Older adults consumed less protein on a vegetarian diet
Protein intake was 0.33 grams per kilogram of body weight per day lower than with an omnivorous diet during 12 weeks of resistance training.
Registered NCT06172725
Limit: Protein intake relied on food records, which can misrepresent actual consumption
Edited by Boris Djordjevic · AgingResearch.News
In a randomized trial, 108 adults aged 55 and older, 58% women, received counseling on a vegetarian diet allowing eggs and dairy or an omnivorous diet. Both groups chose their foods and completed three resistance-training sessions weekly for 12 weeks. They targeted at least 1.2 grams of protein per kilogram of body weight daily.
Both groups met the protein target on average. Muscle mass in the arms and legs rose by 0.38 kilograms with the vegetarian diet and 0.66 kilograms with the omnivorous diet. However, the trial did not establish that the vegetarian diet was no worse within predefined limits for protein intake or muscle mass. Leg press strength and performance on a chair-stand test improved in both groups, with no between-group differences.
Why it matters
For older adults, the study addressed whether a self-selected vegetarian diet could support protein intake, muscle mass and physical function alongside strength training.
Caveats
The range of likely differences in muscle mass included no difference, so the trial did not establish that either diet produced greater gains. The findings concern adults aged 55 and older doing resistance training; the abstract did not report adverse events.
- Resistance training
- Lacto-ovo-vegetarian diet
- Leg press strength
- Chair-stand test
- Handgrip strength
- Humans
The paper
Amsterdam University of Applied Sciences; Radboud University Nijmegen
The American Journal of Clinical Nutrition, Sep 22, 2026, Open access