Comments and Key points from this article on healthiest BMI
This article on Body Mass Index (BMI) had a key point: "The estimated nadir of the BMI curve was at 27.3 kg/m2." This means, the lowest mortality occurs at this BMI of 27.3.
Yes, it is true, and a closer inspection reveals more. Other studies have also found elevated mortality with low BMI1,2, and lowest mortality around the median BMI levels.
The article showed a graphic like the one below, but I have relabelled fat mass indicator as "fat" and fat-free mass indicator as "muscle" ( to make the graph easier to understand).
The graph shows that health hazard ( risk of death ) increases as fat increases.
Notice the body mass index has "U-shaped" curve that has its lowest risk at 27.3 kg/m2.
As you can see, increasing your muscle mass (by fitness, exercise, weight-lifting, etc) is the most effective way to become healthier. Dieting to reduce fat isn’t as effective.
- Kalmijn S, Curb JD, Rodriguez BL, Yano K, Abbott RD. The association of body weight and anthropometry with mortality in elderly men: the Honolulu Heart Program. Int J Obes Relat Metab Disord 1999 Apr;23(4):395-402
- Heitmann BL, Erikson H, Ellsinger BM, Mikkelsen KL, Larsson B. Mortality associated with body fat, fat-free mass and body mass index among 60-year-old swedish men-a 22-year follow-up. The study of men born in 1913. Int J Obes Relat Metab Disord 2000 Jan;24(1):33-7
2014 update. In December 2014, while applying new styling onto these webpages, I found a more recent article on this topic, and here it is. It’s for people age 51 or older.
This New article about Obesity and Mortality risk, using body mass index trajectories
There’s a very interesting quote in that new abstract.
“People in the overweight stable trajectory had the highest survival rate“
Reference: Zheng H, Tumin D, Qian Z, Obesity and mortality risk: new findings from body mass index trajectories. Am J Epidemiol, 2013; 178:1591-9
Here are the charts from the study. First is showing the 2 healthiest categories, called “overweight stable” and “overweight obesity”, colors red and blue.
Next shown is the actual survival curves. Notice red and blue lines have highest survival.
Another cool quote from the article:
“People who were overweight at 51 years of age and remained overweight through age 77 years had the lowest mortality risk.”
Baseline (at age 51) Normal weight, overweight and class 1 obesity (BMI 18.5 through 34.9) were not associated with significant increases in mortality risk.”
But don’t think that weight gain is harmless. It isn’t. IF you continue to have weight gain after age 51, in a faster upward trajectory than average, then it does lower future survival.
Another fun fact. The average man at age 51 is weight 184 pounds, height of 70 inches, and has a BMI of 26.6. The average woman at age 51 is weight 155 pounds and height 64 inches with a BMI of 26.6. So Both men and women with average BMI of 26.6 that is extremely close to the healthiest BMI of 27.3 ? Is that a coincidence? Maybe it’s Nature. Maybe what happens to our weight as we age, is inherited genes at work, and our population’s weight average is showing biologic wisdom.