It is believed that a person’s dietary preferences are largely determined by culture and upbringing. People who are trying to get rid of excess weight often hear the same advice – to change their diet and eating habits or just eat less. The advice is sound, but is it so easy to change your eating habits if they are “predetermined” by your genes?
Researchers at Massachusetts General Hospital, Harvard Medical School conducted a full genomic DNA analysis of 282,271 participants in the UK Biobank (n=191,157) and Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium (n=91,114) studies and found 26 genetic loci associated with a preference for foods rich in protein, carbohydrates or fat.
This is one of the largest full-genome studies of eating behavior and dietary factors to date, published in 2021 in Nature Human Behaviour. It confirmed the predominant role of molecular genetic factors in the regulation of eating behavior and dietary preferences in humans.
Does this mean that a person is “destined” to be fat or thin, sweet-toothed or low-eating?
To understand this, it is necessary to understand what is gene polymorphism, and what factors affect the expression of our genes, i.e. which of them will work, and which will remain as a “code”.
Gene polymorphisms are various inherited variations in the structure of DNA. Gene polymorphisms mainly determine individual differences in any of a person’s qualities: eye or hair color, blood type, nose shape, etc. Some of the polymorphisms can be one of the factors of predisposition to diseases, for the development of which it is necessary to have such hereditary predisposition plus the impact of unfavorable external conditions: the nature of nutrition, the intake of toxins into the body, vitamin deficiency and so on.
What is epigenetics?
In addition to heredity, our DNA is affected by everything that happens to us during our lives. Epigenetics is a branch of genetics that studies how our behavior and environment affect the way our genes work. Unlike genetic changes, epigenetic changes are reversible.
The genome is a “passport” in which all possible variants of an individual’s development are recorded, but the program by which the organism will develop depends largely on epigenetic factors. In other words, the work of genes directly depends on the environment.
And the first environment at the stage of the earliest development of any human being is the mother’s organism. Genetic polymorphisms laid down at the intrauterine stage largely depend on epigenetic factors affecting the future mother. In particular, studies have shown that exposure to harmful chemical factors in the mother’s body leads to changes in the epigenome that contribute to the formation of a state of systemic inflammation with lifelong effects and consequences for the newborn. This is why it is so important what kind of lifestyle a woman leads long before the planned pregnancy. What and how she eats, drinks, whether her body is exposed to harmful chemical and other factors.
Active study of the human microbiome has shown that the nature of nutrition of the mother during pregnancy and breastfeeding has a direct impact on the formation of intestinal microflora of the fetus and newborn, and the composition of the microbiome depends on the food preferences of the person and his overall health. Thus, the formation of healthy habits begins in utero.
