Research

Mixed

A 45-day very-low-calorie ketogenic diet (VLCKD) incorporating whey protein improves muscle strength preservation and yields a healthier gut microbiota profile (increased Bacteroidetes, decreased Firmicutes) compared to vegetable or animal protein sources.

If you are doing a strict low-calorie ketogenic diet, choose whey protein as your primary supplement source. This study suggests it helps preserve muscle strength better than animal proteins (meat/fish/eggs) and promotes a healthier gut bacteria balance. Aim for about 90g of protein daily spread across 5 meals, keeping total calories around 780, and monitor your ketosis via urine strips to ensure you stay in the metabolic state.

ModerateSupportsMEDIUM confidence
VLCKDs based on whey or vegetable protein have a safer profile and result in a healthier microbiota composition than those containing animal proteins. VLCKDs incorporating whey protein are more effective in maintaining muscle performance.
Sabrina Basciani et al. · The Journal of Clinical Endocrinology & Metabolism · 2020

Why this rating

Randomized pilot study with a small sample size (n=48) and short duration (45 days).

Source

Very-Low-Calorie Ketogenic Diets With Whey, Vegetable, or Animal Protein in Patients With Obesity: A Randomized Pilot Study

Sabrina Basciani et al. · The Journal of Clinical Endocrinology & Metabolism · 2020

DOI 10.1210/clinem/dgaa336

rct · n=48Cited 129×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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