Midlife timed feeding linked to muscle insulin response in mice
In a 12-week experiment in male mice, restricting daily eating times was linked to preserved lean mass and muscle insulin responsiveness in midlife.
Limit: Membrane proteins were not directly manipulated to measure their contribution to muscle insulin responses
Edited by Boris Djordjevic · AgingResearch.News
Male C57BL/6J mice underwent experiments comparing 12 weeks of time-restricted feeding, which limits eating to a daily window, with alternate-day fasting. The interventions began at 3, 12, 15 or 18 months of age.
The effects depended strongly on age. Midlife time-restricted feeding preserved lean mass and improved glucose tolerance, the ability to handle sugar in the blood. It also increased sugar uptake in isolated muscle stimulated with insulin, a hormone that regulates blood sugar. Alternate-day fasting produced broader metabolic changes but was associated with lean-tissue loss when started later in life. Aging muscle had lower levels of a protein assembly at the muscle-cell membrane involved in insulin signaling. Midlife time-restricted feeding was associated with higher levels of these proteins.
Why it matters
Age-related muscle loss partly reflects a reduced ability to activate protein production in response to nutrients and hormones. This work addresses when dietary timing might help maintain muscle during aging.
Caveats
These animal experiments did not establish that the membrane-protein differences caused the muscle effects. The findings concern male mice, not females or people.
- Time-restricted feeding
- Alternate-day fasting
- Insulin/IGF-1 signaling
- PI3K–AKT signaling
- Primary sarcopenia
- Mice
Time-restricted feeding is part of Bryan Johnson's Blueprint
The paper
Technion – Israel Institute of Technology
American Journal of Physiology Cell Physiology, Oct 9, 2026
