My doc said 10am was the peak level and that was about the time of my test.You are correct. But I wasn't aware it was by that much. Glad my blood sample was taken at 7:00am. @mandown
Yes, testosterone levels vary throughout the day, with the highest levels in the morning and the lowest levels in the evening:
Men
Testosterone levels in men are usually highest between 7 and 10 AM after a night's rest. Levels then decrease during the day, reaching their lowest point around 8 PM. Testosterone levels in men under 40 can fluctuate significantly, with variations of up to 35% between the morning and mid- to late afternoon. This variation decreases with age, dropping to around 10% in men in their 70s.