Women with varying body shapes

Your body, including height and weight, can reveal many clues about your health. A higher BMI (body mass index), or weight to height ratio, is associated with higher risk for developing certain diseases and conditions, most of which occur more often in people who have a higher percentage of body fat relative to lean muscle mass (via National Heart, Lung, and Blood Institute). However, your BMI does not tell the whole story.

First, BMI does not take into account how much of your weight might be comprised of fat versus muscle versus bone (i.e., frame size), which has been deemed relevant in other measures of healthiness of weight, according to Harvard Health Blog. Second, your body mass index does not take into account how your body weight is distributed throughout your body. Scientists study body shape because it can help fill in some of these blanks (via Penn Medicine).

The study of body shape is focused primarily on your "build," which is determined largely by genetics. Although your build doesn’t change based on diet and exercise, it can help you determine how best to care for yourself. Here are some of the surprising things your body shape can reveal about your health.

What’s your somatotype?

different body shapes

The "somatotype" system for classifying body types was devised by Dr. William H. Sheldon back in the 1940s, according to the University of Houston. The somatotype theory places all human bodies into one of three general categories: ectomorph (which tends to be on the thinner side), endomorph (which tends to be on the thicker side) and mesomorph (which tends to be more muscular). According to Dr. Sheldon, body type is genetic, and it is no more possible to change your body type than it is to change your height (once you’re fully grown).

Although this system is just one way of classifying the general shape and structure of human bodies, it is one of the most well known. What many people don’t know about the somatotype system, however, is that Dr. Sheldon devised it to support his psychological theories relating to criminology, as opposed to as a way of optimizing health or diagnosing health problems (via Britannica). Dr. Sheldon’s research attempted to predict one’s propensity toward committing certain crimes. The scientific community has discredited the somatotype theory’s usefulness in criminology, but the body types identified by Sheldon still carry weight.

Those with an ectomorphic body shape may have trouble putting on weight and muscle

One of the three general somatotypes identified by Dr. William Sheldon is the ectomorphic body type, or the "ectomorph," according to the University of Houston. An ectomorph is someone with a longer, leaner build. Think: celebrities like Kate Middleton and Jeff Goldblum. Their bones, alone, are more slender than others of the same height. Although ectomorphs tend to be thin and lanky, they are nevertheless capable of gaining body fat and actually often have a higher body fat percentage than one might assume just by looking at them, according to registered dietitians Tiffani Bachus and Erin Macdonald. They explained in an article for Ace Fitness that "the best diet for an ectomorph is one that is higher in carbohydrates and calories."

Specifically, the ectomorph’s diet should include about 50 to 60 percent of calories from carbohydrates, 25 percent from fat, and 25 percent from protein. Because an ectomorph’s metabolism tends to be faster than other body types, they may have trouble putting on weight and muscle (via Ace Fitness). Ectomorphs may need to eat more than just three meals a day, according to the University of Houston. However, this may change as an ectomorph ages.