Are your genes to blame for your obesity? Maybe it’s time to debunk this myth

Genetics play a central role in obesity, as they may influence: 

• how much food we tend to eat at each meal 
• how much energy is needed to run our body’s basic functions 
• how and where excess calories are stored as fats in our bodies. 

Genes are the functional units made up of DNA. They play an important role in the development of a human body.¹ They act as units of heredity and are responsible for transferring same instructions from a parent to their offspring, including one’s physical appearance, such as height, eye color, hair, and skin. Body weight is not an exception! 

Most of our genes are same, but differences occur when there are variations in the DNA. These variations contribute to each person’s unique features.² Studies have suggested that highest heritability is seen in body weight and visceral circumference among all traits. 
 

Obesity: The Indian scenario 

According to a research, genes play a role in obesity by affecting an individual’s metabolic rate, body fat distribution, and appetite.³ Responses of individuals towards the storage and utilization of energy in their body largely depend on genetic variations.⁴  

In developing countries such as India, the prevalence of overweight and obesity is increasing faster than the global average due to genetic variations. This in turn contributes to the risk of metabolic diseases, including abdominal obesity, insulin resistance, hypertension, atherosclerosis, and type II diabetes.⁵ 

Obesity is a serious medical condition that needs professional support. It results from high–calorie food intake, less physical activity, and genetic involvement to some extent. In many cases, obesity can be prevented or managed with a combination of diet, physical activity, and medications.

 Key players of obesity  

Apart from genes, environmental factors such as stress levels, sleep deprivation, high–fat and carbohydrate–rich diet, and low physical activity  are the contributing factors to weight gain.

 For people who have been overweight for almost their entire life or those who cannot lose weight despite continuous exercises, dietary supplementations, and low calorie intake may require individualized interventions and support to be successful in maintaining a healthy weight.

References 

1. Harvard obesity prevention source. Genes are not destiny. [Internet] [cited 2021 Feb 20]. Available from:  https://www.hsph.harvard.edu/obesity-prevention-source/obesity-causes/genes-and-obesity/ 
2. CDC. Behavior, environment, and genetic factors all have a role in causing people to be overweight and obese. [Internet] [cited 2021 Feb 20]. Available from: https://www.cdc.gov/genomics/resources/diseases/obesity/index.htm#:~:text=LinkedIn-,Behavior%2C%20environment%2C%20and%20genetic%20factors%20all%20have%20a%20role%20in,to%20be%20overweight%20and%20obese&text=Obesity%20results%20from%20the%20energy,calories%20than%20their%20body%20burns. 
3. Harvard Health. Why people become overweight. [Internet] [cited 2021 Feb 20]. Available from:  https://www.health.harvard.edu/staying-healthy/why-people-become-overweight.  
4. CDC. Obesity & genetics: What we know, what we don’t know & what it means. [Internet] [cited 2021 Feb 20]. Available from: https://www.cdc.gov/genomics/resources/diseases/obesity/obesknow.htm#:~:text=Obese%20individuals%20have%20genetic%20similarities,affect%20gene%20expression%20and%20function%3F. 
5. Luhar S, Timæus IM, Jones R, et al. Forecasting the prevalence of overweight and obesity in India to 2040. PLoS One. 2020 Feb 24;15(2):e0229438.