Therefore, the reduction in overall energy intake, but particularly in carbohydrates, protein, and to some extent fat, results in lower concentrations of serum glucose, amino acids, and certain growth factors (insulin, leptin, and IGF-1), as well as decreased fatty acid synthesis in the host, leading to the inhibition of cancer cell growth and presumably also to the synergistic action with anticancer medications [90]. Here, INS is linked to cancer.