New research has been published by the Mayo Clinic, and it is currently making the rounds on the internet in major news channels.
It’s not often that something so scholarly enters popular conversation, but the study – Healthy Lifestyle Characteristics and Their Joint Association With Cardiovascular Disease Biomarkers in US Adults – is making headlines in part due to its scathing takeaway: that less than 3 percent of Americans live a “healthy lifestyle.”
According to the research published in the journal Mayo Clinic Proceedings, only 2.7% of American adults in the study were found to exhibit four fundamental healthy lifestyle characteristics. These four were:
While few people will be surprised that these healthy lifestyle characteristics have positive effects on overall health in general, this study has another very interesting, yet less sexy/headline-making conclusion:
Although multiple healthy lifestyle factors are important, specific health characteristics may be more important for particular cardiovascular disease risk factors.
Which specific health characteristic may be more important? When it comes to cholesterol levels, the study suggests that simply having a healthy body fat percentage, even if other healthy lifestyle factors aren’t always followed, can have a significant effect on HDL-C levels (the “good cholesterol”) and reducing overall total cholesterol.
For the purpose of this study, researchers defined a “healthy” body fat percentage with a pretty wide range. For men, the healthy range was set from 5% - 20%; for women, the range was 8% - 30%.
These ranges essentially amount to as: “as low as can be achieved without causing negative health consequences and as high as what’s generally considered to be an upper acceptable limit before metabolic conditions may begin to occur”.
The researchers found that subjects that had a healthy body fat percentage plus any 1 other healthy lifestyle factor had increased HDL-C levels by 14.0 mg/dL.
Increased HDL is good for your body, as it helps to sweep up smaller bits of cholesterol – LDL – which it carries back into the liver for processing. Increased amounts of total cholesterol can cause buildup in your body’s arteries, which can increase the risk of heart disease or having a stroke.
What’s very interesting, however, is that the researchers also found that a healthy body fat percentage without ANY other of the three lifestyle factors also had favorable increases in HDL: 10.8 mg/dL when compared to people whose body fat percentages were “unhealthy.”
The difference between the groups with and without additional health characteristics other than body fat percentage, 3.2 mg/dL, was not considered significant by the researchers, leading them to conclude:
This relatively small estimated difference (14.0 vs 10.8 mg/dL) suggests that among the health behaviors in this study, normal body fat percentage may be one of the strongest correlates of HDL-C.
The findings didn’t stop at HDL. In terms of overall cholesterol, researchers found that total cholesterol for all types was reduced by 20.8 mg/dL for people who had a healthy body fat percentage plus any other healthy characteristic.
What about people who only had healthy body fat percentages? Total cholesterol levels were reduced by 19.3 mg/dL, seemingly isolating body fat percentage as the underlying factor behind positive changes in cholesterol.
Furthermore, in addition to increased HDL levels, a healthy body fat percentage was also positively associated with 9 other biomarkers including reduced fasting LDL, fasting triglycerides, fasting glucose, and insulin levels: all which are associated with reduced health risks.
While the health risks of obesity have been long understood and well-studied by doctors, physicians, and researchers, few studies have been able to effectively isolate and pinpoint actual health consequences associated with a particular body fat percentage range.
The extreme low end of the body fat percentage ranges used in this study were quite low – 5% and 8% for men and women respectively, percentages typically achieved only by professional bodybuilders and athletes – but the upper end of the ranges – 20% and 30% - are fairly uniform upper limits, and correspond with those recommended by the American Council on Exercise and The American College of Sports Medicine.
The research appears to suggest that maintaining a healthy body composition – as defined by a healthy body fat percentage that does not exceed 20% for men and 30% for women – can decrease the risk of cardiovascular disease due to the promotion of good cholesterol while helping to reduce other harmful health factors.
Although it’s always been a good idea to know your body fat percentage and have your body composition determined from time to time, in light of this study, it may be something you want to give more attention to, given its apparent effect on reducing your chances negative health risks.
The study is currently available in its entirety online, which you can access on the Mayo Clinic Proceedings website.