There is evidence that the amount of carbohydrate consumption can increase your blood serum levels of tryptophan. Tryptophan increases blood serotonin which makes you feel good and soothes you for good sleep. Source. But Tryptophan is also a precursor to melatonin. The key part about melatonin is the daily cycle which is mainly affected by daylight, but is also somewhat affected by diet. This study I found said "Thus, the health benefits of diet-driven melatonin boosts seem not to be the product of any single food or nutrients present in the diet." This would seem to contradict the book The Adrenal Reset Diet which I have read said that you can cycle your carb intake to help control melatonin levels. This book along with Dr Christianson's personal experience gave convincing evidence that this might work. The book did have some woo woo stuff which I skipped over, but it also had a lot of very good information for people out there that get very stressed on a consistent basis.