When talking about excess weight and obesity, most of us tend to imagine men and women in their 40s – with a "beer belly", a stomach that begins to sag and kilograms that gradually accumulate over the years. However, a large-scale Swedish study recently published challenges this perception: It is weight gain at a young age, already in the 20s, that carries the highest risk – and sometimes even more than the kilograms added at a later age.
The study followed more than 620 thousand participants over decades, with their weight measured at least three times between the ages of 17 and 60. The findings were unequivocal – those who developed obesity before the age of 30 showed about a 70% higher risk of premature mortality. Moreover, every additional kilogram gained per year at a young age was linked to an 18% increase in the risk of death from any cause among men and 16% among women. According to the study’s findings, participants gained an average of about 18 kilograms over the follow-up period, but the rate was not uniform. The fastest increase was recorded at younger ages, and was particularly prominent among men.
A cumulative effect over the years
Excess weight and obesity between the ages of 17 and 29 were linked to an increase in mortality from heart disease, type 2 diabetes, kidney disease and various types of cancer, with the strongest and most prominent association found with type 2 diabetes. In addition, particularly significant associations were found between substantial excess weight and obesity at a young age and high blood pressure and liver cancer among men, as well as uterine cancer among women.
According to the study findings, the risk does not depend only on the weight gain itself – but mainly on the length of time the body carries it. The more years a person lives with obesity, the more severe the cumulative impact on health becomes. Although weight gain at an older age is also linked to increased risk, the later it occurs in life, the lower the intensity of the risk. In other words, the most significant damage is that which is built and accumulated over years.
An additional unique finding emerged among women: Weight gain between the ages of 45 and 60 was linked to higher mortality rates from cancer, a different pattern from that found among men, in whom the most significant impact was recorded at a young age. That is, for women, the decade between 45 and 60 is also not a "safe zone" in terms of the risk of cancer morbidity.
These findings come against the background of a worrying global trend according to which the number of young people under the age of 25 with excess weight and obesity jumped from 198 million to 493 million people between the years 1990 and 2021. According to estimates, the numbers are even expected to reach 746 million by the year 2050, if no significant intervention is undertaken. The researchers conclude that the data reinforce the urgent need for early and consistent prevention strategies, not when the damage has already been established, but long before it begins to accumulate.
Dr. Raz Hagoel, Director of the Medical Center for the Treatment of Obesity: "The study reinforces what we have been witnessing for years – obesity is not just an aesthetic issue, but first and foremost a chronic disease that leads to the development of additional diseases. The earlier it begins, the more the damage to the blood vessels, the liver and the hormonal system deepens. What begins as excess weight in the twenties may later develop into type 2 diabetes, high blood pressure and even cancer. Therefore, not only the obesity itself but also the length of time the patient lives with it may cause cumulative damage. It is important to emphasize that today there are advanced therapeutic tools that enable medical intervention already at a young age, in order to reduce risks later in life and significantly improve overall health".