The genetics of nutrition: a look at the hereditary influences on our eating behaviour

By Foodways

Nutrition plays an enormous role in our health and general well-being. Sustainable nutrition also conserves resources and thus contributes to environmental protection. But how does our genetic predisposition actually influence our eating habits? And why do many people find it so difficult to change their eating habits in favor of a more sustainable diet?

We wanted to know what part of behavior is inherited and why we find it so difficult to change it. That’s why we dived into the literature and compiled some exciting facts.

(Disclaimer: We are neither medical doctors nor health or nutrition counsellors and have not read all the literature on the subject. The contents are intended to give an impression).

Genetics – How genes affect eating behavior

When we look at the genetics of eating habits, it is not just about the metabolism of nutrients, but also about the genetic predisposition to specific nutritional needs, taste preferences and eating behavior.

• A classic example of the genetic influence on nutrient metabolism is lactose intolerance. Those affected only have small amounts of the enzyme lactase, which is needed to break down the sugar lactose contained in milk into glucose and galactose. A deficiency means that these people cannot tolerate dairy products well. The predisposition to lactose intolerance is genetic and usually occurs in people whose ancestors came from regions where milk and dairy products were not part of the diet.

• However, genes can also determine the need for certain vitamins or minerals. For example, some people need more folic acid. This is because they have a genetic variation in the MTHFR gene, which is responsible for folic acid metabolism. Folic acid plays a decisive role in cell division and DNA synthesis and contributes to the prevention of neural tube defects in unborn babies.

• Genes can even influence our taste preferences and eating behavior. People with a genetic variation of the TAS2R38 gene react more sensitively to bitter substances. They find certain foods such as broccoli, Brussels sprouts or coffee unpleasantly bitter and avoid them. Other people don’t taste sweets as strongly, which is due to a genetic variation in the TAS1R2 gene. They need larger amounts of sweeteners in order to experience a sweet taste. This is why they often tend to consume more sugar.

These examples illustrate that genetic predispositions can influence specific nutritional behavior.

Epigenetic – How nutrition influences genes

But wait, that’s not all. Epigenetic also plays an important role. Our environment, behavior, diet, exercise and other influences affect our genes. They can cause chemical changes in the RNA in the cell nucleus, which are ultimately passed on. This means that not only do the genes have an effect on us, but we also have an effect on the genes. These epigenetic effects are a completely new field of research – we recommend reading the book “Wir können unsere Gene steuern!” by Isabelle M. Mansuy, Jean-Michel Gurret and Alix Lefief-Delcourt.

We have therefore inherited genetic dispositions and epigenetic factors from our ancestors. So it’s no wonder that we sometimes find it so difficult to give up meat or sweets, for example.

Sustainable and healthy nutrition – how it can still succeed

However, our eating habits are not only determined by our genes, but also by many other factors such as our environment, our culture, our upbringing, our social environment, our stress levels and our emotions. These factors shaped the food likes and dislikes of our parents and grandparents, which they passed on to us. But our eating habits are also deeply rooted in us through our upbringing and culture.

In order to change our eating habits, it therefore helps to recognize these factors and find ways in which we can slowly change these habits. In doing so, we should consciously recognize and question cultural and family traditions. This takes a lot of motivation, willpower and patience. Changing our attitude towards food and ourselves can be very helpful.

After all, a sustainable lifestyle pays off in concrete terms for us and future generations. The good news is that epigenetic changes are fundamentally reversible. For example, the predisposition to type 2 diabetes can be reduced for future generations by changing our lifestyle.

Sustainable eating therefore not only has an impact on the environment and the climate, but also has a positive effect on our health and that of our descendants.