According to a new study in the journal Pediatrics, neck circumference could be used to help calculate body fat, CNN reports. Health experts complain that body mass index, which measures weight relative to height, isn’t accurate enough since athletes or muscular people might be classified as obese, while it also underestimates body fat in older people. But a wide neck circumference is associated with obesity-related conditions like sleep apnea, diabetes and hypertension, and is being looked at as a flag for obesity and heart problems. In the study, lead author Dr. Olubukola Nafiu and his team looked at 1,102 children, taking measurements for height, weight and neck circumference. Neck was measured with a bendable tape at the most prominent part of the neck (the Adam’s apple in older males). A six-year-old boy with a neck circumference greater than 11.2 inches was 3.6 times more likely to be overweight or obese, they found.