The body requires fasting perios in order to survive and stay healthy.

According to Scientists at ETH Zurich: a large breakfast followed by a moderate lunch and lastly a small dinner should be eaten on a day to day basis. this should not involve snacks inbetween to allow the body to starve itself ready for the next meal.

The principal which underlies this theory is down to a transcription factor Foxa2. Foxa2 is controlled by the amount of insulin circulating within the blood stream. It is found in liver cells and in two important neuronal populations within the hypothalamus.

Foxa2 triggers the production of MCH and orexin, these two hormones cause an organism to be more alert and more active in order to find food and survive.

When food is in ingested, levels of insulin are lower and Foxa2 transcription in the hypothalamus turns off and the body moves less instantaneously.

This observation could critically an explanation for the lack of movement in obese people.

Further information on this topic can be found in the link below.