On Monday, I explained how something as simple as 20 minutes of exercise per day could cut your risk of cancer by as much as 42 percent.
Today, I’m going to switch gears ever so slightly, and tell you about another simple way to extend your life. And that’s simply watching your weight.
Now, before I get started, let me say that I’m not a big fan of relying solely on BMI to assess your proper weight. (It simply doesn’t account for differences in body composition the way it should.)
Nevertheless, it’s the standard we’re working with right now. And, despite its drawbacks, it’s not completely useless.
In fact, there are not one, but three new studies demonstrating the strong connection between BMI and risk of early death.
Let’s take a look…
The first study, published in the British Medical Journal, examined the relationship between lifetime body size and mortality. Researchers looked at data on more than 116,000 men and women from the Nurses’ Health Study and the Health Professionals Follow-up Study.
Participants recalled their body shapes at age 5, 10, 20, 30, and 40. They also gave their BMI at the age of 50. Researchers followed them for 15 years from age 60 on to collect data on both all-cause and cause-specific mortality.
Subjects who were lean their entire lives enjoyed significantly lower death rates. By contrast, a lifetime of being heavy was linked with higher mortality. This was particularly true if weight increased in middle age
The second study also appeared recently in the BMJ. And this one claims to have found the “optimal” BMI for the longest lifespan.
Researchers analyzed more than 200 studies, including nearly 30 million subjects.
Results showed the lowest death rates in non-smoking subjects whose BMIs ranged between 20 and 25. (Needless to say, smoking is and always will be a deal breaker, regardless of your weight.)
Finally, there was a third analysis — this one, featured in the Journal of the American Medical Association — which looked at data from a group of Danish participants.
Interestingly, this study found that the BMI associated with the lowest mortality rates has actually creeped up over the last 40 years — from 23.7 to 27. (Overweight by current standards, but still not obese.)
My guess is that there’s a two-fold explanation for this. On one hand, you simply have more people in a higher BMI class nowadays, so it’s harder to find subjects in the low 20s on the BMI scale to begin with. And on on the other hand, without question, treatment has improved over the same time frame. So you can take this conclusion for what it’s worth.
These studies may differ slightly in the details. But when you get right down to it, they all share a common conclusion: Staying lean and fit will keep you alive longer.
Believe me, I know it’s not always easy. But you must stay consistent. And never simply assume that gaining weight is just a normal part of aging. Because it is most definitely not.