Causes of Obesity

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The causes of obesity are multiple and complex due to the combination of causes and contributing factors. It is generally accepted that the cause of obesity is an energy imbalance between calories consumed and calories expended through exercise and activities of daily living, with the body storing the excess of calories as fat.

Risk factors of Obesity

Obesity is not simply the result of eating too much. Epidemiological studies have detected a series of factors associated with obesity in the population.

Woman growing older from childhood to old age

Age. As one ages, the hormonal changes and a less active lifestyle contribute to the appearance of obesity.


Female gender. Mainly associated with childbirth and the menopause. Obesity also occurs in women that have polycystic ovary syndrome, which is an endocrine condition that prevents correct ovulation.

People of different skin tones

Race. There is a high level of incidence obesity in people of African descent and those of Hispanic origin.

Pie, meat and sausage

Unhealthy food. In the last 50 years, there is a universal trend to eat foods high in fat, salt, and sugar. Too many calories are consumed, with abuse of fast food, as well as drinks with a high calorie content.

A person lying on a sofa or bed representing sedentary lifestyles

Sedentarism. There is a decrease in physical activity due to a sedentary lifestyle, the automation of work activities, modern means of transportation and increased urban life.

Decrease of money

Socio-cultural. Obesity is associated with lower educational attainment and lower income levels linked to limited access to recreational facilities and lack of money to buy healthy foods.

A pitcher of beer and a Martini or cocktail glass

Habits. A consumption of incorrect foods, smoking and alcohol consumption.

Family and family tree indicating hereditary factors

Genetic factors. Some genetic studies have determined that obesity can be hereditary, with genes that influence the amount of body fat and its distribution.

Medicines, pills

Certain medications. Some drugs can cause a gain in weight if they are not combined with diet or exercise. Among these drugs are some antidepressants, anticonvulsants, steroids, antipsychotics, drugs for diabetes, and beta-blockers.

Can metabolism be accelerated naturally?

The energy imbalance that causes obesity can be corrected by accelerating the metabolism in a natural way. Exercise, especially anaerobic or strength training, is one of the main factors that can overcome this imbalance.

Substantiated information by:

Alba Andreu Martí
Lilliam Flores Meneses
Silvia Cañizares Alejos

Published: 17 August 2018
Updated: 20 January 2022

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