In a groundbreaking study conducted by researchers from the School of Public Health at Tel Aviv University’s Faculty of Medicine, it has been revealed that a significant number of individuals with normal weight may actually be obese based on their body fat percentage. This revelation challenges the widely used Body Mass Index (BMI) measurement, suggesting that it may not be as sensitive in defining obesity as previously believed. The findings of this study emphasize the importance of considering body fat percentage as a more reliable indicator of overall health and cardiometabolic risk.
Reconsidering Obesity Metrics: The Shortcomings of BMI
The study, the largest of its kind ever conducted in Israel, was led by Prof. Yftach Gepner and PhD student Yair Lahav, along with Aviv Kfir, and was based on data from the Yair Lahav Nutrition Center in Tel Aviv. Traditionally, BMI has been considered a standard indicator of an individual’s general health, using weight and height measures. However, the research team discovered a significant disparity between BMI and body fat percentage in determining obesity.
The phenomenon, known as “the paradox of obesity with normal weight,” highlights the existence of individuals with normal BMI scores who actually possess a higher-than-normal body fat percentage. This condition places them at risk for various life-threatening cardiometabolic diseases such as heart disease, diabetes, fatty liver, and kidney dysfunction. The prevalence of this phenomenon in Israel’s adult population was studied, with approximately one third of the participants, or 1,000 individuals, falling within the normal weight range. Among these participants, 38.5% of the women and 26.5% of the men were identified as “obese with normal weight” due to their excessive body fat content.
Moreover, the study revealed that these individuals, despite having normal BMI scores, often go unnoticed by healthcare providers and receive no treatment or guidance to improve their nutrition or lifestyle. This lack of identification puts them at even greater risk for developing cardiometabolic diseases.
A New Gold Standard: Emphasizing Body Fat Percentage
The research team strongly advocates using body fat percentage as a more reliable indicator of an individual’s general health than the conventional BMI measurement. To support their recommendation, they analyzed the anthropometric data of 3,000 Israeli women and men, incorporating BMI scores, DXA scans (which measure body composition, including fat content), and cardiometabolic blood markers.
The study demonstrated a significant correlation between “obesity with normal weight” and elevated levels of sugar, fat, and cholesterol – major risk factors for cardiometabolic diseases. Additionally, the researchers found that 30% of the men and 10% of the women identified as overweight based on BMI actually had a normal body fat percentage, further reinforcing the limitations of BMI as an accurate measure of obesity.
To address this issue, the researchers propose equipping clinics with suitable devices to measure body fat content, making it the gold standard for assessing an individual’s health and cardiometabolic risk. Two convenient and accessible tools for this purpose include skinfold measurements, which estimate body fat based on the thickness of the fat layer under the skin, and a user-friendly device that measures the body’s electrical conductivity, commonly used in fitness centers.
In conclusion, this groundbreaking study highlights the prevalence of “obesity with normal weight” and urges the adoption of body fat percentage as a superior indicator of an individual’s general health. By recognizing this “paradox of obesity with normal weight” and implementing suitable tools for measuring body fat content, healthcare providers can take crucial steps to prevent disease and early mortality in individuals at risk. The researchers’ recommendation to make body fat percentage the prevailing standard of health has significant implications for healthcare systems not only in Israel but also worldwide.
