**2. Energy storage in the body**

Under normal metabolic conditions, some of the excess glucose is stored as glycogen, mainly in the liver and muscles, and further excess energy is stored as fat mainly in the adipose tissue. Fat in the body consists of triglycerides (TGs), which are transported to the adipose tissue in the form of chylomicrons from the intestine, and also produced from excess glucose in the adipose tissue and the liver. Under the feeding conditions, glucose is metabolized mainly in adipocytes and hepatocytes via glycolysis to produce pyruvate, which is then converted to acetyl-CoA and combined with oxaloacetate to enter the TCA cycle as citrate in mitochondria. Excess citrate is transported to the cytoplasm and converted to acetyl-CoA, which is then used as a substrate for fatty acids synthesis via malonyl CoA produced by the ratelimiting enzyme, acetyl-CoA carboxylase. Fatty acids are esterified with glycerol to produce triglycerides and stored in the adipose tissue.
