I'm thinking primarily about food here, but I'd include anything about behavior, activity, routine, etc if you think that there's a case for it.
In my case I'm pretty sure that spicy food is somehow good for you. Not to excess, but I feel like regular consumption of capsaicin rich foods is good for the digestive tract somehow. And given the strong relationship between the nervous system of the stomach and the brain, it's probably got some correlative events in the brain.
Spicy foods are good for you but I have never seen a good study on why that is. I saw one study that capsacian eats arterial plauge and another that it aids in promoting health bone marrow. Sadly I cannot find those right now. I believe that sugar is bad for you. Corn sugars are even worse for your health. The problem with proving that is the insane amounts of woo woo around health and dieting claims. For me anyway, if I eat sugary foods, I feel like crap for about 24 hours. I've been sleeping better and more functional since I gave up the sweets, pastas and breads.
Maybe taking a bath each third day. Bathing daily is not natural, maybe harmless but bath bit less is more healthy.