Obesity is genes, bad habits or predispositions?

When is obesity diagnosed: BMI or body composition analysis more important?

The most popular and at the same time the simplest tool for diagnosis Obesity is an indicator of body mass BMI (body mass index). It is a formula in which body weight (in kg) is divided by height (expressed in meters) squared. The range of normal body weight is in the range of 18.5-24.9 kg/m²excess weight 25-29.9 kg/m², and obesity is recognized by the result of 30 kg/m². Due to the lack of distinction in the BMI formula of body composition, it is usually used mainly for screening.

Strength trainers with large musculature may get a result that indicates overweight or obesity, which is not really reflected in reality. Therefore, one of the next tools for assessing obesity is the measurement of waist circumference. This area was chosen for the measurements because of the observed correlation between waist circumference and increased risk of heart disease, metabolic disorders, cancer and premature death. The correct result for women should be less than 80 cm, and for men less than 94 cm.

Meanwhile, with the development of research, it turned out that Both BMI and waist circumference are still not completely reliable indicators. There are people with the TOFI (thin outside fat inside) phenotype, who have a normal body mass index, but have excessive body fat mass and too little muscle tissue.

To measure body fat content, it is necessary to perform a study of body composition or electrical bioimpedance. Such a measurement can be done in the office of a nutritionist and, increasingly, in the gym. Aby the result of the analysis of the composition It is best to do it in the morning after the morning toilet and avoid alcohol, physical exertion and smoking on the day before the examination.

Why is obesity a disease?

For years, adipose tissue was considered only the body's energy store. However, in the results of many studies it has been proven that it secretes a number of substances that affect the functioning of organs and tissues. Currently, adipose tissue is said to be another endocrine organ due to the fact that it secretes many proteins that exhibit an action attributed mainly to hormones. A certain amount of adipose tissue is necessary, for example, in the process of puberty and preservation of fertility, but its excess in the body provokes a pathological condition. Particularly dangerous are fat cells localizing within the abdomen (here we are talking about visceral adipose tissue located around the organs).

Adipose tissue plays a huge role in metabolic processes:

• It secretes many substances that not only affect the regulation of hunger and satiety (leptin, visfatin, resistin), but also increase inflammation (interleukin-6).
• affects the metabolism of steroid hormones (aromatase, dehydrogenase).
• Fat cells have many receptors for insulin, glucagon, TSH or angiotensin, among others, which can hinder their proper functioning in the desired areas of the body.

Although all these names sound complicated, they show how a complex “organ” with multidirectional action is adipose tissue. Its excess leads to insulin resistance, impaired glucose tolerance and, finally, type 2 diabetes.

In addition, it affects the development of hypertension, impaired cholesterol metabolism, develops chronic inflammation of the body and increases the risk of blood clots. Unfortunately, each of these disorders entails further complications and contributes to the development of metabolic syndrome. Advanced obesity typically requires drug therapy to break the cycle of mutually driving disorders.

Genetic determinants of obesity

To date, the gene directly responsible for obesity has not been found. Mutations of individual genes, as well as their entire complexes, can be affected, which can translate into disorders of the metabolism of components, absorption or appetite.

Obesity may also be a component of rare genetically determined syndromes. Their pathogenesis is not fully understood, but often results from damage to more than one gene. In addition to pathological obesity, caused, among other things, by hyperphagia and a reduced basal metabolism by close to 15%, they are also accompanied by other malformations (intellectual disability, organ disorders).

• Multigenic obesity

The most common type of obesity is multigene-related. This type of obesity is the result of gene—environment interactions. The susceptibility to obesity is determined by genes, but it is quantitative and qualitative diet composition and physical activity affect whether there will be excess body weight or not. Depending on the genotype, to varying degrees, there is an increased tendency to obesity. However, there is a correlation between obesity and physical inactivity. The introduction of regular exercise and control of the proportion of fat in the diet will be the best way to fight extra pounds and protect against the risk of obesity.

• Genetic testing

More and more dietetic clinics are proposing to perform genetic tests to personalize nutritional recommendations. Awareness of the carrier of specific gene polymorphisms that increase the risk of metabolic disorders can be used when introducing an intervention. Keep in mind that such a study does not take into account all genes, and focusing on a selective group can carry some risks.

Influence of intestinal microflora on obesity

The microbiota that inhabits the human body is characterized by enormous diversity. Depending on the section of the gastrointestinal tract, different species of microflora, characteristic for a given part of it, are distinguished. Differentiation is essential because these bacteria have different metabolic activities that affect human physiology. They facilitate the breakdown of undigested parts of fiber, can produce essential vitamins or regulate host immunity. Abnormalities in quantity, bacteria increase the amount of kilocalories absorbed, facilitate the deposition of adipose tissue, and also affect appetite. In turn, the desired microflora supports normal metabolic processes and regulates the intake of the right amount of kilocalories with meals.

So, how to take care of the correct intestinal microflora? It needs to be properly nourished with foods rich in dietary fiber. It is worth enriching the daily diet with oats, barley, peas, beans, apples, citrus or plantain, psyllium and inulin. As scientific studies show, the inclusion of 10 g of inulin in the daily diet contributes to a reduction in body weight and a decrease in body fat compared to the placebo group.

Another group of substances that affect the normal composition of the intestinal microflora are polyphenols. They are found in plant products and are mainly known for their antioxidant and anti-inflammatory effects. Together with the intestinal microbiota, they form a dependent duet. The most rich in these components are: berry fruits, cocoa, green and black tea, legumes, pomegranate, flaxseed and cereal products.

The described mechanisms and relationships show how complex the human body is and what impact a balanced diet has on every level. When we eat healthy and varied, we simultaneously support the intestinal microflora, and it affects the feeling of satiety, regulates glucose and reduces the desire to snack, which makes it easier for us to make healthy food choices.

Diseases that contribute to obesity

In addition to the genetic determinants of obesity, there are disease entities that, indirectly or directly, can make it difficult to maintain a normal body weight. Secondary obesity occurs in certain endocrine, genetic diseases or in diseases of the hypothalamus and pituitary gland. Weight problems are seen in people struggling with hypothyroidism, which can be the result of pituitary damage, Hashimoto's disease, or removal of the thyroid gland.

Another group of diseases are the units associated with the hypothalamus (the area in the brain), which is responsible for the secretion of hormones, the circadian rhythm or the feeling of hunger and satiety. Disorders in this area may be associated with excessive appetite and lack of satiety. Examples of such diseases are, for example, Prader-Willi, Bardet-Biedl syndrome. The problem of hyperphagia can appear with damage to the hypothalamus caused by radiotherapy or during surgical intervention.

Not only the disease individuals, but also the drug therapy used can affect the problem of feeling full or increased appetite. Among the drugs that increase the risk of accumulation of excess body fat, the following stand out: neuroleptics, antidepressants and antiepileptic drugs, tranquilizers, steroid hormones, beta-adrenergic, as well as antidiabetic drugs — insulin and some sulfonylurea derivatives. This does not mean that the listed medications should be discontinued, since they are prescribed as the primary treatment for certain diseases. When using the drug therapy indicated above, more attention should be paid to movement and dietary choices.

Environment and Obesity

Most often among children, adolescents and adults meets obesity is simple, that is, formed as a result of a positive energy balance. There is a belief that if mom is obese, the baby will definitely be too! Although the probability is high (80% - in the case of obese parents, and 40% when only one of the parents was obese), obesity is not mainly due to genes, but to the patterns of nutrition and lifestyle transmitted.

Of course, there is a hypothesis about the innate determinant of obesity - the theory of the sparing genotype, resulting from the adaptation of the body to store energy for a period when access to food will be limited. Such a metabolism was necessary in prehistoric times, when it was necessary to hunt game or pluck wild-growing fruits and shoots of plants, and the meal came once every few days/weeks. Nevertheless, it is currently difficult to determine how many primary genes are active in our genotypes and this information can be treated more as a curiosity.

We need to focus on what we have a real impact on.. The very first days in the womb are important for the metabolic health of the baby. As studies show, excessive mother's body weight, as well as improper nutrition during pregnancy, promotes the development of obesity in the child, the formation of insulin resistance or hypertension. Both too high and too low birth weight of an infant carry a high metabolic risk. Importantly, not only the amount, but also the type of products consumed by the pregnant woman affects the later taste preferences of the baby. The flavors of the products penetrate into the amniotic waters, the baby gets used to them and remembers them as pleasant and safe memories.

Then, during childhood, he is more willing to reach for them. As you can see, the formation of eating habits begins from the first days of life. Nutritional duplications that they observe among loved ones. At this stage, it is essential not to teach the regulation of emotions with food.

In addition to providing an excessive amount of calories in the development of obesity, physical activity has a huge impact. There are many solutions such as elevator, escalator, electric scooters that reduce our energy expenditure.

summary

Regardless of the cause of the resulting obesity, the condition of excess body fat is debilitating for our body. The treatment process should be taken as soon as possible, before the changes are irreversible. Treatment of obesity requires an interdisciplinary approach and multidirectional action. Many times, in addition to drug therapy and a balanced diet, the support of a psychologist or psychiatrist will be necessary. If you are struggling with excess weight and are heading towards obesity, try to stop this process as soon as possible. The most effective method of preventing obesity is a diet based on the correct principles of nutrition in combination with regular physical exertion. If a weight loss diet proves to be ineffective, the first step should be to verify its caloric content, pay attention to snacks, drinks drunk and look at physical activity. After that, it is worth doing basic research and nourishing the intestinal microflora. Only at the very end can you look for the cause in the genes, since the mutations described above occur quite rarely.

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