Body mass index (BMI) is predetermined by genetic factors that change depending on the type of diet or lifestyle one adopts during childhood, and can cause obesity later in life, according to a study.
A new study on obesity and genes
Why do some people get fat and obese, while others have a normal weight even though they eat the same?
Scientists believe that the answer lies in some biological processes that occur during childhood. A new study, conducted by a group of researchers from around the world led by scientists from the Imperial College London (United Kingdom), the University of Surrey, in Guildford (United Kingdom) and the University of Oulu (Finland), points out that genetics influences body mass index (BMI), but these genes change over the years.
The authors of the paper, which was published in Science Advances, found that genes determine the BMI of babies, but there are more than 100 genetic variants that can modify it when they grow up and become adults, and those genes begin to change during childhood, from 4-7 years of age, so if measures are taken against childhood obesity it’s possible to prevent it later in life.
For children aged seven years old, diet or lifestyle can influence the development of obesity as adults.
The study was conducted on 22,769 children who had their BMI and growth rate measured from two weeks of age to the age of 13. According to the researchers, environmental factors such as a diet high in sugars and fats, or living a sedentary life during childhood, causes a high BMI – that is, weight increase and fat accumulation as adults – because the genes of obesity with which we’re born turn on at that point.
The BMI is an indicator of body fat that varies over the years and has several periods of change. After birth it increases greatly until nine months of age, at which point it reaches its peak. Then it decreases until five or six years of age, and thereafter there is a rebound known as the adiposity rebound period. Actually, previous research cautions that the stage that begins at seven years of age or so is key in the subsequent development of obesity.
Modifications in two genes influence children’s BMI
The researchers also found that a variation in a region of the genome where the LEPR and LEPRT genes are found influences the BMI of children.
In adults this region of genes is involved in the activity of leptin, a hormone that produces fat cells and helps control hunger, and which according to some research is involved in the development of the brain early in life.
The study suggests that these genetic modifications aren’t related to weight regulation in adults and their effects are limited to children. The research is part of the Early Growth Genetics Consortium, a project that combines data from different genome association studies to identify genetic variants involved in human development, from birth to the old age.
Date: September 6th, 2019
By: Caridad Ruiz
Nutrigenomics Institute is not responsible for the comments and opinions included in this article
