A lack of adequate dietary magnesium is associated with a lack of appetite. This may be due to chronic systemic inflammation caused by the deficiency, which can disrupt normal hunger mechanisms and hormones related to appetite function. A center in the brain called the hypothalamus is also associated with appetite. Magnesium is necessary for normal hypothalamus function.
A lack of appetite may sometimes be associated with an electrolyte imbalance involving magnesium and calcium. Magnesium and calcium, two of the body's key electrolytes, work in tandem to maintain a correct balance in the body. When magnesium is low, it can cause a drop in calcium levels, which is also sometimes associated with poor appetite.