Phosphatidylcholine (PC) is a phospholipid attached to a choline particle. Phospholipids contain fatty acids, glycerol, and phosphorous.

The phosphorous part of the phospholipid substance — the lecithin — is made up of PC. For this reason, the terms phosphatidylcholine and lecithin are often used interchangeably, although they’re different. Foods that contain lecithin are the best dietary sources of PC.

Although PC is traditionally used to support brain health, it can also support liver function and keep cholesterol levels in check. Read on to learn what the research says about the benefits of this nutritional supplement.

According to a 1995 study on mice with dementia, PC supplementation can increase the neurotransmitter acetylcholine in the brain. It may also improve memory. The study found that mice without dementia had no memory increase, despite the increase in acetylcholine levels.

A 2001 study found feeding mice a diet rich in PC and vitamin B-12 also had a positive impact on brain health. Although these results are promising, more study is needed.

Research has continued, and a 2017 study has found that levels of phosphatidylcholine are directly related to Alzheimer’s disease.

A high-fat diet is known to negatively affect the liver. It may cause nonalcoholic fatty liver disease or cirrhosis of the liver. According to a 2010 study, PC helped reduce lipids that can lead to a fatty liver (hepatic lipids) in mice fed a high-fat diet.

Another study on mice reviewed whether bringing elevated levels of PC back to normal helps prevent nonalcoholic fatty liver disease. The study found that it helped prevent the accumulation of fat in the liver. It did not, however, prevent nonalcoholic fatty liver disease.

Some medications, such as nonsteroidal anti-inflammatory drugs (NSAIDs), can cause severe gastrointestinal side effects with extended use. This includes stomach pain, gastric bleeding, and intestinal perforation.

According to a 2012 study, long-term NSAID use may disrupt a phospholipid layer of the gastrointestinal tract. This may cause gastrointestinal injury. Research has shown that PC may help prevent NSAID-related gastrointestinal damage.

Ulcerative colitis causes inflammation in the digestive tract. It may also cause ulcers. According to a 2010 study, people with ulcerative colitis often have reduced levels of PC in their intestinal mucus. Supplementation may help protect the mucus layer of the digestive tract and reduce inflammation.

Lipolysis is the breakdown of fats in the body. Too much fat may cause lipomas to form. Lipomas are painful, benign fatty tumors. Most are removed surgically.

According to a 2014 study, injecting PC into a lipoma can kill its fat cells and reduce its size. More study is needed to determine the long-term safety of this treatment.

Gallstones are hard deposits in your gallbladder. They’re usually made of undissolved cholesterol or bilirubin. If left untreated, they may become lodged in your bile ducts and cause severe pain or pancreatitis.

According to a 2003 study, PC supplementation reduced cholesterol gallstone formation in mice fed a high-cholesterol diet. The study found that when PC levels increased, cholesterol saturation levels decreased.

There are many brands of PC to choose from, but they’re not all created equal. Because supplements aren’t well-regulated, it can be challenging to know if you’re getting a high-quality product.

You should choose a brand that:

  • is made in a GMP (Good Manufacturing Practices) facility
  • is made with pure ingredients
  • contains few or no additives
  • lists active and inactive ingredients on the label
  • is tested by a third party

There’s no standardized dosage recommendation for PC for most conditions. A common dose is 840 milligrams up to twice daily, but you should always defer to the dosage provided on the product. Your doctor can also help you determine a safe dosage for you.

To reduce your risk of side effects, start with the lowest dose possible and gradually work your way up to a full dose. Be sure to follow the manufacturer’s guidelines or your doctor’s instructions.

Oral PC may cause excessive sweating, and taking more than 30 grams daily may cause:

  • diarrhea
  • nausea
  • vomiting

Injecting PC directly into a fatty tumor may cause severe inflammation or fibrosis. It may also cause:

  • pain
  • burning
  • itching
  • bruising
  • edema
  • reddening of skin

Taking PC with an AChE inhibitor, such as donepezil (Aricept) or tacrine (Cognex), may increase acetylcholine levels in the body. This may cause cholinergic side effects, including:

  • seizures
  • muscle weakness
  • slow heartrate
  • breathing problems

Taking PC with cholinergic or anticholinergic drugs may also impact their effectiveness.

PC has not been proven safe for women who are pregnant or breastfeeding, and it’s therefore not recommended.

PC helps support many of your body’s functions, ranging from fat metabolism to maintaining cell structure. You can get enough from foods such as eggs, red meat, and whole grains, and food sources are the best first choice. Supplements are the second option. Choose your brand after doing research on reputation and quality, as supplements are not regulated by the U.S. Food and Drug Administration.

PC supplements are available in capsule and liquid forms without a prescription. They’re thought to be safe when used as directed for short periods of time. Injectable PC must be administered by a health professional.

If you’d like to add PC to your routine, talk to your doctor. They can walk you through your individual benefits and risks, as well as answer any questions you may have.