Do the Genes Fit?

These genes do not refer to a favourite pair of pants, but to the human genetic make-up. Is it possible that our genes are responsible for the obesity epidemic? When first looking at the research, it might seem that way, but in fact, genes are only part of the answer.

Rewind to a few thousand years ago. Imagine being a hunter-gatherer living in a world where food is scarce and physical activity is plentiful. Since no one knows when the next meal will be, it is important to store extra energy when food is available. Fast-forward to the present day. Our genetic make-up is almost the same as the hunter-gatherers, however our modern lifestyle has changed dramatically.

Today we live in a sedentary society and are surrounded by food. It is common for a person to spend much of the day driving, working at a desk, or watching television. It has also become easy to choose low-cost, high fat and high sugar foods for snacks and meals. This type of lifestyle may promote overeating. Excess energy the body does not need will be stored as fat.

Although we share almost 99% of our genetic make-up, there are small differences between us. The risk of developing obesity is affected by how these genetic differences interact with lifestyles and the environment. This explains why some people making similar lifestyle choices may gain or lose weight more easily than others. Also, people who share their genetic make up will be affected by obesity in a similar way. This includes people such as twins or parents and children.

The complex link between genes, lifestyle, and obesity can make it seem difficult to be healthy. Luckily, there are many choices we can make to improve our health. Eat more vegetables. They are low in calories, taste good and help us feel full. Take a walk during a break at work or school. Moving around can:

  • § Help strengthen muscles and bone.
  • § Improve mood and mental health.
  • § Reduce the risk of developing many chronic diseases. Are genes responsible for the obesity epidemic? Only partially. The obesity epidemic is the result of a complex link between genes and lifestyle. We will need to work together if society is to successfully tackle this epidemic.

WRITTEN BY THE PUBLIC HEALTH NUTRITIONISTS OF SASKATCHEWAN

Originator: Calysta Adams (Dietetic Intern) and Victoria Jurgens RD, Prince Albert Parkland Health Region

Editing Buddy: Jennifer Miller RD

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