Three capsules, a glass of water, half an hour to an hour before bed. Taking glycine is that simple, and that is exactly how it was done in the sleep studies.
When
30 to 60 minutes before going to bed. That is what participants did in all three sleep studies. With or without food, either is fine.
What an evening in the study looked like
The three sleep studies followed a similar pattern. This is what an evening in the laboratory looked like:
- One hour before bed: 3 grams of glycine or a placebo. Participants did not know which they were given.
- Lights out: in the laboratory study, electrodes recorded brain waves, eye movements and muscle tension.
- The night: with glycine, participants fell asleep faster and reached deep sleep sooner. Otherwise the sleep stages were spread as in the placebo night.
- The morning: they described themselves as more awake and less tired. Those who had slept too little reacted faster in the reaction test.
What might be behind it probably has to do with body temperature.
How much, and does more help more?
3 grams, so three capsules. All three sleep studies used this amount, and all the results come from it. That is why we stick to it.
Swiss regulations allow up to 5 grams of glycine a day; at 3 grams, our daily dose is well below that. The stated recommended daily dose must not be exceeded.
How long in a row, and does the body get used to it?
Glycine is a building block your body makes and uses every day anyway. There are no signs that the body gets used to it. You can take it every evening and pause at any time.
Side effects and risks
No adverse effects were reported in the sleep studies with 3 grams. In a small study, twelve people even took 9 grams during the day, also without adverse effects. None of these studies was designed specifically to look for side effects, and the groups were small.
Only very high amounts, as tested in medicine, do not suit everyone. In a study with up to 60 grams a day, some participants reported nausea and vomiting. That is twenty times our daily dose.
If you take medication, ask your doctor first. PureGlycin is not intended for pregnant or breastfeeding women or for children.
Capsule or powder
Glycine is also sold as a powder. It tastes slightly sweet and has to be weighed out every evening. Three capsules are exactly 3 grams, with no scales and no taste.
And if you would rather try it through food: 3 grams of glycine take a good nine sheets of gelatine.
Sources
- Yamadera W, Inagawa K, Chiba S, Bannai M, Takahashi M, Nakayama K: Glycine ingestion improves subjective sleep quality in human volunteers, correlating with polysomnographic changes. Sleep and Biological Rhythms, 2007. To the study
- Inagawa K et al.: Subjective effects of glycine ingestion before bedtime on sleep quality. Sleep and Biological Rhythms, 2006. To the study
- Bannai M, Kawai N, Ono K, Nakahara K, Murakami N: The effects of glycine on subjective daytime performance in partially sleep-restricted healthy volunteers. Frontiers in Neurology, 2012. To the study
- Bannai M, Kawai N: New therapeutic strategy for amino acid medicine: glycine improves the quality of sleep. Journal of Pharmacological Sciences, 2012 (includes the study with 9 grams during the day). To the study
- Strzelecki D, Rabe-Jabłońska J: study of glycine added to antipsychotics, up to 60 grams a day. Psychiatria Polska, 2011 (in Polish, English abstract). To the study
- Swiss Ordinance on Food Supplements (VNem), SR 817.022.14, Annex 1 (glycine, 5 grams). To the ordinance