Eat fresh meat, fish and eggs. Choose the healthiest animals you can. Grass-fed/pastured is the healthiest but if you can't choose that, do the best you can.
Avoid soy, corn, canola and other vegetable oils. Instead use coconut oil, lard, butter, olive oil.
Avoid grains. White rice is okay in moderation like when you go out for sushi.
Avoid legumes, especially soy.
Get some sunshine.
Move slowly often, sprint once in a while, lift heavy things a few times a week.
Play, have fun, meditate, enjoy life. Spend time in nature if possible, even if that means a city garden or something.
Avoid poisonous things. I would include toxic environments and people in this one.
Female, 5'3", 50, Max squat: 202.5lbs. Max deadlift: 225 x 3.