loss was also small at only 1.5 pounds.

Due to the heterogeneity of the studies, such as differences in the duration of treatment with ALA and the dose of this supplement, it would be difficult to determine if the findings would be applicable to the general population. However, supplementation with ALA could be an important step in your weight loss journey.

These findings confirm that supplementation alone might not be sufficient in losing weight. Instead, there is a need to change diet, lifestyle and increase physical activities to have significant reductions in weight.

5. Potential treatment of Alzheimer’s disease

Memory loss and cognitive impairment are hallmarks of Alzheimer’s disease. Many individuals in the moderate to advanced stages of the disease also have difficulties expressing themselves verbally, while many have wandering and challenging behaviors.

Taking care of individuals with this disease is challenging. Hence, researchers and healthcare practitioners are examining different interventions that might delay the progression of this disease or prevent this from occurring.

Genetics, environment and social factors all play a role in Alzheimer’s. While the exact mechanisms of this disease is not fully clear, current studies suggest that build-up of plaques and amyloids in the brain can cause disruptions in the communication channels of the neurons. Some patients also manifest shrinking areas in the brain involved in memory and higher cognitive functioning.

As an antioxidant, ALA has been studied to determine its protective effects against Alzheimer’s disease. Animal model studies [12] have shown that ALA has neuroprotective effects through neutralizing hydrogen peroxide and other radicals involved in killing cortical neurons. Importantly, animal model studies also showed that ALA tends to increase production of acetylcholine, an important neurotransmitter of the brain that is reduced when an individual has Alzheimer’s disease.

Alzheimer’s disease is also caused by inflammation. Individuals with this disease do not only have elevated levels of free radicals but also increased levels of pro-inflammatory cytokines (compounds responsible for recruiting and activating inflammatory cells into the brain). ALA was shown to prevent inflammation of the brain through scavenging reactive oxygen species (free radicals), transition metal ions that destroy cells, and increasing the levels of reduced glutathione, another antioxidant shown to increase longevity of cells. Further, ALA was also seen to reduce the levels of inflammatory cells.

Although studies supporting the benefits of ALA on Alzheimer’s disease are all animal model studies, the results are promising since these showed that ALA has the potential to treat this disease or prevent it. Since most drugs used to manage Alzheimer’s disease have side effects, using ALA, which has little to no adverse effects, would be safer and more effective for the patients.

Younger patients want to seek natural products to treat their conditions. Hence, use of ALA to potentially treat or prevent Alzheimer’s disease would be acceptable for the next generation.

6. Potential treatment for cancer

More and more studies are looking at ALA’s role in cancer treatment. Cancer cells rely on glucose for energy. However, these cells convert glucose to lactate to generate ATPs or adenosine triphosphate, the energy currency of the cells.

The persistent conversion of glucose to lactate to harvest ATPs can lead to inability of the cells to suppress tumors and activation of oncogenes. As a result, cancer progresses rapidly. Hence, to arrest this cycle, it is necessary to inhibit this type of glucose conversion.

An enzyme called pyruvate dehydrogenase catalyzes the conversion of pyruvate to acetyl CoA, preventing the production of lactate. An animal model study [13] revealed that daily administration of ALA in tumor cells delayed its growth. It was hypothesized that ALA prevented the conversion of pyruvate to lactate, which prevented the proliferation of the tumor cells.

The tumor cells used in the study were neuroblastoma and breast cancer cells. Apart from breast cancer and neuroblastoma cells, ALA was also shown to delay the tumor growth in lung cancer cells, thyroid cancer cells, lung cancer, and colon cancer cells through different mechanisms. All these mechanisms eventually result in cell death, thereby reducing the spread of cancer.

7. Effects of ALA on patients suffering from schizophrenia

Schizophrenia is a mental health condition characterized by hallucinations, many neurocognitive deficits, delusions, memory loss and attention problems. Drugs such as antipsychotic drugs are used to treat this disease.

However, these drugs have side effects including weight gain and obesity and metabolic syndrome. In recent years, clinical trials have been conducted to examine the effects of ALA in reducing side effects of antipsychotic drugs. A systematic review [14] that summarized the findings of clinical trials on ALA and schizophrenia reported that patients who take antipsychotic drugs and ALA supplements experienced fewer to no side effects of the antipsychotic drugs.

In summary, these studies reported reduction in BMI and body weight; reduced visceral fat areas; no severe side effects; minor side effects such as dermatological and gastrointestinal symptoms; significant improvement of neurocognitive parameters; decrease in fasting glucose levels.

The study durations varied from 12 weeks to four months with dosages ranging from 600-1800 mg/day; 100 mg/day; and 500 mg/day of ALA taken orally. It should be noted that the clinical trials included in the systematic review had small sample sizes ranging from 10 patients with stable schizophrenia to 22 patients.

Due to the small sizes, it is difficult to generalize findings to other patients with schizophrenia. However, initial results showed that there is a trend towards use of ALA and reduction of side-effects of antipsychotic drugs.

Supplementing antipsychotic drugs with ALA at 800-1200 mg/day could help optimize the health of these patients and reduce the side effects associated with antipsychotics. Notably, obesity and development of metabolic disorders are serious side effects of antipsychotics since these increase the risk of type 2 diabetes and cardiovascular diseases. Hence, preventing these side effects would reduce the development of comorbid diseases often linked with antipsychotics.

8. Effects of ALA in patients with multiple sclerosis

Multiple sclerosis is a lifelong debilitating disease that affects at least 2.3 million people worldwide. This disease affects the brain and spinal cord and causes a wide range of symptoms.

These symptoms range from problems with balance, sensation, movement of arm and leg, and vision. Symptoms may be mild while others may be debilitating.

The early signs of multiple sclerosis include numbness and tingling; fatigue; stiffness or spasms; loss of balance and dizziness; pain; tremor; bowel trouble; and bladder problems. Some individuals often develop these symptoms at a younger age (20-40 years old). However, others can have late onset multiple sclerosis. In this group, late onset multiple sclerosis can lead to more severe symptoms and faster progression of the disease.

ALA is anti-inflammatory, so it can treat or manage the symptoms of multiple sclerosis (MS). MS is due to multicentric inflammation and loss of myelin sheaths of the nerves in the body and brain.

A clinical trial [15] published in the Neuroimmunomodulation journal revealed that administration of 1200 mg of ALA for 12 weeks significantly reduced inflammatory cells.

The anti-inflammatory effects of ALA reduced symptoms of multiple sclerosis among patients taking the ALA supplements. Initial results showed that walking performance and gait improved with the supplementation.

However, the study had a small sample population. This requires conducting larger trials in the future to confirm results of this small clinical trial. Despite the lack of findings from larger trials on the effects of ALA on symptoms of multiple sclerosis, these initial results showed that ALA could be a promising treatment for symptoms of multiple sclerosis.

9. ALA and stroke and brain function

Alpha-lipoic acid has been shown to easily pass into the brain. This property may help protect nerves and brain tissues.

Hence, it could be a potential treatment for stroke. There are conflicting results on the effects of ALA on brain functioning following a stroke.

For instance, one study [16] found no evidence that ALA could improve antioxidant capacity indices, serum levels of inflammatory cells and albumin in stroke patients. However, another study [17] found that administration of ALA improved functional outcomes of stroke patients.

Although both studies could not be comparable due to differences in the health outcomes investigated, the findings showed that at the molecular level, the effects of ALA may not be seen immediately. Prolonged therapy with ALA might be needed to observe improvements in the functional outcomes of stroke patients.

Other research studies on ALA

Administration of a cream with 5% ALA might reduce fine lines due to sun damage.
Preliminary studies showed that alpha-lipoic acid can bind with toxic chemicals such as iron, arsenic and mercury and other metals that could act as free radicals in tissues.
Preliminary studies suggested that ALA might play a role in managing erectile dysfunction.
Some studies suggested it might address complications due to middle ear infections (otitis media).

What are the dietary sources of ALA?

Although a healthy individual naturally produces ALA sufficient for the body’s needs, there are some individuals who may be deficient in ALA.

Supplementation with ALA is necessary in those who are malnourished or deficient of ALA. Dietary sources of ALA include organ meats such as liver, red meat, and yeast.

Side effects of ALA

At recommended doses, there are no side effects and toxicity risk is very low. However, in isolated or rare cases, some side effects of alpha-lipoic acid can include the following:

Skin rash
Diarrhea
Fatigue
Insomnia

Drug interactions of ALA

Currently, studies have shown that ALA has no known interactions with medicine or food. However, ALA can reduce blood glucose levels and the amount of insulin present.

If you are taking ALA and have diabetes, consult your doctor to ensure that you are taking recommended dosage for alpha-lipoic acid. You should also monitor your blood glucose levels closely.

Apart from interactions with medications for diabetes, ALA may lower thyroid hormone levels. If you are taking thyroid medications such as levothyroxine, always consult your doctor when you are also planning to take ALA. Your doctor can order for thyroid function tests to closely monitor your thyroid hormones.

In addition, alpha-lipoic acid may also reduce vitamin B1 levels in your blood. Hence, it is important to monitor levels of this vitamin when taking ALA.

Recommended dosage

Studies have shown that oral intake of 600-1800 mg of ALA daily for up to six months did not lead to any adverse effects or side effects. Intravenous infusion of ALA at 300-600 mg/day also did not lead to any adverse effects.

However, it is still best to consult with your doctor when planning to take alpha-lipoic acid supplementation to improve your health. Your safety is of primary importance when taking these supplements.

Currently, there are still no studies on the safety of ALA supplementation on pregnant and breastfeeding women. There are also no studies examining the recommended dosage for this group along with the older adults age group and children.

Take home message

Alpha-lipoic acid is a naturally-occurring fatty acid needed by the body to break down glucose, proteins, and fats to fuel the body. It is an essential fatty acid for metabolism and other functions.

To date, there are several studies pointing to the potential benefit of ALA in managing symptoms of type 2 diabetes, Alzheimer’s disease, multiple sclerosis, cancer and other diseases. The anti-inflammatory and antioxidant properties of this compound may be key in preventing the progression of diabetic neuropathy, treatment of neuropathic pain and prevention of cataracts.

Alpha-lipoic acid supplements are available in the market. However, always consult your doctor when you are planning to take this supplement.