Vitamin C: A standard dose is often 500mg taken once or twice daily
[PDF] springer.com Ko, Nai-Yu, et al
This compound is supplied exclusively for research purposes and is not approved as a medicine, supplement, or therapeutic product in Thailand or elsewhere
10.1007/s00204-016-1781-0 Arch
Some researchers have studied vitamin B12 to find out if it can increase energy and endurance during exercise, but the results are inconclusive
Signs and symptoms of vitamin B12 deficiency can include fatigue, pale skin, headaches, shortness of breath, fast heartbeat, gastrointestinal issues, mouth inflammation, paresthesias (abnormal sensations), decreased cognitive ability, depression, muscle weakness, imbalance and incoordination, vision problems, and erectile dysfunction