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Optimum Nutrition Gold Standard 100% Whey vs Yu Sleep

The published reviews of Optimum Nutrition Gold Standard 100% Whey and Yu Sleep, lined up: the five scores, what one serving delivers against the studied dose, the real cost per serving and what each label leaves out. Figures as of 22 September 2026.

The short answer

Optimum Nutrition Gold Standard 100% Whey scores 7.0/10 against Yu Sleep's 1.8. The widest gap is safety and tolerability: 8 for Optimum Nutrition Gold Standard 100% Whey, 1 for Yu Sleep.

Pick Optimum Nutrition Gold Standard 100% Whey if…

  • tolerability and a well-characterised safety record come first
  • you want a serving that matches the amount used in research
  • you want the stronger evidence behind what it is sold to do

Pick Yu Sleep if…

It does not lead on any criterion we score. Read its review for the case in its favour.

Criterion by criterion

The five criteria every review is scored on, published on the grading page. The overall score is their average.

Evidence for the marketed claim

How strong the research is for what the product is actually sold to do — not for the ingredient in general.

Optimum Nutrition Gold Standard 100% Whey8/10Leads
Yu Sleep3/10

Dose against the studied amount

Whether one serving delivers the amount used in the research behind the claim.

Optimum Nutrition Gold Standard 100% Whey8/10Leads
Yu Sleep2/10

Label transparency

Whether the Supplement Facts panel is published in readable text and every active amount is disclosed.

Optimum Nutrition Gold Standard 100% Whey6/10Leads
Yu Sleep1/10

Value against the generic equivalent

Cost per gram or per dose of the active ingredient, compared with the plainest version of the same thing.

Optimum Nutrition Gold Standard 100% Whey5/10Leads
Yu Sleep2/10

Safety and tolerability

Known risks and interactions, how well characterised they are, and whether the label warns about them.

Optimum Nutrition Gold Standard 100% Whey8/10Leads
Yu Sleep1/10

Dose against the studied amount

What one labelled serving delivers, placed against the range on each ingredient’s evidence page. Where a label gives no figure, there is nothing to place, and that is the finding.

Whey protein blendEvidence A

Where muscle protein synthesis maxes out: 20–25 g a dose

  • Optimum Nutrition Gold Standard 100% Whey24 g protein per 30 g servingIn range
  • Yu SleepNot in the formula

L-theanineEvidence B

Studied dose: 100–200 mg a dose

  • Optimum Nutrition Gold Standard 100% WheyNot in the formula
  • Yu SleepNot disclosedUndisclosed

GABAEvidence D

Trial range: 100–300 mg a dose

  • Optimum Nutrition Gold Standard 100% WheyNot in the formula
  • Yu SleepNot disclosedUndisclosed

What it actually costs

Price divided by labelled servings, from a dated listing. A serving is whatever the label calls one, which is why the studied-dose row matters more than the headline figure.

  • Optimum Nutrition Gold Standard 100% Whey£39.99–£50.00 across seven UK retailers, checked 22 September 2026. No per-serving figure: servings not recorded.
  • Yu Sleep$138 for a two-month package, down to $49 a month on the six-month. No per-serving figure: servings not recorded.

Label checks

What each label discloses, and what it leaves out. Read from the reviews, not from the marketing.

Optimum Nutrition Gold Standard 100% Whey

  • 2 of 3 listed ingredients have no stated amount
  • No third-party certification

Yu Sleep

  • 6 of 7 listed ingredients have no stated amount
  • No third-party certification
  • Scored 1/10 for safety and tolerability

How this comparison is built

  • Scores are the ones already published in each review. Nothing is re-scored for the comparison, and a product leads a criterion only when it outscores the rest.
  • Doses are read from the label rows in each review and placed against the studied range on the matching ingredient page. A figure that is not printed is never estimated.
  • Costs use a dated retailer price divided by labelled servings. Prices in different currencies are never ranked against each other.
  • Only products in the same category, or ones a review names as an alternative, can be compared. Commission never changes what appears here.

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