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What Is Soy Lecithin? Potential Benefits vs. Risks
December 18, 2022
If you read your food labels, I’m sure that you’ve run across the ingredient “soy lecithin” because it’s one of the most widely used food additives on the market today.
Soy lecithin is widely found in both conventional and health food stores. It’s often used as an ingredient in food products and is sold in supplement form to boost your health.
Yet, surprisingly, there is a lot of confusion (and maybe even prejudgment) about soy lecithin because it includes the word “soy.”
So, what is soy lecithin, and is it good for me?
The bottom line is that there are pros and cons to consuming soy lecithin, but it’s definitely not as bad as some make it out to be. When you choose the right soy lecithin products, it actually boasts potential health benefits, such as its ability to lower cholesterol levels and boost brain function.
However, the soy lecithin world can be tricky, as it is indeed made from soy, a food that I typically try to avoid unless it’s fermented.
Keep reading to learn more about how soy lecithin is made and whether or not it should be avoided like many other soy products on the market today.
What Is Soy Lecithin?
When seeking to answer the question, “What is soy lecithin?” our search immediately takes us to mid-19th century France. First isolated by French chemist Theodore Gobley in 1846, lecithin is a generic term to designate a variety of naturally occurring fatty compounds found in animal and plant tissues.
Composed of choline, fatty acids, glycerol, glycolipids, phospholipids, phosphoric acid and triglycerides, lecithin was originally isolated from egg yolk. Today, it is regularly extracted from cottonseed, marine sources, milk, rapeseed, soybeans and sunflower.
It is usually used as a liquid but can also be purchased as lecithin granules.
By and large, the vast majority of lecithin use centers around its usefulness as an excellent emulsifier.
We know that oil and water don’t mix, right? When the two are placed into a solution and shaken together, the oil droplets initially spread out and appear to evenly disperse, but once the shaking stops, the oil separates from the water again.
This is exactly why lecithin is so important and often used as an additive in processed foods, medicine and supplements.
When lecithin enters the equation, oil is broken down into smaller particles in a process called emulsification, making the oil droplets easier to clean or digest when eaten. Thus, lecithin helps give products a smooth, uniform appearance.
Additionally, its ability to emulsify fats makes it an ideal ingredient for nonstick cooking sprays and soaps.
Soy in Soy Lecithin
Soy lecithin is extracted from raw soybeans, so if you’re wondering if it contains soy, the answer is yes. First the oil is extracted using a chemical solvent, like hexane, and then the oil is processed (which is called degumming) so the lecithin is separated and dried.
It appears that soy lecithin only contains trace levels of soy proteins. For this reason, researchers believe that soy lecithin will not provoke allergic reactions in the majority of soy-allergic consumers because it does not contain sufficient soy protein residues.
You see, the soybean allergens are found in the protein fraction, which is almost entirely removed in the soy lecithin manufacturing process. The Institute of Agriculture and National Resources at the University of Nebraska-Lincoln suggests “many allergists do not even advise their soybean-allergic patients to avoid soybean lecithin when it is included as an ingredient on food products.”
Do use caution when eating any product containing soy, though. People with more sensitive soybean allergies still may react negatively to soy lecithin ingestion and will have to be more conscious of packaged foods containing this ingredient.
Another widely researched issue regarding soy is that it contains isoflavones or phytoestrogens, which are naturally occurring estrogenic compounds. Although isoflavones are found in many different plant foods, soybeans contain uniquely rich amounts.
In soybeans, isoflavones occur almost exclusively as glycosides (sugar compounds), but once the soy food is ingested, the sugar is hydrolyzed and can be absorbed by the body.
Isoflavones have a chemical structure that’s similar to the hormone estrogen, so they can bind to estrogen receptors and cause estrogen-like effects on the body. That’s at least what some animal studies have shown us, but there is definitely more research to be done on this topic to fully understand the role that consuming isoflavones has on our health.
Although consuming isoflavones may have potential health benefits, like improving menopause and osteoporosis symptoms, there are concerns about their estrogen-like properties and how they affect the thyroid, uterus and breasts, according to an evaluation of the clinical and epidemiologic literature on this subject that was published in Nutrients.
Personally, when I do eat soy, I only go for fermented soy products, like miso and tempeh. They may be beneficial to your health because they:
- are excellent sources of dietary protein
- contain all of the essential amino acids
- are easier to digest
Plus, the fermentation process breaks down the antinutrients that are present, and they contain probiotics.
Natto, for example, is a dish that contains fermented soybeans, and I consider it one the greatest probiotic foods because it has been proven to help reduce inflammation and support your immune system.
Oftentimes extracted from soybean oil, one ounce (28 grams) of soybean lecithin has the following nutritional content:
- 214 calories
- 28 grams fat
- 1,438 milligrams omega-3 fatty acids
- 11,250 milligrams omega-6 fatty acids
- 51.5 micrograms vitamin K (64 percent DV)
- 2.3 milligrams vitamin E (11 percent DV)
- 98 milligrams choline
Why are lecithin supplements so popular, and what are soy lecithin capsules used for? The answer lies in the fact that lecithin supplements contain a complex mixture of phospholipids, which compose the cellular membrane structure and are used for energy storage.
Two types of phospholipids that are essential components for biological membranes include phosphatidycholine and phosphatidylserine.
Researchers in Japan found that the administration of fresh phospholipids can work to replace damaged cell membranes and restore the structure and function of the cellular membrane. This is called lipid replacement therapy, and it has been shown to improve fatigue, diabetes symptoms, degenerative diseases and metabolic syndrome.
Phosphatidylcholine is one of the primary forms of choline and acts as an essential component in cell membrane signaling. Phosphatidylcholine is produced in the liver and converted into choline, which plays several important processes within the body.
Phosphatidylserine is found in the membranes of all animals, higher plants and microorganisms. In humans, it’s most concentrated in the brain, and phosphatidylserine supplementation is often used to improve brain function in elderly patients.
Research also shows that it might be beneficial for children and young people with ADHD and mental health conditions.
Risks and Side Effects
Although there are a number of potential benefits from consuming soy lecithin, there are also some dangers and side effects that you should be aware of before choosing to ingest foods or supplements containing this ingredient.
When determining soy lecithin side effects and safety, it’s important to consider the extraction process that’s required to get the emulsifier from soybeans.
Hexane is a solvent that’s used to extract oils from seeds and vegetables. It’s also used as a solvent for glues and varnishes and as a cleaning agent in the printing industry.
Hexane is used in the extraction process when separating the lecithin from the soybean, and then it is removed through another multi-step process.
There can be hexane residue leftover, however, and this is not regulated by the U.S. Food and Drug Administration. That means we don’t know exactly how much hexane may be in the soy lecithin that you’re eating, and the Environmental Protection Agency lists a number of dangerous side effects of hexane inhalation exposure, which reportedly include mild central nervous system effects like dizziness, nausea and headaches.
Another potential issue with soy lecithin is that unless it’s labeled as “organic soy lecithin,” it probably comes from genetically modified soybeans.
Is soy lecithin genetically modified? Well, generally speaking, since soy lecithin is extracted from soy oil, which is almost always generically modified, the answer is usually yes.
A major issue is that the original source for soy lecithin is nearly impossible to tract down, so it can very well come from GMO soy and you wouldn’t know it.
Potential Estrogenic Effects
The science about isoflavones and their estrogenic effects still isn’t clear. There is animal research indicating that consuming high amounts of soy phytoestrogens can reduce testosterone levels, but there’s also evidence that soy consumption has no effect on hormone levels in men.
People with thyroid issues should try to limit soy consumption because studies have found that it may decrease the production of thyroid hormones in the body.
People with sensitive soy allergies may have an adverse reaction to soy lecithin, and in many cases, it’s made from genetically modified soy.
A 2020 study published in the Journal of Human Nutrition and Dietetics evaluated whether children with soy allergies reacted to soy lecithin in food products. Twenty children participated in the study, and they were randomly assigned to either a placebo or challenge dose of soy lecithin. One child had a slight reaction to the emulsifier.
These results are likely because soy lecithin only contains trace levels of soy proteins. Although the ingredient is likely safe, people with severe allergies to soy should avoid foods made with soy lecithin.
1. Improves Cholesterol Levels
Dietary soy lecithin supplementation is most strongly connected with decreasing hyperlipidemia and influencing lipid metabolism. It’s known for its important role in processing fat and cholesterol, which is why people sometimes take soy lecithin supplements to lower cholesterol naturally.
Research suggests that properties of lecithin have the ability to reduce the excess of LDL cholesterol and promote the synthesis of HDL in the liver.
A 2010 study published in the journal Cholesterol evaluated total cholesterol and LDL levels after soy lecithin administration in patients with diagnosed hypercholesterolemia levels. For the study, one 500-milligram soy lecithin supplement was taken by 30 volunteers every day, and the results were quite astounding.
Researchers found the following to be true after patients supplemented with soy lecithin:
- A reduction of 41 percent in total cholesterol after 1 month
- A reduction of 42 percent in total cholesterol after 2 months
- A reduction of 42 percent in LDL after 1 month
- A reduction of 56 percent in LDL after 2 months
This study suggests that soy lecithin may be used as a dietary supplement for the treatment of hypercholesterolemia.
2. Serves as a Source of Choline
Soy lecithin contains phosphatidylcholine, which is one of the primary forms of choline, a macronutrient that plays an important role in liver function, muscle movement, metabolism, nerve function and proper brain development.
Researchers at the University of Wales Swansea revealed that phosphatidylcholine supplementation has been found to support healthy cholesterol levels, liver function and brain function. Many of the potential benefits of soy lecithin powder or supplements come from the choline content.
3. May Boost Immunity
Soy lecithin supplementation has been shown to significantly boost immune function among diabetic rats. Brazilian researchers discovered that daily supplementation with soy lecithin caused macrophage activity (white blood cells that engulf foreign debris) of diabetic rats to increase by 29 percent.
Additionally, they discovered that lymphocyte (white blood cells that are fundamental to the immune system) numbers skyrocketed 92 percent in non-diabetic rats. This suggests that, at least in rats, soy lecithin has immunomodulatory effects.
More research is needed to conclude the role of soy lecithin in the human immune system.
4. Helps Body Deal with Physical and Mental Stress
One of the many keys to soy lecithin’s health benefits is a compound known as phosphatidylserine — a common phospholipid that helps make up part of the cell membranes in plants and animals. Known to affect stress hormones adrenocorticotropic hormone (ACTH) and cortisol, phosphatidylserine derived from cow brains has been shown to dampen response to physical stress.
Testing to see how phosphatidylserine derived from soy lecithin compared, German researchers evaluated the effects that soy lecithin phosphatidic acid and phosphatidylserine complex (a combination referred to as PAS) supplementation has on ACTH, cortisol and a psychological evaluation known as the Spielberger State Anxiety Inventory stress subscale.
Published in the Danish journal Stress, the trial compared 400 milligrams, 600 milligrams and 800 milligrams of PAS on groups of 20 people each. The researchers not only discovered that PAS has some pretty remarkable effects on the human psyche, but they uncovered that it is dose-dependent.
They found a sweet spot with the 400 milligrams of PAS because it is considerably more effective at blunting serum ACTH and cortisol levels than the larger doses.
This study suggests that specific properties in soy lecithin may have a selective stress-dampening effect and may even be used in the natural treatment of stress-related disorders.
5. May Improve Cognitive Function
A three-month, double-blind, placebo-controlled study published in Advances in Therapy evaluated the positive effects of a supplement containing a blend of 300 milligrams of phosphatidylserine and 240 milligrams of phosphatidic acid that was produced from soy lecithin.
The supplement or placebo was given to non-depressive elderly patients with memory problems three times a day for three months. In a separate investigation, the supplement was given to patients with Alzheimer’s disease to measure its effect on their daily functioning, mental health, emotional state and self-reported general condition.
Researchers found that by the end of the treatment period, the supplement blend made from properties found in soy lecithin significantly improved memory and prevented the “winter blues” in elderly patients compared to those receiving the placebo.
Among the Alzheimer’s disease patients, the supplement group had a 3.8 percent deterioration and 90.6 percent stability in daily functioning compared to 17.9 percent and 79.5 percent under the placebo. Plus, 49 percent of those in the treatment group reported an improved general condition compared to 26.3 percent of those receiving the placebo.
These findings suggest that soy lecithin-derived phosphatidylserine and phosphatidic acid may have a positive influence on memory, cognition and mood among the elderly and those suffering from cognitive conditions.
6. May Prevent Osteoporosis
Although the research is mixed, there are studies indicating that soybean and soy-based ingredients, including soy lecithin, act as antiresorptive and bone-enhancing agents in preventing osteoporosis. This is due to the isoflavones found in soy, specifically the glycosides.
According to a scientific review published in the Journal of Medicinal Food, epidemiologic studies have found that elderly Asian women have a lower incidence of hip fractures than Caucasian women, and further research indicates that the consumption of soy products is much higher among Asians than caucasians.
Researchers state that soy-based products could “potentially lower the bone loss rate and decrease the risk of fracture.” This may be due to soy’s estrogenic effects, as estrogen deficiency induced by menopause has been shown to accelerate bone loss in older women.
It also may be due to properties in soy (notably the glycosides) that have antioxidant, antiproliferative, estrogenic and immune-modulating effects.
7. Relieves Menopause Symptoms
In addition to its potential benefit for osteoporosis, research suggests that soy lecithin supplements may help improve menopause symptoms by improving vigor and blood pressure levels in menopausal women. A 2018 randomized, double-blind, placebo-controlled study including 96 women between the ages of 40 to 60 sought to investigate whether or not soy lecithin supplements could help to relieve symptoms of fatigue.
The participants were randomized to receive active tablets containing high-dose (1,200 milligrams per day) or low-dose (600 milligrams per day) soy lecithin or a placebo for an eight-week period.
Researchers found that the improvements in fatigue symptoms, diastolic blood pressure and cardio-ankle vascular index (to measure arterial stiffness) were greater in the high-dose group compared with the placebo group.
8. May Help Prevent Cancer
A 2011 study published in the journal Epidemiology found that there may be a reduced risk of breast cancer associated with lecithin supplement use. Researchers weren’t able to make any conclusive statements about it being able to treat cancer but suggested that their findings should be considered “hypothesis-generating.”
This link between soy lecithin and decreased breast cancer risk may be due to the presence of phosphatidylcholine in soy lecithin, which is converted to choline when ingested.
How to Avoid It
People with severe allergies to soy products or those who are sensitive to soy lecithin should avoid foods made with the ingredient. For those who don’t experience side effects from eating the emulsifier but want to avoid consuming GMO foods, opt for choosing only organic foods with soy lecithin on the label.
Some products are made with other types of emulsifiers that can be considered safer ingredients. Sunflower lecithin is a good alternative, and egg yolks can have a similar effect in food products.
- Lecithin is a generic term to designate a variety of naturally occurring fatty compounds found in animal and plant tissues. Soy lecithin, in particular, is extracted from soybeans and often used as an emulsifier.
- Soy lecithin is composed of choline, fatty acids, glycerol, glycolipids, phospholipids, phosphoric acid and triglycerides. It contains very little soy protein, so it’s generally considered safe for people with soy allergies.
- Soy lecithin also has potential health benefits, including its ability to:
- improve cholesterol
- serve as a source of choline
- boost immunity
- help the body deal with mental and physical stress
- improve cognitive function
- prevent osteoporosis
- relieve menopause symptoms
- possibly reduce the risk of cancer
- Although there are many potential health benefits of soy lecithin, it is still commonly derived from genetically modified soy, so look for organic options whenever possible. Also, keep in mind that soy lecithin contains isoflavones, which can have estrogenic-effects when ingested.