Collagen side effects
Across 292 first-hand reports, people mentioned a side effect 11 times (about 4 per 100 reports). The most common: fatigue, insomnia, drowsiness. User reports show what people notice — they can't tell you whether Collagen is safe for you.
Reported side effects
fatigue2
insomnia2
drowsiness2
histamine episode1
joint inflammation1
kidney strain1
allergies1
dizziness1
In their own words
“Within hours of consumption my consistent upper back pain is literally gone, but along with it comes dizziness and a feeling of aloofness.”
“I stopped taking collagen powder after years... I used to find I'd get a histmaine episode after taking it sometimes, and get the lethargy.”
“after a couple of weeks of it I get super energised...and my anxiety is much reduced.”
“Started to taking vital proteins collagen powder after workouts. Immediately noticed: very good improvement with libido/erections, more desire to music/life, more active...But… one problem. It sometimes kills my sleep.”
“I've definitely noticed a difference in my skin. But it's slow. I've been taking it about a year now.”
Is Collagen safe? What the research covers
AResearch: Strong9 meta-analyses · 22 randomized trials on PubMed
None of the top reviews we found focus on safety. All research on Collagen.