Sure thing, there is no desire to eat when you’re feeling terribly sick. Any fever is followed by the absence of appetite for at least half a day. Tuberculosis figures as a consumption due to this symptom. Almost half of the recently surveyed patients report extreme weight loss; 1/3 of them end up anorectic. The best way to describe why it happens is through regulatory (gut) hormones. A peptide YY is a well-known appetite suppressor in the medical field, and it attacks people who suffer from TB.