Healthnews24South Africa's supplement answer desk

Does whey protein cause acne?

Healthnews24 editorial deskUpdated 2 min read
Answer first

The evidence that whey causes acne is mixed and weak, and there are no South African trials. Observational studies link dairy to acne (pooled odds ratio 1.25), and case reports describe flares in young men, but the one randomised trial we found (49 men, 30 g a day for six months) showed no significant worsening. Try a four- to eight-week break, and see a dermatologist.

  • Juhl et al. (2018): pooled odds ratio of 1.25 for acne with any dairy in 14 observational studies and 78,529 people aged 7–30.
  • Sompochpruetikul et al. (2024): 30 g a day of whey for six months did not significantly increase acne lesions in 49 young men.
  • Duiven et al. (2021): 38% of 66 muscle-gain and fat-loss supplements contained undeclared doping substances, which can cause acne.
  • Evidence level: weak; individual responses vary.

Does whey protein cause acne?

Possibly in some people, but the evidence does not show that whey causes acne in most. We rate it weak: the data are mostly observational or small trials.

What does the research show?

  • Dairy overall: a 2018 meta-analysis (Juhl et al.) pooled 14 observational studies and 78,529 children, adolescents and young adults aged 7–30. Any dairy had an odds ratio of 1.25 (95% CI 1.15–1.36), milk 1.28, yoghurt 1.36 and cheese a borderline 1.22. The authors warn about heterogeneity, publication bias and confounding, so this shows an association, not proof of cause.
  • Whey specifically: case reports and case series describe acne flares in young men using whey, but they cannot show cause. A 2024 randomised noninferiority trial (Sompochpruetikul et al., 49 men with mild to moderate acne, mean age about 20) gave 30 g of whey daily for six months and found no significant increase in lesions or severity against a non-whey control. The confidence intervals were wide, so the trial cannot exclude a modest effect in either direction.
  • Proposed mechanism: milk proteins may raise insulin and IGF-1 signalling, which influences oil glands. This is a hypothesis rather than a result in whey-supplement trials.

What else could be behind the spots?

Whey is rarely the only change. Mass gainers add sugar, creatine and pre-workouts get started in the same weeks, sleep and stress shift, and training raises sweat and friction from kit. Some "muscle" products contain undeclared steroids or prohormones, which cause acne: a 2021 Dutch study found 38% of 66 muscle-gain and fat-loss supplements contained undeclared doping substances (see are prohormones and steroids in supplements illegal). If acne arrives with a new multi-ingredient product, stop it and see a doctor.

What can you try?

  1. Keep a photo diary for two weeks, then stop whey for four to eight weeks and compare.
  2. Reintroduce a single-ingredient isolate such as USN Isozero 805 g (about R899) or NPL 100% Isolate; isolate has less lactose and fewer carbohydrates, but it is the same milk protein, so it may not help.
  3. Try a plant protein (FtN Pea Protein Isolate R148–R185) if dairy is the trigger. See best lactose-free protein.
  4. Check sweeteners and sugar in your tub; see why whey bloats you.
  5. Get food-first protein if you are a school athlete (supplements under 18).

When should you see a dermatologist?

If acne is painful, scarring, spreading to the back or chest, or does not improve after eight weeks, see a dermatologist or doctor; they can treat it whether or not whey is involved. Tell them about every supplement you take. Browse the best whey isolate page for single-ingredient options.

Products mentioned, with dated prices

ProductSizePriceR per 30 g proteinR per 100 g powderSweeteners
USN Isozero Whey Protein Isolate (805 g)805 gR899-R909.99USN shop (za.usn.global), Oct 2026R38.53R111.68not stated
NPL 100% Whey Protein Isolate (700 g)700 gR900NPL shop (npl.za.com), Oct 2026R48.46R128.57sucralose
Faithful to Nature (FtN) Pea Protein Isolate Powder (650 g)650 gR148-R185Faithful to Nature, Oct 2026R11.38R28.46none

Compare the options

Sources

  1. Juhl et al. 2018, Dairy intake and acne vulgaris: systematic review and meta-analysis of 78,529 children, adolescents and young adults (Nutrients 10(8):1049)
  2. Sompochpruetikul et al. 2024, whey protein supplementation and acne in young men: randomised noninferiority trial (J Dermatol 51(7):1022) — news summary
  3. Duiven et al. 2021, Undeclared doping substances are highly prevalent in commercial sports nutrition supplements (J Sports Sci Med 20:328)

Educational information only, not medical advice. Speak to a doctor, pharmacist or registered dietitian before using supplements if you are pregnant or breastfeeding, under 18, taking medication, or living with kidney, liver or heart disease.

Cite this page: Healthnews24, “Does whey protein cause acne?”, updated 27 October 2026, https://www.healthnews24.co.za/answers/does-whey-protein-cause-acne/. Plain-text version: /answers/does-whey-protein-cause-acne.md