I also fund that sugar also increase methyliation.
( High levels of glucose were also found to directly increase DNA methylation)
Interestingly, DNA methylation of 4875 CpG sites in adipose tissue was affected differently depending on the diet. Fasting may also affect the DNA methylation pattern. Indeed, 36 h of fasting affected the methylation level of the genes encoding leptin and adiponectin in a birth weight dependent manner in adipose tissue.
https://www.sciencedirect.com/science/article/pii/S221287781731102X
Everything above explain why when we fast we fell better, when eat sugar we feel bad, crash with vitamin B and D.