According to a small-scale study, thin people don't necessarily eat better or exercise more than others  They just get up early and get more sun for a while  The effect of dawn on body mass index is about 20%  The earlier they get up and get in the sun, the lower their body mass index
On the contrary, researchers suggest that if they want to lose weight, they just need to get up early and get in the sun for a while
Farmers in some areas get up early every day and work hard in the dark. They have always been very thin