Soy lecithin is a supplement taken primarily for its cholesterol lowering effects and for its ability to improve heart health and digestion.
Soy lecithin is a substance derived from soy that is composed of fatty acids and small amounts of proteins and carbohydrates. Its main component — phosphatidylcholine — is a source of choline, an important nutrient that is critical for several purposes in the human body: cell membrane signaling; synthesis of the neurotransmitter acetylcholine (which is necessary for brain and muscle function); fat transportation and keeping the fats circulating in the blood in balance.
Growing studies show lecithin’s potential to treat a range of other medical conditions as well.
Soy lecithin may improve cholesterol levels. Cholesterol is the waxy, fat-like substance that your body needs (in certain amounts) to make hormones, vitamin D and substances that help digest foods. Excessive amounts can be problematic (1).
Cholesterol is categorized as: low-density lipoprotein (LDL) or high-density lipoprotein (HDL). LDL is considered “bad” because it contributes to fatty buildup in arteries and increases the risk for heart attack and stroke. HDL is the “good” type due to its ability to transport bad cholesterol away from the arteries and back to the liver, where it is broken down and passed from the body (2).
Recent studies show soy lecithin’s potential in improving cholesterol levels. In a 2010 study, total cholesterol and LDL were evaluated after soy lecithin administration in patients with elevated cholesterol levels.
The study revealed that one 500mg soy lecithin capsule taken daily showed a reduction of 40.66 percent and 42.00 percent in total cholesterol and of 42.05 percent and 56.15 percent in LDL cholesterol after treatment for one and two months, respectively (3).
In another study, the cholesterol-lowering effect of lecithin-enriched diets was associated with significantly lower levels of plasma total cholesterol and significantly higher levels of bile phosphatidylcholine (4).
Soy lecithin may help reduce stress. In a study of four groups of 20 participants, researchers evaluated the effects of soy lecithin phosphatidic acid and phosphatidylserine complex (PAS) supplementation on the psychological response to a mental and emotional stressor.
The groups were treated for three weeks with daily dosages of either 400mg PAS, 600mg PAS, 800mg PAS or placebo before exposure to the Trier Social Stress Test (TSST).
400mg PAS seemed to exert a specific positive effect on emotional responses to the stress test. While the placebo group showed the expected increase in distress after the test, the group treated with 400 mg PAS showed the most decreased distress.
Soy lecithin may help treat memory loss. The goal of a recent Japanese study was to evaluate the effect of different types of dietary lipids on longevity and age-related deterioration in memory in mice.
Eight-month-old mice were fed diets with 5 percent lard, 5 percent soybean oil, 2 percent lecithin plus 3 percent soybean oil, or 2 percent fish oil plus 3 percent soybean oil; learning and memory were examined by passive avoidance test.
Results of the study indicated that group of soy lecithin (at 2 percent of the diet with 3 percent coming from soy oil) as associated with more survival than lard when measured at 12 months. In addition, the lecithin outperformed all other groups in a cognitive test of aging (7).
Other reports of lecithin’s potential to treat memory loss are mixed, however.
In a meta-analysis of the use of lecithin in the treatment of patients with dementia, authors of the analysis concluded that while supplementation had a slight effect, the findings were not impressive enough to prioritize further research at this time (8).
Soy lecithin may help enhance the efficacy and safety of some drugs and herbs. Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used over-the-counter medications for the treatment of pain and inflammation. Due to the potential for heartburn, stomach pain and ulcers when using these drugs excessively or chronically, researchers are seeking safer alternatives.
According to the results of a study published in Inflammopharmacology, an oil-based formulation of naproxen (common nonsteroidal anti-inflammatory drug) and triple strength soy lecithin provided excellent gastrointestinal protection.
The napoxen and soy lecithin formulation appeared to induce significantly less gastrointestinal injury and bleeding in two rodent model systems, while effectively treating rats with hind paw inflammation (9).
Soy Lecithin helps treat ulcerative colitis. Ulcerative colitis is a chronic disease of the large intestine (colon) in which the lining of the colon becomes inflamed and develops tiny ulcers. The inflammation and ulceration can cause abdominal discomfort and frequent emptying of the colon (10).
Lecithin (phosphatidylcholine) has been shown to account for more than 70 percent of total phospholipids within the intestinal mucus layer. It establishes a hydrophobic barrier preventing invasion of microbiota. In ulcerative colitis, the mucus content is demonstrated to be significantly reduced. This is what researchers believe allows bacteria to enter the mucus and induce mucosal inflammation.
Growing evidence shows that lecithin improves the mucus in the intestine, making the digestive process easier while protecting the delicate lining of the colon (11).
Lecithin may cause diarrhea, nausea or abdominal pain (12).
Those with a soy allergy should be cautious before taking soy lecithin supplements. Some studies also show that daily dosage of soy lecithin may clot the blood (13).
Dosages used in studies typically range between 500-2,000mg. More human trials are needed before an optimal dosage can be recommended.
Soy lecithin is a substance derived from soy that is composed of fatty acids and small amounts of proteins and carbohydrates. Its main component — phosphatidylcholine — is a source of choline which is an important nutrient involved in the synthesis of the neurotransmitter acetylcholine (which is necessary for brain and muscle function), and keeping the fats circulating in the blood in balance.
Early evidence shows lecithin’s potential for improving cholesterol levels, protecting the gastrointestinal tract in those with ulcerative colitis and helping safeguard the stomach against damage from NSAIDs.
Supplementation also has the possibility to treat stress-related disorders and age-related memory deterioration.
While further in-depth studies and human clinical trials are needed, preliminary findings of this supplement are promising.