Ideas emerging from the aethers. Been learning bits about evolutionary psychology.
As well as leptin and ghrelin, other hormones seem to affect hunger. e.g. women need more energy intake during certain times in a cycle. (re Lyle McDonald.)
PMS is worse if you’re not eating enough.
Running and exercise help with stress and burning off our fight/flight instincts when most of us have desk or indoor jobs that can be very stressful. But too much intense exercise increases stress (adrenaline and cortisol).
I’ve suspected for a while that testosterone compels men to continually compete and overdo it when they exercise. It’s certainly pretty bad for women comparing ourselves to others in the gene pool. And social media and technology’s effects on top causing us to want to look more awesome than the next person.
I have more I could say about this all leading to injuries, and un-sustainability in fitness.
Dopamine and serotonin can also be nice happy comfortable influences that make competitiveness less important and make us want to be happy just being with our tribe around our campfire safe from wild animals.
I guess these hormones can also be part of the reason people want to stick to a diet their peers prefer.
Zenmode 
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