Fat gets a bad rap because it is implicated as the major culprit behind the obesity pandemic worldwide. The so-called fast-food diet that the United States has exported worldwide is blamed for the increase in body mass index (BMI), which is associated with health risks. Recent studies have emphasized that where you carry the fat matters in terms of health risks. For example, people carrying excess fat in the abdomen have higher risks of cancer and cardiovascular disease. It is clear that the biology of fat is complex. Fat, which is synonymous with lipids, plays an important role in our cells to maintain homeostasis. Lipids generate ATP and are involved in the synthesis of vitamins, hormones, bile salts, eicosanoids, and cellular membranes, as well as the regulation of cellular signaling. Cholesterol and phospholipids are essential components of membranes within the cell. The anabolism and catabolism of lipids is compartmentalized. Anabolism primarily occurs in the cytosol and endoplasmic reticulum, whereas the catabolism primarily occurs in mitochondria.