Discuss how fat cells develop in number and size, and how this may lead to obesity and other health risks.

Question

What will be an ideal response?

Answer 1

hen “energy in” exceeds “energy out,” much of the excess energy is stored in the fat cells of adipose tissue. The amount of fat in adipose tissue reflects both the number and the size of the fat cells. The number of fat cells increases most rapidly during the growing years of late childhood and early puberty. After growth ceases, fat cell numbers may continue to increase whenever energy balance is positive. Obese people have more fat cells—as well as larger fat cells—than healthy-weight people.
As fat cells accumulate triglycerides, they expand in size. When the cells enlarge, they stimulate cell proliferation so that their numbers increase again. Thus obesity develops when a person’s fat cells increase in number, in size, or quite often both. When “energy out” exceeds “energy in,” the size of fat cells dwindles, but not their number. People with extra fat cells tend to regain lost weight rapidly; with weight gain, their many fat cells readily fill. In contrast, people with an average number of enlarged fat cells may be more successful in maintaining weight losses; when their cells shrink, both cell size and number are normal. Prevention of obesity is most critical, then, during the growing years of childhood and adolescence, when fat cells increase in number. Researchers are exploring ways to induce fat cell death—which would decrease the number.
As mentioned earlier, excess fat first fills the body’s natural storage site—adipose tissue. If fat is still abundant, the excess is deposited in organs such as the heart and liver. Fat that accumulates outside of adipose tissue—called ectopic fat—disrupts normal metabolism and contributes to the development of diseases such as heart failure and fatty liver. As ectopic fat accumulates, metabolic changes that indicate disease risk—such as insulin resistance—become apparent and chronic inflammation develops.