While I have not seen his videos, I am sure that he probably feels that a certain amount of aging control is programmed into our genes. I definitely see this and there is a sequential step to each stage of life. This involves genes that are turned off in our cells.
One of the early steps involves puberty. At that period of time, the production of Melatonin significantly drops off. You can even delay puberty by taking significant amounts of melatonin at night when that starts to occur.
The next significant changes occur when DHEA production in the adrenals occurs.
Taking DHEA and Melatonin can significantly improve the quality of life in the years after 40 to 50 and increases lifespan with nothing else added. Taking DHEA in the right amount can even significantly reduce the graying of hair in many cases ( but not all as there are also other nutritional factors ).