Evidence: High Possible Benefits: Very High Safety: High
TABLE OF CONTENTS
What is soy lecithin?
Soy lecithin is a fatty substance extracted from soybean. It is commonly used as a dietary supplement for its high phosphatidylcholine and phosphatidylserine levels, which can have a wide variety of benefits. This article is about the main benefits of soy lecithin, its potential side effects, the best time to take it, and more.
Possible benefits
All of the potential benefits mentioned below are dose-dependent. As with most other supplements, there is a sweet-spot dose that allows you to get most of the benefits without causing meaningful side effects or tolerance buildup in the body. We will discuss the best dosing protocol later in this article.
Major benefits
Improved cholesterol levels – One human study showed lecithin can reduce LDL cholesterol levels by about 50% in hypercholesterolemia, which is a remarkable improvement. HDL cholesterol appears mostly unaffected by the supplement.
Improved cognition – Phosphatidylcholine in soy lecithin can greatly improve memory, attention, reaction time, and more aspects of cognition by supporting the acetylcholine pathways. Phosphatidylserine is also associated with an improvement in many areas of cognition, including memory, learning capacities, attention, mental flexibility, number processing, calculation, and more. Supplementation can support acetylcholine release, monoamine oxidase B (MAO-B), brain glucose metabolism, and increase BDNF (brain-derived neurotrophic factor).
Correcting or preventing a choline deficiency – Choline deficiency can be terrible for your health and overall quality of life. Fortunately, a severe deficit is relatively rare. A mild deficiency is much more common and can lead to many health problems, such as low energy, forgetting and poor memory, difficulty concentrating, muscle aches, and mood swings. If you are experiencing symptoms of deficiency or know that your choline levels are too low, correcting a deficiency is probably the main benefit of soy lecithin.
Reduced symptoms of schizophrenia – Phosphatidylserine from soy lecithin can be about as effective as glycine and sarcosine for reducing the symptoms of schizophrenia. It is not as reliable as sarcosine as many people don’t respond to phosphatidylserine supplements positively. On the other hand, phosphatidylserine is much more practical than glycine for this purpose because glycine can only reduce symptoms of schizophrenia when taken at extremely high doses (800+ mg/kg/d). This dose seems too impractical and may not be safe to take in the long term.
Minor benefits
Reduced stress and anxiety – Soy lecithin has a mild cortisol-lowering effect, which can induce calmness and relaxation and reduce stress and anxiety. This benefit was shown in human studies on both lecithin and its active component phosphatidylserine.
Improved well-being – At least one study has shown that phosphatidylserine supplements can reduce the intensity of sad feelings and supports healthy stress response.
Reduced addiction rates – This effect was mainly studied in cocaine addicts where CDP-choline was able to lower addiction rates among those who wanted to quit using the substance. Since CDP-choline breaks down into phosphatidylcholine in the body and soy lecithin contains high amounts of phosphatidylcholine, this benefit almost certainly applies to soy lecithin as well. While it has not yet been fully proven, cholinergics appear to be quite effective at helping people get through addictions to other substances and activities.
Reduced symptoms of Parkinson’s disease – While more research is necessary to prove this effect, at least one study shows that D-serine can alleviate some symptoms of Parkinson’s disease. This effect likely applies to phosphatidylserine and therefore soy lecithin as well.
Increased exercise performance – Phosphatidylserine supports resistance to exhaustion and healthy stress responses to exercise.
Reduced folate and vitamin B12 deficiency – Phosphatidylcholine from lecithin can replace folate and vitamin B12 in some of their functions related to methylation. While it is important to address both of these deficiencies, choline can help prevent the damage before you get to optimal levels of folate and B12. This is also why low MTHFR activity can increase your need for choline if you don’t get enough folate or B12. Low MTHFR activity increases your need for choline by 60-100%.
Reduced liver fat – Phosphatidylcholine supplements can reduce liver fat and prevent fatty liver disease. Phosphatidylcholine is necessary to move fat out of our liver. It also helps digest fat in general. People with NAFLD (non-alcoholic fatty liver disease) will benefit the most.
Lowered blood pressure – This effect was observed in older adults who took CDP-choline but likely applies to phosphatidylcholine from soy lecithin as well since CDP-choline and phosphatidylcholine are almost identical in how they affect the body.
Possible side effects
The side effects below are dose-dependent. The risk for them increases (often linearly but sometimes exponentially) as you increase the dose. Some of the side effects only apply to very high doses.
Excess acetylcholine – Too much acetylcholine can suppress the effects of other neurotransmitters, including dopamine, serotonin, and noradrenaline. This can lead to many symptoms, including irritability, anger, depression, lack of focus, fatigue, ruminating, and more. It is important to note that choline supplements can also increase dopaminergic and serotoninergic neurotransmission.
Allergic reaction – An allergy to this supplement is relatively common.
Nausea – This side effect is most common when people take the supplement on an empty stomach.
Diarrhea – You can usually prevent diarrhea or stomach discomfort by taking this supplement with a meal.
Toxicity – While acute toxicity is extremely rare, taking high amounts of this supplement could lead to chronic toxicity and cause health problems over time. Regularly taking high doses can also cause the body to develop a tolerance to the supplement. To prevent chronic toxicity or the buildup of tolerance, staying below 6 grams in a day is best unless you have a great reason to take more.
Contamination – Contaminated supplements are uncommon in the USA and other well-regulated countries. However, if you wish to buy products from China, India, or other countries without strict regulations, beware that the supplements may be contaminated. Either way, you need to choose the brand you order from wisely. Always read through some reviews for the specific product before you buy it. The FDA (Food and Drug Administration) has the power to regulate dietary supplements but can only do so after they have been on the market for a while. That’s because supplement companies are not obligated to announce to the FDA when releasing a new product. The FDA has to discover the product and test it for potential impurities, which can take a lot of time. During that time, the supplement can be sold on the market even if it’s impure. Also, supplement companies can change their manufacturers without announcing it to the FDA.
Who should not take soy lecithin?
You should probably avoid taking soy lecithin if you:
already consume enough choline and phosphatidylserine from other foods
are allergic to this supplement
experience a severe adverse reaction after taking the supplement
are pregnant or breastfeeding (while it can be safe to take this supplement during pregnancy or breastfeeding, it can put some unnecessary risk to the child)
Who will benefit the most?
You should consider taking the supplement if you:
experience symptoms of choline deficiency, or you know you are deficient based on blood tests
don’t get enough choline from food (the easiest way to find out how much of this nutrient you are getting in your diet is to track your food intake for a while with Cronometer.com)
suffer from schizophrenia
take other nootropics (many of them are unlikely to work well if you don’t get enough choline; some nootropics, such as racetams, significantly increase your need for choline)
have low MTHFR activity (low MTHFR activity increases your need for folate and vitamin B12 but choline can replace folate and vitamin B12 in some of their functions related to methylation; people with low MTHFR activity usually need 60-100% more choline, assuming they also don’t get enough riboflavin)
often engage in cognitively demanding tasks
are on a plant-based diet
are deficient in folate or vitamin B12 (while it is important to address both of these deficiencies, choline can partially help by replacing folate or B12 in some functions)
consume very little protein (less than 0.3 grams/pound of body weight)
have a high budget for supplements and are willing to experiment with a variety of them (assuming you don’t fall into any of the categories that should avoid this supplement, soy lecithin appears relatively safe and is unlikely to do more harm than good for most people)
How much soy lecithin should you take?
The sweet spot dose typically ranges between 2-3 grams daily for most people. This amount should provide most of the benefits without meaningful side effects.
The higher end of this range usually provides slightly more benefits in the short term. If you plan to take this supplement for a longer time (multiple months or years), the lower end is probably a better way to go since it is safer, and you would develop tolerance faster if you were to take higher doses.
The upper safety limit for this supplement is not well-established. To stay on the safe side, don’t take more than the recommended dose unless you have a great reason to do so. Higher amounts may cause problems if you take the supplement for a prolonged period.
Like most other supplements, it is best to cycle soy lecithin and take about two days off weekly to reset your tolerance. That will allow you to keep getting the benefits in the long term.
Best time to take soy lecithin
The main bioactive compounds in soy lecithin are at least partially water-soluble and even if they were fat-soluble, lecithin mostly consists of dietary fat so you don’t have to take it with food to absorb it well.
Whether you take the supplement in the morning or the evening does not make much difference. Both options are fine so feel free to experiment.
Interactions
Ginkgo biloba The two supplements act synergistically for improving memory.
Vitamin B5 Vitamin B5 is needed to make coenzyme A (CoA), which along with choline from lecithin can be used to create the neurotransmitter acetylcholine.
ALCAR and NAC Acetyl-L-Carnitine and N-Acetyl Cysteine both provide the acetyl group that can be used for the synthesis of acetylcholine. In other words, taking one of these makes it easier to produce acetylcholine when paired with choline donors like phosphatidylcholine.
Riboflavin Riboflavin can reduce the fishy smell that may occur when people with a mutation in the FMO3 gene take high doses of phosphatidylcholine.
Piracetam Piracetam potentiates the flow and increases the effects of acetylcholine. It can also deplete choline levels which is why combining racetams with choline donors is a great idea.
Aniracetam Aniracetam leads to higher releases of acetylcholine, increasing your need for this neurotransmitter.
ColuracetamandPramiracetam These two racetams increase the conversion of choline to acetylcholine through the high-affinity choline uptake process (HACU).
Oxiracetam Oxiracetam increases choline acetyltransferase (ChAT), which is used to synthesize acetylcholine
Phenylpiracetam Phenylpiracetam increases the density of acetylcholine receptors.
DHA This combination can be effective for improving memory and cognitive health.
Where to buy soy lecithin?
In most countries, Amazon is the best option for ordering soy lecithin supplements. They offer some very affordable products backed by many positive reviews. Also, you can choose from a wide range of brands without having to search through other markets on the Internet.
Some brands display the dosage per serving instead of per pill or capsule. Therefore, you may accidentally buy something less potent than you intended. Do not fall for this marketing trick.
Soy lecithin vs. sunflower lecithin
Both lecithins share similar chemical compositions and have similar benefits and safety profiles for most people. However, there are some key differences between the two.
Soy lecithin contains approximately 2 times more phosphatidylcholine than sunflower lecithin (21% of dry weight compared to 10.5%). The amount of phosphatidylserine is roughly equal in soy and sunflower lecithin, generally about 1-2%. Soy lecithin also tends to be cheaper.
On the other hand, sunflower lecithin is a safer choice for people with soy allergy, which is more common than an allergy to sunflower seeds.
If you are allergic to one of the lecithins, the other is going to be a better choice. If you are not allergic to either of them, whichever one you choose doesn’t matter much.
FAQ
Like most other supplements, it is best to cycle soy lecithin and take a break from it for about two days per week to reset your tolerance back to baseline. That will keep your body sensitive to the supplement and allow you to keep getting the benefits in the long term.
All of these options are fine. The two most important things to consider are the price and dosing. Powders are almost always the cheapest form. However, you may need a highly accurate scale to dose them correctly (preferably 0.001g). You can get one for as little as $20 from Amazon. Dosing the powders also takes time which can add up over months or years. The disadvantage of capsules is that they are often made of bovine gelatine, which rarely comes from ethical sources.
Yes. Whether you take the supplement in the morning or the evening does not make much difference. Both options are fine so feel free to experiment.
This supplement should not become harmful once it exceeds the expiration date. However, it can lose potency over time. Keep this supplement in a cold, dark, and dry place so it remains as potent for many months or even years.
While acute toxicity is rare, taking very high amounts of this supplement could lead to various problems over time. High doses can also make you develop tolerance much faster than lower doses.
While you could safely take higher doses, there is usually no point in taking more than 6 grams daily. This amount should give you most of the benefits without meaningful side effects.
Soy lecithin contains multiple bioactive components, each of which has a different half-life. For example, phosphatidylserine has a half-life of about 1.5 hours while the half-life of choline from lecithin can be over 3 days. With that said, most of the health effects of lecithin are cumulative, so they mainly happen in the long term rather than acutely. Therefore, the half-life of this supplement isn’t very relevant in practice.
In the long term, you must take the supplement for about 2-4 weeks to begin noticing most of the benefits.
Soy lecithin is very high in dietary fat and can break a fast and reduce its benefits when taken at high doses (5+ grams).
References
Most of the information in this guide is based on scientific research that can be found and verified in the PubMed medical library. We highly encourage you to use the library to verify anything you read in this article. We excluded from consideration studies that are either confounded or have a high conflict of interest.
