In in the 70's and 80's in Romania, the dictator outlawed contraception (ex. condoms), forbade abortions, and taxed families with fewer than 5 children. As a result, the birth rate skyrocketed, but families could not afford the children they were forced into having and abandoned them to government run orphanages with bad staff. Child to caregiver ratios were often 15:1, so the children were deprived of healthy attachment with at least one adult. These children had lower intelligence scores and double the anxiety of children in quality foster care centers.
The Harlow's monkeys raised in total isolation (without an artificial mother), bore lifelong scars. As adults, when placed with other monkeys their age, they either cowered in fright or lashed out in aggression. They were also incapable of mating when they reached sexual maturity. If they impregnated these monkeys, females were often neglectful, abusive, and even murderous towards their first born (Abuse breeds abuse).
Another experiment confirmed the abuse breeds abuse phenomenon.
Muscular strength, reaction time, sensory keenness, and cardiac output begin to decline, my susceptible to disease, increased accident risks. Women get menopause, and woman and men have a gradual decline in fertility.
Memory declines, atrophy of the frontal loves accounts for their impulsively (old people ask "Have you put on weight?") , take more time to react because the neural processing is slower and there is diminished sensory abilities.
The more active you are, the better your memory is, the more reactive and sharp you are, and the more your telomeres are maintained.