The Obesity Gene According to Science

Genetic changes in DNA partially explain obesity. Scientists continue to study the topic to find more answers. In this article, we'll explain what discoveries have been made and how they affect the treatment and prevention of obesity.
The Obesity Gene According to Science

Last update: 15 August, 2021

Historically speaking, you could say that what we know about the obesity gene dates back to 1962. The scientist in question is James Neel, a geneticist. He proposed a theory that continues to be debated in scientific circles today.

James Neel wondered why diseases closely associated with obesity, such as diabetes, were becoming more common over time. It would be logical to assume that occurrences of the conditions wouldn’t increase over time throughout human history. However, on the contrary, the conditions have become more widespread.

To explain why diabetes continued to affect more and more people, Neel proposed the existence of a gene. This gene would serve the human species to overcome times of famine, which have frequently occurred throughout history. Through this ‘thrifty genotype,’ humans would accumulate extra fat to be able to survive famines.

According to James Neel, this obesity gene was logical and even an advantage for those lean times. However, as the years passed there were fewer cases of widespread famines throughout the world. Therefore, this gene caused people to accumulate unnecessary fat, which led to obesity, as well as a higher occurrence of diabetes.

With that in mind, what originally helped our ancestors to survive is today a disadvantage in an increasingly convenient world. Today we have a much more sedentary lifestyle and greater availability of foods rich in fats and sugars.

The obesity problem

A child standing on a pair of scales.
Doctors calculate BMI to determine obesity.

Obesity is a serious global public health problem. It’s an epidemic that’s spreading throughout the globe, crossing borders, and affecting millions.

Obesity is classified as a chronic disease. What exactly is obesity? It’s an excess of fat tissue that accumulates in the body. How do doctors determine if someone is obese? They use the body mass index (BMI). The doctor calculates BMI using a formula that divides body weight in kilograms over height in meters squared.

Statistically, 22 percent of the world’s adult population suffers from obesity. Some estimates are even larger and put the figure of overweight or obese people at around a third of the world’s population.

Of course, the problem isn’t just one of appearance. It affects many areas of the person’s life and health. That’s why it’s so important to discover and define the obesity gene. Obesity is associated with other diseases such as diabetes and high blood pressure, in addition to affecting the person’s quality of life. This involves, but isn’t limited to, the following areas:

  • Social isolation
  • Depression
  • Sexual problems
  • Difficulties at work

Current discoveries about the obesity gene

In 2007 investigators made a fresh discovery about the obesity gene. Scientists identified the FTO gene and associated it with obesity. Their experiments showed that if this gene is defective, the body tends to store more energy than it needs, rather than burning it.

However, genes don’t explain obesity in everyone. For instance, about 44 percent of Europeans carry this gene, which is less than half the population.

Other more recent studies have also explained in detail how this obesity gene alters the levels of a hormone called ghrelin, better known as the hunger hormone. If the FTO gene is altered, ghrelin overreacts, making the person consume more food, especially high-fat foods.

Can genetics be reversed?

Exercise is essential in combating obesity.
Exercise is one of the most important ways to treat obesity.

Scientific studies all agree on something: the obesity gene is not the only factor that affects a person’s weight. Lifestyle is an even more significant factor than genes. Other factors also have an impact. And of course, you can change or adapt your lifestyle, while you can’t do anything about your genetics.

Here are some areas within your reach that you can use to combat the effects of genetics.

  • Exercise. The recommendation is to do more than an hour and a half of physical activity a week. In addition to helping prevent obesity, exercise also contributes to preventing other chronic diseases.
  • Healthy eating. It’s essential to have a balanced and varied diet. You should only consume the calories you need for your level of physical activity. You should avoid high-fat and high-sugar foods.
  • Weight control. Of course, it’s not good to obsess about your weight. However, weighing yourself from time to time helps you understand how your body’s going. You can also make any necessary adjustments.
  • Consistency. Lifestyle changes need to be permanent to make a lasting difference. Persistence in areas such as exercise and eating healthy will get you good results in the short, medium, and long term.

Science continues to study the obesity gene

In conclusion, scientists continue to investigate genetics. But of course, we’re still far from discovering drugs that could help regulate the FTO gene and ghrelin hormones.

The obesity gene does exist, as we’ve seen. However, it’s not the only thing that determines whether a person becomes obese. Lifestyle, exercise habits, and a healthy diet are the true pillars of obesity prevention and treatment.

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