Recent Cell paper "Host-Microbe-Drug-Nutrient Screen Identifies Bacterial Effectors of Metformin Therapy" screened the nutrient that will affect metformin therapy. They screened 337 different nutrients and found that sugar and carbohydrates will compromise the anti-aging effect of metformin.
https://www-cell-com.ezp-prod1.hul.harv ... 0891-8.pdf
Healthy Aging News and Research ⇒ Extra Sugar intake will compromise the anti-aging effect of Metformin
Extra Sugar intake will compromise the anti-aging effect of Metformin
Ph.D. student at Harvard Medical School, doing research on aging