The first cause of excess weight reduction becomes energy consumption. Scientists estimate that with each decade person consumes 10% less energy, but a diet with almost no changes. It's not even for the fact that it starts to move less, the body itself is changed - slows metabolism, reduces the activity of the cardiovascular system, respiratory system. Therefore, with each decade of a person's weight increases on average by 10%.
The second reason becomes hormonal changes that occur in the body. In women, weight gain often associated with pregnancy and childbirth, infant feeding period. The risk of excess weight is very high and during menopausal changes in both women and men.
Paying less attention to the third reason, but it exists. It is a psychological reason. 30 years old man lives in active search of his place in life, this period is associated with anxiety and fervor of youth. After 30 years, people settle down - it usually is adjusted personal life, have a family, a permanent job and measured way of life. This reduces the monotony of tone and physical activity, which leads to a calm and, consequently, to weight gain.
Become the fourth leading cause physiological characteristics of the human body. If a young man he loses weight from stress, as produced in this adrenaline destroys cells and tissues, after 35 years of adrenaline the body is no longer able to produce on their own and begins to produce the hormone insulin, which contribute to an increase in fat mass. After 40 years, any stress only promotes intensive weight gain.
If you consider all these factors and adjust your diet, control costs and energy consumption, with the help of physical activity, the risk of obesity can be significantly reduced, if not avoid weight gain over the years.