The 7 main causes of obesity

Obesity is one of the most epidemic diseases in both developed and developing countries. And therefore knowing the main causes of obesity will help provide proper ways to prevent its spread.

In this guide, I will focus on providing you information on the 7 main causes of obesity.

What is body Weight?

Human body weight can simply be explained as a total Person's mass that is measured on a weighing scale and excludes heavy items located on the person such as a wristwatch, shoe, and mobile phone.

Medically, less or more bodyweight is regarded as an indicator of determining how well an individual is.

According to Devine formula, an ideal weight for male adults is 50kg and that of females is weighed to be 45.5kg.

Generally, a body with Body Mass Index (BMI) between 18.5 and 25 can be regarded as a normal body (non-obese). And a bodyweight with a Body Mass Index that is lower than 18.5 or more than 25 can be regarded as underweight or overweight respectively. While a bodyweight of Mass Index of 35 and above can be regarded as obesity.

The too much bodyweight loss or gain can be a result of many factors. Some factors may be prenatal or postnatal influence, while others may be environmental, hormonal, poor lifestyle and poor eating habits.

Related: How to land excess fat safely and naturally in the dustbin

Main Causes of Obesity

Obesity can be caused or attributed to various hormonal imbalance, the genetic constitution of an individual,  mutation, poor lifestyle and eating habits.

Environmental factors and diseases may also play a significant role in causing obesity.

Keep reading to unlock the 7 main causes of obesity:

Main Causes Of Obesity #1: Hormones Imbalance

Hormones are biological substances synthesized in a special tissue called glands. The main function of hormones is the transfer of information in a biological system from one tissue to another through a bloodstream.

High or low secretion of these hormones may lead to what is called hormonal imbalance.

And one of the key players to weight gain in the human body is hormonal imbalance. For instance, high glucose level in the body was found to be associated with insulin resistance which in turn lead to body weight gain.


Insulin is a hormone in the biological system that regulates the body glucose levels in the bloodstream. When there is low insulin in the blood, more glucose is released in the bloodstream, and when there is more insulin in the blood, more glucose will be converted to fats.

In either way, both low and high insulin production will negatively affect your body weight.


Hypothyroidism was also associated with body weight gain.

Hyperthyroidism is the underproduction of thyroid hormone by the thyroid gland and this condition leads to body fatigue and cholesterol accumulation in the bloodstream.

The accumulated cholesterol and pyruvic acid increase the osmotic pressure of bloodstream and hence more water is absorbed into the bloodstream. This increases the size of the body, and hence obesity.


Ghrelin is another important hormone and is at the forefront when it comes to body weight gain or loss. In fact, this hormone is commonly called "Hunger hormone".

Ghrelin helps trigger appetite.

It is produced in the stomach. High production of Ghrelin stimulates overconsumption of foods, which in turn leads to obesity.


Estrogen is another hormone in the body that can contribute to body weight gain or loss.

Hypersecretion of estrogen was found to cause insulin resistance. When the level of estrogen in the body is high, the production of insulin will be depressed, which in turn leads to high glucose levels in the body. This leads to body weight gain.

Moreover, during menopause women were found to gain weight when the level of estrogen drops. However, thorough research needs to be made here.


Cortisol is a hormone in the body which helps in energy distribution to where the energy is needed in the body.

Moreover, it responses to stimuli like stress.

This means that the more body is in a state of stress the more cortisol will be produced.

So when the body is in a constant state of stress, more amount of cortisol will be secreted by the body.

This high production of cortisol also increases the amount of insulin in the body, and hence more glucose than normal are converted into fat.

This, in turn, increases visceral fat deposition, stimulates the maturation of cells and of course obesity.

Main Causes Of Obesity #2: Genetic constitution of Individual

This is a very important part of the human body or animals in general. It contains all the hereditary information which is transferred from parents to their offsprings.

In this case, if the parents of an individual have obese genes in their genetic makeup, then there is a high probability that their children will be obese.

Main Causes Of Obesity #3: Mutation

Mutation is an abnormality in genes caused by excessive radiations, carcinogens, free radicals, metabolic disorders, prenatal and postnatal influences.

In this case, an individual may inherit normal genetic makeup from his parents, but because of one or two environmental factors, the genes may be muted or altered.

Prenatal and postnatal influences may also play a role in changing the genetic makeup of an individual. This type of mutation happens during meiosis When genes are crossing over.

The mutant gene, the gene that is resulted from mutation, maybe an obese gene or favor weight gain.

 This makes the affected individual obese.

According to one study in mice from Boston Children's Hospital found that mutation in mice increases weight gain.

In this study mice with affected genes (Mrp2) were found to gain more weight than their normal counterparts even when they are fed on the same meal.

Main Causes Of Obesity #4: Poor Lifestyle

Poor lifestyle may also contribute greatly to weight gain. For example, too much watching of television was found to contribute to excess weight gain.

 A person who is not exercising his body or engaging in physical activities may accumulate a high amount of cholesterol in his body.

This cholesterol will be stored in adipose tissue if not used by the body or burn through physical activities and exercise.

As this cholesterol continues to accumulate in the body over time, the body will become obese.

Main Causes Of Obesity #5: Poor Eating Habit

Some people do not have a  limit when it comes to eating. They take anything food which crosses their way.

Eating food with a poor balance diet such as unhealthy diets, Red meat, heavy fats food and unhealthy fats and drinks with too much surgery substances such as refined carbs increase the chance of obesity.

Ideally, under normal conditions, there are various mechanisms in the body that sends message to the brain that you are full and you stop eating.

However, overconsumption of foods containing fructose tends to accumulate more fats which later increases leptin production.

This makes the body become used to leptin, which later makes the brain to stop receiving signals to stop eating. This causes body weight gain.

Main Causes Of Obesity #6: Environmental influence

 Environmental factors such as harsh climatic conditions, toxins and lack of safe area for exercising may also play a major role in weight gain.

These factors indirectly influence weight by changing the normal physiological functions (such as the production of hormones and enzymes secretion) of the body.

For example, toxins stimulate low production of thyroid hormone and a low amount of this hormone was found to increase body weight gain. Unfavorable climatic conditions such as high or low temperature can denature the biological structure and functions of enzymes, which invariably affects one or more body physiological functions.

Main Causes Of Obesity #7: Disease

Disease is an abnormal condition of the body or mind. People with type 1 and 2 diabetes were found to gain more weight than normal people.

Polycystic Ovary syndrome in women was found to lower estrogen levels in the body. This estrogen contains a biochemical substance called estradiol, which controls the metabolic process in the body.

 So when the level of estradiol drops, the rate of metabolic activities in the body also drops to the extent that it will affect the metabolic process of glucose.

So when the metabolism of glucose is lowered in the body, this leads to an increase or too much amount of glucose in the bloodstream or body, which later leads to an increase in body mass.


Obesity does not only cause an increase in skinfolds and belly fats but also obesity can increase the chances of the body's exposure to various diseases.

Below are some of the few and most important diseases that can be caused by obesity:

1. Cardiovascular Diseases
2. Hypertension
3. Hepatitis
4. Breast Cancer


Hope this guide gives you excellent help in understanding the causes of obesity. I would love listening to your views about bodyweight gain. So do write to me in the comment section below.

Written by Idris Ya'u

Post a Comment

Previous Post Next Post