Overweight and obesity are risk factors for a range of diseases and early mortality. We talked about this in detail in our other articles (here, here). Based on this, it can be assumed that the thin live the longest.
But studies show that the longest-lived people are those who start adulthood at a normal weight and move to slightly overweight later in life, but who are never obese.
Adults in this weight category live longer than even those whose weight remains within the normal range throughout their lives. The norm is a weight approximately equal to:
- Height minus 100 – for men
- Height minus 110 – for women
A more accurate measure is the Body Mass Index. In order to find out your Body Mass Index, you need to divide your weight (in kilograms) by your height (in meters) squared. For example, if your weight is 80 kg and your height is 1,8 meters, then your Body Mass Index will be 24,7.
Body Mass Index = Weight / Height²
BMI = 80 / (1,8 * 1,8) = 80 / 3,24 = 24,7
Guidelines for Body Mass Index:
- under 18,5 – Low Body Mass Index
- 18,5–25 – Norm
- 25–30 – Overweight Body Mass Index
- 30 and above – Obesity
Those who start adulthood with obesity and continue to put on weight have the highest mortality rate.
The effect of weight gain on life expectancy is complex. It depends both on age and on the time and magnitude of weight gain.
The underlying message is that those who start at a normal weight in early adulthood, gain a small amount of weight throughout their lives, and enter the overweight category in later adulthood actually increase their life expectancy.
Worrying trends have been identified for the overweight and obese younger generation, who are more likely to be at risk of increased mortality associated with increased obesity later in life.
- Across generations, those who started at a normal weight and moved to overweight later in life, but never became obese, stand a good chance of living longer.
- Those who remain at a normal weight throughout their lives are in 2nd place in terms of life expectancy.
- They are followed by those who are overweight, which subsequently remains stable.
- This is followed by those who have a low Body Mass Index and keep it stable.
- In the older generation, those who were overweight but lost weight are next on the list of life expectancy.
- In the worst position are those who started with obesity and continue to gain weight.
Based on scientific data, it can be assumed that people who were slightly overweight at age 50, but maintain their weight relatively stable, are most likely to survive for the next 20 years.
In other words, slightly overweight adults without signs of obesity (with a Body Mass Index in the range of 25-30) have the maximum chances for longevity.