Why BMI Alone Isn’t Enough
BMI has long been used to estimate body fat based on height and weight. However, it has notable limitations. Experts, including Dr. Ahmed Elbediwy and Dr. Nadine Wehida from Kingston University, point out in a piece written for The Conversation that BMI cannot distinguish between muscle and fat, nor can it indicate where fat is stored in the body. For example, a competitive bodybuilder may have a high BMI but is not obese. In such cases, neck circumference offers an additional perspective, revealing the presence of visceral fat stored in the upper body.
This upper-body fat is particularly concerning because it is metabolically active. It releases fatty acids, hormones, and inflammatory substances into the bloodstream, which can disrupt normal bodily functions, increase chronic inflammation, and drive insulin resistance. Over time, this places strain on organs and raises the likelihood of serious complications.
Links to Cardiovascular and Metabolic Health
Research has consistently linked larger neck measurements to a higher risk of type 2 and gestational diabetes. Multiple studies, including reports cited by the New York Post, have also associated neck size with key cardiovascular risk factors, such as high blood pressure, low HDL (“good”) cholesterol, and elevated triglycerides.Additionally, larger neck circumference has been connected to atrial fibrillation, a condition that causes irregular heartbeat and increases the risk of stroke, blood clots, and heart failure. These findings persist even when adjusting for BMI, waist circumference, height, and weight, although the risk appears particularly pronounced in individuals with obesity.
Beyond metabolic and cardiovascular concerns, a thicker neck has been linked to obstructive sleep apnea, a condition characterized by repeated breathing interruptions during sleep. This disorder can cause severe daytime fatigue and further strain the heart. Some studies have also found correlations with erectile dysfunction in men.
Measuring Your Neck
Experts advise that neck circumference should not replace routine health check-ups but can serve as a useful additional tool. Generally, a neck measurement above 17 inches (43 cm) in men or 15.5 inches (35.5 cm) in women is considered large. Measuring is straightforward: wrap a tape measure around the narrowest part of the neck, keeping it snug but not tight.
Monitoring neck size can help individuals better understand their health risks and take preventive action through lifestyle changes such as cardiovascular exercise, weight training, improved sleep, and a balanced diet.