The most common answer is diet and exercise, with experts advising you to ensure you eat a healthy, balanced, kilojoule-controlled diet, combined with frequent physical activity. But many people still struggle with their weight despite eating healthy, following a strict dieting and exercising extensively.
Obesity is a leading health problem in the world, as it's associated with many related health conditions, including high blood pressure, high blood sugar levels and a poor blood lipid profile. People with obesity are also at a much higher risk of heart disease and type two diabetes.
Besides overeating and a lack of physical activity, what exactly causes obesity?
The first cause could be genetics. According to Harvard Medical School, your genes can affect your susceptibility to gain weight. Another cause is the heavily processed and sugar-sweetened junk foods that society consumes, which people tend to overeat.
But hormones can also influence a person's weight. Insulin resistance can cause weight gain, because insulin is a very important hormone that regulates energy storage. This causes energy to get stored in fat cells, which in turn causes weight gain.
Weight gain can also signal low levels of thyroid hormones, which is a condition called hypothyroidism. Your thyroid is a vital hormone gland that has a huge influence on the metabolism, growth and development of your body. Many of the body's functions slow down when the thyroid does not produce enough of these hormones. Common signs of an underactive thyroid are tiredness, weight gain and feeling depressed.