Hunger Hormone Blue, Green, and Red Light Dose

Chronic sleep deprivation reduces leptin (feeling of fullness) and decreases ghrelin (feeling of hunger).

Red light with only 5 hours of sleep reverses the sleep deprivation effect on the hormones better than getting a full night of 8 hours sleep.

Subjects had better numbers with 5 hours of sleep and 2 hours of red light, than they did with 8 hours of sleep but no red light.

Blue and green light were also superior to no light, but less so than red light.

633 nm, 532 nm, 475 nm, compared to dim light

Four Conditions Compared

• 9 week study
• each subject participated in each condition below
• 5 hours sleep or control of 8 hours of sleep
• upon waking, 120 minutes of one of the conditions below
• subjects wore eye goggles embedded with LEDs
• I calculated the joules total, divide in half to get dose per eye

1. 633 nm, 0.000325 mW/cm^2, 2340 J/cm^2
2. 532 nm, 0.000105 mW/cm^2, 756 J/cm^2
3. 475 nm, 0.000585 mW/cm^2, 4212 J/cm^2
4. 0.5 lux 630 nm dim light (control)

Results