Is obesity hereditary? Answered by a doctor

head of the bariatric medicine center of FMBA in Rostov-on-Don, surgeon, bariatric surgeon

“According to the latest data from the World Health Organization, about one billion people in the world today suffer from obesity. In a quarter of a century, their number has doubled. In 2022, scientists estimate that about 43% of adults are overweight. There are also significantly more children between the ages of five and 19, whose bodies are prone to pathological accumulation of fat”.

We understand to what extent in the excessive accumulation of adipose tissue “to blame” genetics and what section of medicine deals with this problem.

How to identify obesity?

The main way to identify obesity is to calculate the body mass index (BMI). It is equal to a person’s weight in kilograms divided by height in meters squared. For example, a person’s weight = 74 kg, height = 172 cm. Therefore, BMI = 74: (1.72 x 1.72 ) ≈ 25.01 kg/m².

This calculation is not applicable only to athletes and pregnant women. For all others, the following is true: if the BMI is less than 18.5, then the weight is below normal; from 18.5 to 25 – normal; values from 25 to 30 indicate the presence of overweight, if the BMI is above 30, we are talking about obesity.

When the patient has comorbidities (type 2 diabetes mellitus, hypertension, apnea, etc.) or BMI is over 40, this condition is called morbid obesity and is a reason for bariatric surgery.

Causes of obesity: environment or genetics?

Social factors play a significant role in the fact that the body of modern man spends less calories than he consumes. A sedentary lifestyle, stress, which is accompanied by impulsive snacking, high-calorie food with a lot of sugar and trans fats, uncontrolled snacking – all this creates favorable conditions for the accumulation of excess fat in the body. However, the role of genetic predisposition to obesity should not be underestimated.

Scientists have found out that from 200 to 500 different genes and their combinations influence the way the body assimilates nutrients, accumulates fat and signals that it is full. Nearly 43% of the population has the FTO (fat mass and obesity associated) gene, which can cause problems such as increased hunger, difficulty reaching satiety, compulsive overeating, a tendency to be sedentary and to store body fat.

A number of twin studies have shown that the contribution of genetic factors to BMI variation can be as high as 70-80%. Thus, it turned out that the heritability of obesity is not affected by whether the twins live together or separately. And in adopted children, BMI correlates with the BMI of their biological parents.

About 80 different syndromes have been described that include obesity as one of the clinical features. 30 of these are with an established genetic cause for development.

Doctors separate syndromal and monogenic obesity. In the first case, pathological accumulation of fat in the body occurs with chromosomal and other genetic syndromes. The second variant develops due to a mutation in the gene, which leads to a violation of the synthesis of proteins that regulate the processes of eating behavior.

It can also be considered proven on the basis of a large number of studies that children who are obese from an early age are more likely to have obese mothers. Moreover, the problem of overweight affects daughters more than sons.

The general increase in obesity rates in society is due to a complex set of reasons and is caused by a complex interaction of external factors and individual hereditary predisposition. It certainly plays a role in the development of obesity, as genetics can influence metabolism or cause hormonal abnormalities.

However, it is behavioral factors such as poor diet, lack of physical activity, stress, and sleep deprivation that increase the chances of individuals becoming chronically obese.

Can obesity be “eliminated” from inheritance?

The presence of a genetic component means that even if a child is cured of obesity before conception, no one can guarantee that the child will not be overweight.

The risks of giving birth to a child who will eventually become overweight can be minimized, even if you have a predisposition to obesity or overweight. For example, it has already been proven that children whose mothers took supplements with polyunsaturated fatty acids (fish oil) during pregnancy have an increased BMI by the age of 10.

Scientists believe that factors such as smoking during pregnancy or maternal diabetes change the growing child’s metabolism, and this later manifests itself in obesity.

It is not possible to change a genetic predisposition to obesity, but it is possible to control weight and improve health. If obesity is inherited and manifests itself at an early age, the child needs to be monitored by a doctor and, in the case of syndromal obesity, by geneticists who will prescribe an individualized treatment plan.

What steps should be taken to reduce the risk of complications and improve the health of an obese child:

• a healthy diet: more fruits, vegetables, whole-grain foods, proteins, and less fat, sugar, and processed foods;
• physical activity – it will help burn extra calories and strengthen muscles;
• supporting your child’s psychological well-being, as obesity can affect their self-esteem and confidence levels;
• regular medical check-ups to monitor weight, cholesterol, blood sugar and other indicators;
• discussing obesity and healthy lifestyles within the family. It is important that all relatives support the child and help him or her achieve their goals.

Tips for adults with a tendency to be overweight

Genetically determined obesity may not show up right away, but rather in older adulthood. If you know you are at risk, have obese relatives, especially close relatives, you should follow these rules:

1. Adhere to a healthy and balanced diet. Avoid fatty, high-calorie and processed foods. Include more fruits, vegetables, beans, nuts, and grains in your diet.

2. Engage in regular physical activity. This can be cardio exercise (running, swimming, bicycling) or strength training (working out with dumbbells, push-ups, squats).

3. Monitor your weight and consult a specialist (nutritionist, trainer, endocrinologist) if necessary.

4. avoid stressful situations and relax (meditation, yoga, breathing exercises).

5. Get enough sleep, as lack of night rest and hormone imbalances can lead to weight gain.

6. Avoid alcohol and smoking – they can contribute to body fat accumulation.

7. Maintain psychological balance and a positive attitude toward yourself. It is important to remember that each person is unique and capable of making changes in their life.

Bariatrics in genetic obesity: what is it and how does it help?

Over the past three years, the number of people in Russia who decided to get rid of obesity with bariatric surgery (a method of treating obesity through surgical intervention) has increased by 172%.

Bariatrics is a section of surgery that deals with the treatment of obesity. It includes surgeries such as gastric banding, gastric bypass, and other interventions that reduce the size of the gastrointestinal tract. Moreover, after bariatric surgery, the patient not only reduces body weight, but also normalizes the production of hormones associated with intestinal function.

In 98% of cases, obesity is the result of excessive caloric intake. More often than not, hormonal disorders are a consequence of excess fat mass, not the cause. Therefore, bariatrics, or as it is also called, metabolic surgery, is one of the effective ways to treat obesity. The surgery has been proven highly effective in treating type 2 diabetes mellitus in people whose BMI is above 35.

Patients with any type of obesity are evaluated by a pool of specialists, and the decision whether or not to have bariatric surgery is made on a case-by-case basis, taking into account any chronic conditions, be it excess hormones or bulimia.