Optimizing mood and metabolism requires personalized adjustments to light exposure due to variations in melatonin receptors and individual factors.

“There is no one size fits all prescription because there's a range of melatonin receptors, there are a range of everything from metabolic types to genetic histories, family histories, et cetera. There is no one size fits all prescription but by understanding that light and extended day length inhibit melatonin and melatonin tends to be associated with a more depressed or reduced functioning of these kinds of activity driving and mood elevating signals, and understanding that you have some control over melatonin by way of light, including sunlight but also artificial light, and that should empower you I believe, to make the adjustments that if you're feeling low you might ask, how much light am I getting? What am I getting that light?”