Is There Really an "Obesity Paradox", With Fat Linked to Longer Life? | By Benjamin Ryan | Virtually Modern Medicine
A controversy has been brewing among research scientists of late as to whether there is in fact a so-called “obesity paradox.” Recent studies have found those who are overweight apparently have a similar lifespanor in fact live longer than those with a normal body mass index (BMI).
Seeking to address this controversy, a team of investigators from Northwestern University and the University of Texas amassed a remarkablyenormous pool of data on individuals’ BMI and their ultimate longevity and cardiovascular health, covering a 50-year period. The scientists’ conclusion was that no, the obesity paradox is not actually a thing. According to their analysis, overweight individuals (with a BMI between 25 and 29.9), lived about the same length as those with a normal weight (BMI between 18.5 and 24.9). However—and this is key—the heavier individuals lived more of that time burdened by cardiovascular disease. This likely meant they had a lower quality of life and cost the U.S. health care system more money.BMI is calculated by dividing bodyweight by height. The tool can be crude since it cannot account for variations in muscle mass compared with body fat. For example, a gym rat with considerable muscle and low body fat may have a BMI that erroneously supposes he is overweight. Additionally, the BMI calculation cannot determine how body fat is distributed, in particular if it is gathered around the midsection in a “beer gut,” a phenomenon associated with various health risks.
You can easily calculate your BMI by entering your weight and height into a formula at the following website https://www.nhlbi.nih.gov/health/educational/lose_wt/BMI/bmicalc.htm. In addition, here’s a link to look at definitions of overweight and obesity based on BMI https://www.cdc.gov/obesity/adult/defining.html.
Publishing their findings in JAMA Cardiology, the research team pooled data from 10 cohort studies, which included nearly 191,000 in-person examinations of individuals who were between 20 and 79 years of age and did not initially have clinical cardiovascular disease. All told, the study had data on 3.2 million years of follow-up, with at least 10 years on each individual, spanning 1964 to 2015. About 12 percent of the pooled cohort was African American and 74 percent was female. The average age was 46 years among men and 59 among women. Just 0.3 percent of the cohort was underweight (a BMI below 18.5) and 6.6 percent was morbidly obese (a BMI of at least 40) at the first study visit. About two thirds had a normal body weight or were overweight. Those who had a normal bodyweight and who were overweight lived about the same length of time. Meanwhile, obese individuals, compared with those with a normal BMI, had shorter lifespans. The heavier individuals, including those who were overweight and those who were obese, had a greater risk of developing cardiovascular disease at an earlier age compared with those in the normal BMI range, which meant they spent more of their lives saddled with related health problems.
Among middle-aged individuals, compared with those with a normal BMI, those who were overweight upon their first examination were 1.2-fold (among men) and 1.3 fold (among women) more likely to be diagnosed with cardiovascular disease during the study’s follow-up period. For those who were obese at the study’s baseline, the corresponding respective figures were a 1.7-fold and 1.9-fold increased risk for men and women. And for the morbidly obese the corresponding respective figures were a 3.1-fold and 2.5-fold increased risk for men and women. When it came to the diagnosis of specific cardiovascular subtypes, having a higher BMI was mostly strongly associated with heart failure.
The study is limited by the fact that it did not account for changes in BMI during follow-up. However, other studies have recently indicated that BMI tends to follow a predicable upwards trajectory from young adulthood to middle age, regardless of initial BMI. (Translation: We tend to put on pounds as we age.)
Sources:
(1) https://www.eurekalert.org/pub_releases/2018-02/jn-ioa022618.php; (2) https://jamanetwork.com/journals/jamacardiology/article-abstract/2673289?redirect=true
#Obesity #Lifespan #CardiovascularDisease #VMM #Pharmative
A controversy has been brewing among research scientists of late as to whether there is in fact a so-called “obesity paradox.” Recent studies have found those who are overweight apparently have a similar lifespanor in fact live longer than those with a normal body mass index (BMI).
Seeking to address this controversy, a team of investigators from Northwestern University and the University of Texas amassed a remarkablyenormous pool of data on individuals’ BMI and their ultimate longevity and cardiovascular health, covering a 50-year period. The scientists’ conclusion was that no, the obesity paradox is not actually a thing. According to their analysis, overweight individuals (with a BMI between 25 and 29.9), lived about the same length as those with a normal weight (BMI between 18.5 and 24.9). However—and this is key—the heavier individuals lived more of that time burdened by cardiovascular disease. This likely meant they had a lower quality of life and cost the U.S. health care system more money.BMI is calculated by dividing bodyweight by height. The tool can be crude since it cannot account for variations in muscle mass compared with body fat. For example, a gym rat with considerable muscle and low body fat may have a BMI that erroneously supposes he is overweight. Additionally, the BMI calculation cannot determine how body fat is distributed, in particular if it is gathered around the midsection in a “beer gut,” a phenomenon associated with various health risks.
You can easily calculate your BMI by entering your weight and height into a formula at the following website https://www.nhlbi.nih.gov/health/educational/lose_wt/BMI/bmicalc.htm. In addition, here’s a link to look at definitions of overweight and obesity based on BMI https://www.cdc.gov/obesity/adult/defining.html.
Publishing their findings in JAMA Cardiology, the research team pooled data from 10 cohort studies, which included nearly 191,000 in-person examinations of individuals who were between 20 and 79 years of age and did not initially have clinical cardiovascular disease. All told, the study had data on 3.2 million years of follow-up, with at least 10 years on each individual, spanning 1964 to 2015. About 12 percent of the pooled cohort was African American and 74 percent was female. The average age was 46 years among men and 59 among women. Just 0.3 percent of the cohort was underweight (a BMI below 18.5) and 6.6 percent was morbidly obese (a BMI of at least 40) at the first study visit. About two thirds had a normal body weight or were overweight. Those who had a normal bodyweight and who were overweight lived about the same length of time. Meanwhile, obese individuals, compared with those with a normal BMI, had shorter lifespans. The heavier individuals, including those who were overweight and those who were obese, had a greater risk of developing cardiovascular disease at an earlier age compared with those in the normal BMI range, which meant they spent more of their lives saddled with related health problems.
Among middle-aged individuals, compared with those with a normal BMI, those who were overweight upon their first examination were 1.2-fold (among men) and 1.3 fold (among women) more likely to be diagnosed with cardiovascular disease during the study’s follow-up period. For those who were obese at the study’s baseline, the corresponding respective figures were a 1.7-fold and 1.9-fold increased risk for men and women. And for the morbidly obese the corresponding respective figures were a 3.1-fold and 2.5-fold increased risk for men and women. When it came to the diagnosis of specific cardiovascular subtypes, having a higher BMI was mostly strongly associated with heart failure.
The study is limited by the fact that it did not account for changes in BMI during follow-up. However, other studies have recently indicated that BMI tends to follow a predicable upwards trajectory from young adulthood to middle age, regardless of initial BMI. (Translation: We tend to put on pounds as we age.)
Sources:
(1) https://www.eurekalert.org/pub_releases/2018-02/jn-ioa022618.php; (2) https://jamanetwork.com/journals/jamacardiology/article-abstract/2673289?redirect=true
#Obesity #Lifespan #CardiovascularDisease #VMM #Pharmative