Research

Hormonal

Chronic antioxidant supplementation (specifically Vitamin C and E) interferes with skeletal muscle adaptation to exercise training by attenuating improvements in insulin sensitivity, mitochondrial biogenesis, and antioxidant capacity.

If you are training regularly, avoid taking high-dose Vitamin C and E supplements. They block the molecular signals your body needs to build mitochondria and improve insulin sensitivity. Let the exercise stress do its job.

GoodRefutesHIGH confidence
There is building evidence that antioxidant supplementation can attenuate endurance training-induced and ROS/RNS-mediated enhancements in antioxidant capacity, mitochondrial biogenesis, cellular defence mechanisms and insulin sensitivity.
Troy L. Merry et al. · The Journal of Physiology · 2015

Why this rating

Based on a review of multiple human and rodent studies, though results vary by protocol.

Source

Do antioxidant supplements interfere with skeletal muscle adaptation to exercise training?

Troy L. Merry et al. · The Journal of Physiology · 2015

DOI 10.1113/jp270654

narrative_reviewCited 310×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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