Glycine sits in skin, tendons and bone, which is exactly the part hardly anyone bites into today. A fillet holds little of it, gelatine a lot. We worked out how much exactly.
A good nine sheets of gelatine
Gelatine is the richest source of glycine you can buy. 100 grams of gelatine powder contain 19 grams of glycine. For the 3 grams used in the sleep studies, you need just under 16 grams of gelatine.
One sheet weighs about 1.7 grams; a pack of 6 sheets weighs 10 grams. For 3 grams of glycine, that is a good nine sheets. According to the maker, one pack sets half a litre of dessert. So you would need one and a half packs, every evening.
The other classic source is broth made from bones and skin. It simmers for hours, and how much glycine ends up in it varies widely from pot to pot. Hardly anyone makes that every evening.
How much glycine is in food
All values are per 100 grams, weighed raw. The right-hand column shows how much you would have to eat to reach 3 grams of glycine.
| Food | Glycine per 100 g | Amount for 3 g glycine |
|---|---|---|
| Gelatine, powder | 19.0 g | 16 g, a good nine sheets |
| Beef tenderloin, lean | 1.15 g | 260 g |
| Tofu, firm | 0.384 g | 780 g |
Raw values per 100 g from USDA FoodData Central, retrieved on 18.10.2026. Amounts rounded: below 50 g to 1 g, above to 10 g.
260 grams of beef tenderloin is a decent steak. Hardly anyone eats 780 grams of tofu in one evening.
What is missing from today's plate
Skin, cartilage and tendons used to go into the pot. Today, fillet and breast end up on the plate and the connective tissue usually stays out. That removes the part of the animal where most of the glycine sits: in collagen, about every third building block is glycine.
If you eat vegetarian or vegan, soybeans, pumpkin seeds and pulses bring you to just under 2 grams per 100 grams, weighed dry. For 3 grams of glycine, that would be 160 grams of soybeans or 300 grams of lentils a day.
The body does not depend on food alone for this. It makes part of it itself.
And magnesium bisglycinate?
Magnesium bisglycinate is on the label of many magnesium supplements. It is magnesium bound to two glycine building blocks. By weight, about 14 percent of it is magnesium.
To get 3 grams of glycine from it, you would need 3.4 grams of bisglycinate. That contains 486 milligrams of magnesium. In Switzerland, a food supplement may supply at most 375 milligrams of magnesium a day, and from 250 milligrams it must carry a note that magnesium can have a laxative effect.
The other way round, a usual daily amount of 300 milligrams of magnesium as bisglycinate brings about 1.9 grams of glycine with it. The calculation uses molar masses: one mole of bisglycinate weighs 172.4 grams, contains 24.3 grams of magnesium and yields two moles of glycine at 75.1 grams each.
So magnesium bisglycinate is a magnesium supplement, and glycine is the carrier. If you want 3 grams of glycine, take glycine.
Three capsules instead of nine sheets
One PureGlycin capsule contains 1 gram of glycine. Three capsules with a glass of water give you the amount from the sleep studies. No cooking, no powder, no weighing, nothing sweet on the tongue. The shell is made of cellulose and the capsules are vegan.
When best to take them is explained in our guide to taking glycine.
Sources
- U.S. Department of Agriculture: FoodData Central, SR Legacy database. Entries 169599 (gelatine), 174736 (beef tenderloin), 172448 (tofu), 174270 (soybeans), 170556 (pumpkin seeds), 172420 (lentils). To the database
- Dr. Oetker white sheet gelatine, pack details: 6 sheets, 10 grams, for 500 ml of liquid. To the product
- Alcock RD, Shaw GC, Burke LM: Bone broth unlikely to provide reliable concentrations of collagen precursors compared with supplemental sources of collagen used in collagen research. International Journal of Sport Nutrition and Exercise Metabolism, 2019. To the study
- Swiss Ordinance on Food Supplements (VNem), SR 817.022.14, as of 1 February 2024, Annex 1 (magnesium, glycine) and Annex 2 (magnesium bisglycinate). To the ordinance
- Wikipedia: Gelatin, amino acids in collagen. To the article