Lack of sleep definitely reduces a young adult's capacity to perform the basic metabolic functions.
Sleep deprivation results in altered glucose metabolism so that it takes longer for insulin, the major hormone regulating sugar levels in blood to be secreted.This is an early marker of diabetes.
In addition, there is a reduction in the rate of secretion of thyroid metabolic hormones which are important in the normal functioning of basal functions.
Lack of sleep also causes a reduction in the secretion of leptin, a hormone that suppresses appetite, so that you tend to eat more.
There is an increase in ghrelin production, and it increases appetite, so you tend to eat more.
There is an increased tendency to gain weight and towards obesity, hypertension, and other old age related diseases.
Finally,the aging process is accelerated.
If lack of sleep has related to depression, being nervous, or poor diet; yes it does.