BMI is a commonly used metric that's supposed to tell you if you're at a healthy weight or not. As this illustration created from scans of real people shows, however, BMI can be very misleading.
The six people in the illustration are all 5 feet 9 inches (175cm) tall and weigh 172 pounds (78kg), which means they have the same BMI or body mass index (calculated by dividing your weight by your height). Technically each would be considered overweight based on their BMI of 25.4, but some obviously appear more fit than the ones with more abdominal fat, which has been linked to increased risk of health problems.
As we've mentioned before, BMI can be misleading. The New York Times explains that since BMI only factors in height and weight, it doesn't account for muscle or bone density and where a person carries weight.
BMI can be a useful measurement if it goes above 30, the threshhold for obesity, but overall, body fat percentage and body composition are more important health indicators than weight alone.
Same B.M.I., Very Different Beach Body [The New York Times]