when to drink it, and whether the time of day really matters

This question comes up constantly and it carries more anxiety than it deserves. Morning or night. With food or without. Before or after the gym.

There are exactly two timing windows with real evidence attached. Everything else is a habit question, and the habit question is the one that actually decides your outcome.

window one, before activity

This is the strongest timing finding in the field. Shaw and colleagues, in the American Journal of Clinical Nutrition in 2017, gave participants gelatin with vitamin C one hour before short bouts of jump rope, and measured markers of collagen synthesis in blood afterwards.

The higher dose group roughly doubled a marker of collagen synthesis compared with placebo.

The reasoning is that tendon and ligament have famously poor blood supply, so you want circulating amino acids at peak when the loading happens. An hour ahead lines those two things up.

If your interest is joints and tendons, that is the window. About an hour before you move.

window two, before bed

This one is not about collagen absorption. It is about glycine.

Collagen is roughly a third glycine, which is a far higher proportion than almost any other protein you eat. Yamadera and colleagues found that three grams of glycine before bed improved subjective sleep quality and next day alertness in people with poor sleep. Other work has linked glycine to a small drop in core body temperature, which is part of how the body initiates sleep.

Twenty grams of collagen protein carries a meaningful amount of glycine on its own. That is why an evening can is not a strange idea, and it is when I drink mine.

what does not matter as much as people think

Empty stomach versus with food. There is no good evidence that a meal blocks collagen peptide absorption, and Iwai's work found peptides circulating regardless.

Coffee. It does not destroy collagen. Heat can denature protein but denaturing hydrolysed peptides does not undo the hydrolysis. The only real caution is that very hot liquid degrades vitamin C, which does matter if you are relying on your collagen source for that cofactor. Ours is cold, so it is a non issue.

Splitting the dose. Trials generally used one daily serving and found effects. One is fine.

the thing that actually decides it

Consistency. Every study I have written about on this blog measured daily intake over months. The best time to drink it is the time you will still be drinking it in twelve weeks.

For me that turned out to be evening, cold, out of the fridge, because it slotted into something I was doing anyway. For you it might be nine in the morning. Attach it to an existing habit rather than to an intention, and the timing question mostly solves itself.

the research i leaned on

• Shaw G, Lee-Barthel A, Ross ML, Wang B, Baar K. Vitamin C-enriched gelatin supplementation before intermittent activity augments collagen synthesis. American Journal of Clinical Nutrition. 2017;105(1):136-143.
• Yamadera W, Inagawa K, Chiba S, et al. Glycine ingestion improves subjective sleep quality in human volunteers, correlating with polysomnographic changes. Sleep and Biological Rhythms. 2007;5(2):126-131.
• Iwai K, Hasegawa T, Taguchi Y, et al. Identification of food-derived collagen peptides in human blood after oral ingestion of gelatin hydrolysates. Journal of Agricultural and Food Chemistry. 2005;53(16):6531-6536.

LÉS is a beverage, not medicine, and nothing here is medical advice.