Short courses of collagen probably understate what a full one does
The trials ran 4 to 16 weeks at daily amounts spanning 0.4g to 12g, and no recommended figure falls out of them. One 160-person trial used 10g a day.
What the study found
The longer people took collagen, the larger the effect
The trials ran 4 to 16 weeks, and the shortest of them likely understate what a full course does. Daily amounts spanned thirtyfold, 0.4g to 12g, and no recommended figure falls out of them. One 160-person trial at 10g a day moved osteoarthritis scores from 53.7 to 33.8 in eight weeks.
The caveat · One brand, no independent repeat
The joint trial tested one branded product, and two of its authors work for the manufacturer and for the contract firm that ran it, so an independent repeat is still missing. Several outcomes in the largest synthesis, skin roughness among them, came out flat.