Author: healthy
Date: 10/16/2017
Researchers from the University of California, Davis, investigated and concluded that there is no inevitable link between being overweight and higher mortality risk. Over a six-year follow-up period, individuals who were overweight or obese did not show higher mortality risks compared to those with normal weight. Only severely obese individuals who also suffered from diabetes or hypertension faced elevated mortality risks. A report published on July 18 in The Journal of American Board of Family Medicine challenges previous studies. Earlier research, conducted when obesity was less common, linked higher short-term mortality with increased body weight. Anthony Jerant, professor of family and community medicine at the University of California, Davis, stated: 'Many people believe that any degree of overweight or obesity increases mortality risk, but our new findings contradict this belief. In our six-year study, we found only severely obese individuals with diabetes or hypertension faced higher mortality risks.' According to this study, Jerant advises doctors to inform overweight or obese individuals that obesity harms health but does not increase short-term mortality risk. Instead, doctors should warn severely obese individuals with diabetes or hypertension that their risk is higher and recommend corresponding treatments, such as weight loss. Jerant added: 'Overweight or obesity poses threats to personal or public health, but to avoid significantly affecting quality of life, we also recommend weight loss for obese individuals.' During the study, Jerant collected data from 2000 to 2005 across the United States, involving nearly 51,000 adults aged 18 to 90 years participating in the Medical Expenditure Panel Survey. This included health information such as diabetes or hypertension status. Participants were categorized by BMI: underweight (BMI < 18.5), normal weight (BMI 18.5–24.9), overweight (BMI 25–29.9), obese (BMI 30–34.9), and severely obese (BMI ≥ 35). Over six years, among 50,994 participants, nearly 3% — 1,683 — died. Researchers found that severely obese individuals had a 1.26 times higher mortality risk than those with normal weight. However, if they did not have diabetes or hypertension, overweight, obese, or severely obese individuals had mortality risks comparable to or even lower than those with normal weight. Meanwhile, underweight individuals — regardless of diabetes or hypertension — had mortality risks approximately twice that of normal-weight individuals, consistent with earlier studies. Over the past few decades, overweight and obesity have become increasingly common. About one-third of U.S. adults aged 20 and older are obese, and another third are overweight. Besides diabetes and hypertension, obesity is also linked to heart disease, osteoarthritis, and sleep apnea. The relationship between weight and mortality risk has long been controversial. Although some analyses of data from 30 years ago suggested that mortality risk increased with weight, recent studies — including this one — strongly challenge this assumption. Jerant noted that our study suggests the risks associated with BMI exceeding normal levels in modern times may have decreased compared to the past, though the exact reason remains uncertain. It is likely because as more overweight and obese individuals have been identified, doctors have become more attentive to complications such as hypertension, high cholesterol, and high blood sugar, enabling earlier detection and treatment. The six-year duration of the study is insufficient to establish a clear link between unhealthy weight and long-term mortality risk. However, we hope this study will stimulate further research to reassess the relationship between overweight/obesity and long-term mortality risk.