Alpha GPC: what is it, benefits, dosage, side effects

last updated: Dec 22, 2021

4 min read

Most people experience a lull in energy and concentration throughout the day. This has led many to look for an answer to the afternoon slump to boost their focus. Alpha GPC is one of the supplements on the market that manufacturers claim increases mental focus and performance. 

Keep reading to learn what alpha GPC is, its potential benefits and risks, along with dosage, side effects, and whether it’s effective. 

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What is alpha GPC?

Alpha-glycerylphosphorylcholine (alpha-GPC), sometimes called alpha-glycerophosphocholine, is a choline-containing compound. It’s found in some foods, supplements, or produced in the body (Marcus, 2017). 

In the U.S., alpha GPC is used as a dietary supplement. In contrast, some European countries use it as a prescription medication.

Alpha GPC can cross the blood-brain barrier, so it helps deliver choline directly to brain cells. The blood-brain barrier is a protective area of cells that prevents most substances from reaching the brain to protect it from pathogens and toxins. Some compounds can move through this filter to reach and affect brain cells.   

It’s believed that taking an alpha GPC supplement may increase levels of the neurotransmitter acetylcholine in the brain. Acetylcholine is involved in muscle contraction, blood vessel health, heart rate, and other functions (Marcus, 2017). 

What is alpha GPC used for?

Alpha GPC is considered a type of nootropic, which is a group of substances that may boost cognitive function and mental performance. Nootropics can be medications or supplements. 

The Food and Drug Administration (FDA) hasn’t approved alpha GPC for medical uses or treatment of medical conditions because there isn’t enough scientific evidence to prove the effectiveness of this supplement for health problems. 

Still, there are some short term and animal studies that have led people to believe alpha GPC may be beneficial for:

  • Alzheimer’s disease and vascular dementia—Some research suggests alpha GPC may improve cognitive function, slow the progression of cognitive decline, and improve symptoms related to Alzheimer’s disease (DeFina, 2013).   

  • Stroke recovery—A 2008 animal study found that alpha GPC may help reduce cell damage (Onishchenki, 2008). However, another cohort study found that individuals who took alpha GPC may be at a higher risk for stroke (Lee, 2021).

  • Epilepsy—In one animal study, alpha GPC was found to reduce the death of neurons and support the blood-brain barrier. The researchers believe the supplement may help improve cognitive function in people with epilepsy (Lee, 2017).

Benefits of alpha GPC

As you can probably tell, most of the research behind alpha GPC’s benefits is not exactly strong enough to rely upon. Just because it appears to have certain effects in animals and small sample sizes, that doesn’t mean it would have the same impacts on humans on a large scale. 

Still, many of the proposed benefits of alpha GPC are likely related to possible increases in the neurotransmitter acetylcholine. 

It’s believed that acetylcholine plays a role in memory and learning through its effects on brain health. Another function of acetylcholine is assisting in regulating heart rate and blood pressure, which may improve blood flow and slow heart rate (Sam, 2021). 

Here are some of the possible benefits of alpha GPC (Sam, 2021; Bellar, 2015):

  • May boost memory and cognitive function 

  • May improve blood flow to the brain

  • May improve thinking skills and learning abilities

  • May boost muscle and athletic performance

Again, more high-quality research is needed to confirm whether these potential benefits can reliably occur.

Alpha GPC dosage

There is no specific dose recommended for alpha GPC. The best dose likely depends on your desired effect, age, health, and medical history. 

In 2012, the FDA stated the amount of alpha GPC consumed through food sources of choline and supplements is generally considered safe at levels below 196.2 mg of alpha GPC per day (LSRO, 2012). 

It should be noted that the FDA doesn’t fully regulate dietary supplements, so be sure to research the company and claims before starting a supplement. Talk with a healthcare professional for medical advice before starting any new supplements to discuss benefits, risks, and dose. 

Side effects of alpha GPC

Alpha GPC is likely safe when used appropriately and in low doses, but it can lead to mild side effects such as:

  • Heartburn

  • Headaches

  • Insomnia

  • Confusion

  • Skin rash or redness

  • Dizziness

Another potential side effect of alpha GPC is it could increase the risk for strokes. A 2021 study assessed the effects of alpha GPC on stroke risk over ten years. The study found that alpha GPC users were at a higher risk for a stroke than non-users. They also found that higher doses of alpha GPC increased the risk for stroke (Lee, 2021).

Is alpha GPC effective?

More research is needed to understand the true effects of alpha GPC. Much of the research and clinical studies were done for short periods of time or are animal studies, so it’s difficult to know how the supplement affects people over time. 

In addition, the 2021 cohort study showing increased stroke risk brings into question the safety of the supplement. 

Not all research studies support the effectiveness of alpha GPC. A 2015 clinical trial didn’t find any statistically significant benefits of alpha GPC on mood, brain function, or physical performance compared to caffeine or the placebo (Parker, 2015).There is potential the supplement could be effective and have benefits for the brain. But more research is needed to prove the effectiveness and safety of alpha GPC. Contact your healthcare provider with any questions and concerns about alpha GPC before taking it.


If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.

  • Bellar, D., LeBlanc, N. R., & Campbell, B. (2015). The effect of 6 days of alpha glycerylphosphorylcholine on isometric strength. Journal of the International Society of Sports Nutrition , 12 , 42. doi: 10.1186/s12970-015-0103-x. Retrieved from

  • Defina, P. A., Moser, R. S., Glenn, M., Lichtenstein, J. D., & Fellus, J. (2013). Alzheimer's disease clinical and research update for health care practitioners. Journal of Aging Research , 2013 , 207178. doi: 10.1155/2013/207178. Retrieved from

  • Lee, G., Choi, S., Chang, J., Choi, D., Son, J. S., Kim, K., et al. (2021). Association of L-α Glycerylphosphorylcholine With Subsequent Stroke Risk After 10 Years. Journal of the American Medical Association Network Open , 4 (11), e2136008. doi: 10.1001/jamanetworkopen.2021.36008. Retrieved from

  • Lee, S. H., Choi, B. Y., Kim, J. H., Kho, A. R., Sohn, M., Song, H. K., et al. (2017). Late treatment with choline alfoscerate (l-alpha glycerylphosphorylcholine, α-GPC) increases hippocampal neurogenesis and provides protection against seizure-induced neuronal death and cognitive impairment. Brain Research , 1654 (Pt A), 66–76. doi: 10.1016/j.brainres.2016.10.011. Retrieved from

  • Life Sciences Research Office (LSRO). (2012). Generally recognized as safe (GRAS) determination for use of AlphaSizeⓇ alpha-alycerylphosphorylcholine. Retrieved from

  • Marcus, L., Soileau, J., Judge, L. W., & Bellar, D. (2017). Evaluation of the effects of two doses of alpha glycerylphosphorylcholine on physical and psychomotor performance. Journal of the International Society of Sports Nutrition , 14 , 39. doi: 10.1186/s12970-017-0196-5. Retrieved from

  • Onishchenko, L. S., Gaikova, O. N., & Yanishevskii, S. N. (2008). Changes at the focus of experimental ischemic stroke treated with neuroprotective agents. Neuroscience and Behavioral Physiology , 38 (1), 49–54. doi: 10.1007/s11055-008-0007-1. Retrieved from

  • Parker, A. G., Byars, A., Purpura, M., & Jäger, R. (2015). The effects of alpha-glycerylphosphorylcholine, caffeine or placebo on markers of mood, cognitive function, power, speed, and agility. Journal of the International Society of Sports Nutrition , 12 (Suppl 1), P41. doi: 10.1186/1550-2783-12-S1-P41. Retrieved from

  • Sam, C. & Bordoni, B. (2021). Physiology, Acetylcholine. [Updated 2021, April 17]. In: StatPearls [Internet]. Retrieved on Dec. 16, 2021 from

How we reviewed this article

Every article on Health Guide goes through rigorous fact-checking by our team of medical reviewers. Our reviewers are trained medical professionals who ensure each article contains the most up-to-date information, and that medical details have been correctly interpreted by the writer.

Current version

December 22, 2021

Written by

Ashley Braun, RD, MPH

Fact checked by

Steve Silvestro, MD

About the medical reviewer

Dr. Steve Silvestro is a board-certified pediatrician and Associate Director, Clinical Content & Education at Ro.