The 7-hour casein window: does overnight protein synthesis actually peak?
A meta-analysis of 14 nighttime feeding studies — and the practical takeaway for lifters who train after 7 p.m.
Guide
Slow-release protein, decoded with evidence — not hype.
100 Casein is the independent research desk for casein protein and overnight sports nutrition. We translate peer-reviewed findings into practical guidance so you can recover smarter, sleep deeper, and train harder tomorrow.
By the numbers
Trusted by lifters, validated by literature
Every claim we publish is anchored to primary research — from 24-hour amino-acid tracer studies to double-blind recovery trials. No sponsored rankings, no affiliate fluff.
218
Peer-reviewed studies reviewed in 2024
7h
Sustained leucinemia vs. 2h with whey
63
Products independently lab-tested
0
Sponsored placements — full stop
Featured this month
The reads our readers opened first
Long-form breakdowns, comparison reports, and protocol deep-dives from our research team.
Comparison
2025 Casein Rankings: 14 tubs, one independent lab, zero brand dollars
Every product paid its own way through our lab. We tested purity, leucine content, and mixability. Here are the results.
Deep Dive
Micellar vs. hydrolyzed vs. calcium caseinate: which actually lasts 7 hours?
The digestion kinetics of every major casein format, plotted against real blood-amino curves — not marketing claims.
The Casein Buyer's Checklist
Six things to verify before you open your wallet
A free excerpt from our flagship supplement guide. Run any tub through this filter in under three minutes.
Verify the casein type
Micellar is the slow-release gold standard. Calcium caseinate is fine. "Casein blend" without ratios is a red flag.
Check the protein-per-serving math
A 30 g scoop should deliver at least 24 g of actual protein. Anything below 80% efficiency is heavily diluted.
Scan for third-party testing
NSF, Informed Sport, or Labdoor seals mean the label is honest. If none exist, treat the marketing as fiction.
Audit the sugar and fat
Premium casein clocks 1–3 g sugar and under 2 g fat. If it tastes like a milkshake, it probably is one.
Confirm the leucine threshold
Look for at least 2.5 g leucine per serving — the minimum dose that reliably triggers muscle protein synthesis.
Price per gram of protein
The cheapest tub rarely wins. Calculate cost against actual delivered protein, not scoop weight.
Why readers stay
The editorial standard behind every article
We do the slow work so your decisions don't have to be slow. Here's what makes our research desk different.
Primary sources only
Every claim links to PubMed, the journal of record, or a raw dataset — never a press release.
Independent lab data
We batch-test products quarterly. Brands pay nothing — and cannot edit, veto, or preview results.
Updated, not abandoned
Articles carry a "last reviewed" stamp and a changelog. Sports nutrition evolves — our archives do too.
Practitioner review
Every guide is reviewed by a registered dietitian or sports physiologist before it ships to readers.
How we work
From PubMed search to published guide
Our research workflow is the same for a 500-word product note or a 4,000-word protocol. Here's the path every article travels.
1
Question framing
Define the exact decision a reader is trying to make — and the evidence threshold needed to answer it.
2
Literature sweep
Search PubMed, Cochrane, and sport-nutrition registries. Filter for sample size, population, and methodology.
3
Independent verification
Where product claims are involved, our lab re-runs amino-acid profiling and heavy-metal panels from scratch.
4
Practitioner review
A registered dietitian or sports physiologist challenges every recommendation before publication.
Reader voices
What our community says
Coaches, competitive lifters, and curious readers weigh in on how 100 Casein changed their approach to overnight recovery.
★ ★ ★ ★ ★
"I dropped 40 grams of cheap whey and switched to a micellar casein from the index. Eight weeks later my sleep tracker shows +18% deep sleep on training nights."
★ ★ ★ ★ ★
"The Buyer's Checklist saved me from a $70 tub of 'casein' that was 38% whey. I run every supplement through it now. Total no-brainer resource."
★ ★ ★ ★ ★
"I recommend 100 Casein to every client running an evening PPL. The casein-vs-whey primer alone has reshaped my overnight nutrition plans."
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