Lecithin: what it's used for, sunflower vs soya lecithin, and what we know about phosphatidylserine

What lecithin is

Lecithin isn’t a single substance. It’s a mix of fat-like compounds called phospholipids, and the main one is phosphatidylcholine. That’s what supplies choline, a nutrient your body needs for cell membranes, the liver and the nervous system.

Commercial lecithin is made by purifying phospholipids, mostly from soya and sunflower. In food it works as an emulsifier (labelled E322): it helps fat and water mix in gravies, salad dressings and margarine.

On iHerb, lecithin comes in three main forms:

• granules – stirred into yoghurt, porridge or smoothies;
• softgels – convenient, but a 5 g dose usually means several of them;
• liquid lecithin – mostly for cooking.

Lecithin benefits: what the evidence says

Lecithin is marketed for the brain, liver, heart and skin. The sources support far less:

Not sure where to start? Our short vitamin check suggests which supplements make sense for you.

Sunflower lecithin vs soya lecithin

Both are essentially the same thing: a mix of phospholipids rich in phosphatidylcholine. What differs is the source.

A word on allergy. Allergy UK explains that lecithin is a fat with very little soya protein, so most people with soya allergy can tolerate it. Even so, soya lecithin isn’t on the exemption list under UK and EU allergen rules, so soya must be declared on the label. If your allergy is severe, choose sunflower lecithin and check with your allergy clinic.

Lecithin and choline: how much you need

Your body makes some choline, but not enough. Intake guidance:

• EFSA (2016): an adequate intake of 400 mg a day for adults, 480 mg in pregnancy and 520 mg when breastfeeding.
• US (NIH ODS): 550 mg for men and 425 mg for women, with an upper limit of 3.5 g a day for adults.

Beef liver tops the list (356 mg per 85 g), followed by eggs (147 mg in one large egg), beef (117 mg per 85 g) and roasted soya beans (107 mg per half cup). Chicken and cod give about 70 mg a portion.

See how these foods compare with the daily intake:

Lecithin is an imprecise way to top up choline, because the label usually gives the weight of lecithin, not choline. If you need a set amount of choline, a choline supplement with the dose in milligrams is easier. NIH ODS notes that pregnancy supplements usually contain little or no choline, which we cover in pregnancy vitamins.

Very high choline intakes can cause a fishy body odour, sweating, vomiting and low blood pressure.

Phosphatidylserine and memory

Phosphatidylserine is another phospholipid, often sold next to lecithin for memory. What’s known:

• The US FDA in 2003 allowed only a qualified claim that it may reduce the risk of cognitive dysfunction and dementia in older people. Its own wording says the research is very limited and preliminary.
• A 2003 Cochrane review, cited by NIH ODS, found no clear benefit of lecithin in Alzheimer’s disease or Parkinson’s-related dementia.
• A 2015 review of 13 studies found no clear memory benefit from choline supplements in healthy adults.

If your memory has got noticeably or suddenly worse, see your GP rather than buying a supplement. Other products sold for memory are reviewed in brain and memory supplements, including ginkgo biloba.

Sunflower lecithin for blocked milk ducts

The Academy of Breastfeeding Medicine (ABM) protocol from 2022 says sunflower or soya lecithin, 5–10 g a day by mouth, may be taken to reduce inflammation in the ducts. It’s graded C, which means the evidence is limited.

Lecithin doesn’t appear on the NHS page on mastitis, which sticks to the basics:

1. Keep breastfeeding whenever your baby wants, and don’t express more milk than your baby needs.
2. Ask a midwife, health visitor or breastfeeding specialist to check positioning and attachment.
3. Use a cold compress for 10 minutes every hour, rest, and take paracetamol or ibuprofen for pain or a high temperature.
4. Keep any pressure on the breast gentle. The ABM protocol also warns that deep massage can make inflammation worse.

See a GP if you’re no better 12–24 hours after starting these steps. You may need antibiotics, and lecithin doesn’t replace them. The National Breastfeeding Helpline (0300 100 0212) is open 24 hours a day.

Lecithin and cholesterol

Lecithin is often sold for heart health. Yet in a double-blind trial, 20 g of soya lecithin a day for 4 weeks didn’t change total cholesterol, LDL or triglycerides in men with raised blood fats. The study was small (20 men), and a 2024 narrative review also calls the findings conflicting.

Diet, activity and, where needed, medicines are what lower cholesterol. For fats and heart health, read how to choose omega-3.

Side effects and who should be careful

Lecithin in food amounts is usually well tolerated. Reviews occasionally report:

• diarrhoea;
• nausea;
• at very high choline intakes, a fishy body odour and sweating.

Take extra care:

• with a soya allergy, choose sunflower lecithin;
• in pregnancy or while breastfeeding, talk to your midwife or GP about supplements;
• for children, doses depend on age and weight, so only after advice from a GP or pharmacist.

We found no well-documented drug interactions for lecithin in reliable sources. If you take several supplements, check our vitamin compatibility chart.

How to choose lecithin on iHerb

1. Decide why you want it: blocked ducts, choline, or “just in case”. In the last case, you probably don’t need it.
2. If you avoid soya, choose sunflower lecithin labelled soy-free.
3. Work out the dose: grams per serving and how many softgels make 5 g.
4. For choline, choose a choline supplement with the dose in milligrams, not lecithin.
5. Our guide to reading supplement labels shows where to find the dose and source.