Genetic Differences Can Determine Your Body Weight

There are more reasons why genes can influence a person’s tendency to gain weight. Let's examine them.

Basal Metabolic Rate

Your BMR or basal metabolic rate is a measure of how much energy you burn when you are at rest. The lower your BMR, the easier it is for you to gain weight. However, your BMR may vary slightly according to certain conditions. Eating a very low-calorie diet, for example, can decrease your BMR, while severe physical stress increases BMR.

Set Point

One theory suggests that the body tries to keep its weight within a specific range or set point, which is influenced by one’s genetic makeup. However, actual body weight is influenced by lifestyle and environmental factors. It is believed that the set point may adjust to a new level over time and may be affected by exercise, overeating, certain medicines, and medical conditions.

Body Signals

Your body gives you certain signals such as hunger, appetite, and fullness (satiety), which influence how much you eat, although you can ignore these for short periods of time. Environmental factors can also influence these signals. Hunger and satiety are normal sensations that make you either want to eat or to stop eating. These are controlled by interactions involving a region in the brain called the hypothalamus, your blood sugar levels, the production of certain hormones, and the stretch receptors in the stomach.

Research shows that individuals who carry genes called FTO (fast mass and obesity-associated gene) and BDNF (brain-derived neurotrophic factor gene) have a greater risk of obesity. These genes affect the part of the brain that controls eating and appetite and are linked with overeating. A large study involving more than 2,000 participants found that variations in the FTO gene were significantly associated with an increased tendency to eat more meals and snacks per day, with greater consumption of energy from fat and sweets. It also showed that individuals who had variations in the BDNF gene tend to consume more servings of dairy, meat, eggs, nuts and beans. They were also found to consume about 100 more calories daily, which could have a considerable influence on body weight.

See Also: Appetite Hormone Glucagon Fails In Obese People

According to scientist Joseph Majzoub, MD, chief of the endocrinology division at the Boston Children’s Hospital, gene mutations that are known to cause obesity in humans account for less than five percent of obesity in our society, and are not totally responsible for the on-going epidemic. However, these mutations have led scientists to the discover mechanisms that may help explain energy balance in humans, which may someday lead to the development of drugs that can affect these pathways to prevent obesity, either by decreasing appetite or promoting burning of calories.