14/02/2022 # Home
Body type eating: Is it pseudoscience? Or the real deal? And should you care?
By Helen Kollias, PhD, and Ryan Andrews, MS, RD
Nutrition science is notoriously confusing, which invariably leads to debates about what works—and what doesn’t.
One of the most heavily debated nutrition topics in our community? Eating for your somatotype, or body type. (“Soma” is Greek for “body”.)
People tend to fall into one of two categories on this subject.
- They place way too much importance on body typing.
- They dismiss body type as complete pseudoscience.
On both sides of the debate, we’ve also found that people buy into myths, such as:
“Everyone should eat according to their body type.”
“No legitimate scientist would ever use body typing.”
Like so many hotly-contested topics, the truth lies between the two extremes.
Here’s the truth: For most people, body type eating isn’t necessary or important.
For them it’s just not the most effective tool for their needs and goals.
So why bother discussing it?
Because this is also true: Based on our work with more than 100,000 clients, we’ve discovered that body type eating can benefit some people in a couple of highly specific situations. This is especially true when foundational nutritional strategies aren’t enough to get these individuals all the way to the finish line.
In this article, we’ll explain:
- the origins of body typing
- what science reveals about body typing
- how to know if a body type diet is right for you
- how to try body type eating for yourself (if desired or appropriate)
You’ve probably heard about three body types. What you may not know: countless types exist.
In the 1940s, psychologist Dr. William Sheldon came up with the idea of somatotypes. (In case you missed it earlier in the article, somatotype is just another word for body type).
Originally, Sheldon thought body size and shape helped to determine personality traits such as assertiveness, aggressiveness, shyness, and sensitivity.
He was wrong.
But his three main body type classifications (endomorph, mesomorph, and ectomorph) live on, though they’ve evolved—for the better.
According to Sheldon’s definitions:
Ectomorphs were thin, narrow, delicate, fragile, linear, and poorly muscled.
Endomorphs were soft, round, pudgy, and overweight.
Mesomorphs were broad-shouldered, narrow in the waist and hips, muscular, compact, and athletic.
Sheldon determined those types based only on height and weight, and front, side, and back photos (known as photoscopy). But other scientists soon rightly criticized this method as unreliable and subjective—because it was.
Eventually, Barbara Honeyman Heath Roll and Lindsay Carter developed the currently used method for evaluating body type. It assesses and scores body type based on 10 distinct measurements. According to their method:
Endomorphy is relative fatness or leanness as determined by the sum of three skinfolds taken at the triceps, subscapular, and suprailiac. The higher the sum of these folds, the higher the endomorphy score.
Mesomorphy is muscle mass relative to height. It’s determined by the width of the elbow and knee, flexed arm circumference corrected with triceps skinfold, and calf circumference corrected with medial calf skinfold.
Ectomorphy is the lack of body mass (body fat and muscle mass) relative to height and is determined using someone’s height and weight.
Once calculated, these values are plotted on a tri-axial graph to determine a person’s somatotype.
Compared to Sheldon’s approach, the Heath-Carter method more closely resembles a body composition measurement, providing a more accurate description of a person’s ratio of fat to muscle to bone.
It also allows for a wider variety of body types, such as mesomorphic ectomorphs or endomorphic ectomorphs (what some people refer to as skinny-fat). As you can see on the graph below, the typical gymnast might be more mesomorphic and the typical sumo wrestler more endomorphic, but neither falls 100 percent into one category or the other.
So despite what many think, the Heath-Carter method is actually highly individualized. Still, even though nearly everyone is a mix of body types, most folks can find their general tendencies in one of the three groups.
And no matter which group someone resembles, they’re not stuck. They can change their body type. For instance, bodybuilders mistaken for “natural” mesomorphs may actually be endomorphs who’ve trained and dieted hard. Or they could also be ectomorphs who’ve spent years guzzling protein shakes and lifting weights.
Your body type is not a life sentence.
Somatotype describes body components like fat mass, lean mass (muscle), and the ratio between the two—not unlike measuring someone’s body composition. That’s why, over the years, somatotype has become an assessment tool for medical professionals and researchers, similar to body mass index (BMI). While neither is a perfect system, both BMI and somatotype are simpler and more affordable than other measurement tools, which makes them accessible to more people.
That’s why, just as BMI can change over time, so can body type.
It’s just a tool used to describe someone’s body. That’s it. Like BMI, body typing gives you an idea of whether someone who is 200 pounds and 5’10” is obese, very muscular, or somewhere in between, which can be valuable in a clinical or coaching setting. It helps you to know, for example, how someone’s body is truly affecting their health.
Over the years, researchers have tested whether somatotypes correlate to other measures or traits. So for example, researchers have looked into questions like:
Is there an association between somatotypes and personality? Sorry Dr. Sheldon, but no. As it turns out, people with ectomorphic bodies are not the only ones who feel self-conscious. Similarly people with mesomorphic body types don’t necessarily take more risks than people with other body types. In other words, we all have a body and we all have a personality, but our bodies do not necessarily influence our personalities and vice versa.
Is there an association between somatotypes and genetics? Yes. Based on studies that looked at identical twins, we know that mesomorphy and ectomorphy are both highly linked to genetics (both about 70 percent) while endomorphy is much lower (30 percent). For a comparison, height has a heritability of about 80 percent.
Is there an association between somatotypes and athletic performance? Yes. Research has linked somatotypes with the fast-twitch muscle variation of ACTN3, the only gene associated with power athletes. Mesomorphs are more likely to have this “fast” gene than other body types, which may explain why sprinters tend to fall into the mesomorphic body type. Elite marathon runners tend to be ectomorphs while elite sumo wrestlers are usually more endomorphic.
Is there an association between somatotypes and cardiovascular disease? Yes. Because of this, you may be more or less likely to develop high blood pressure, elevated cholesterol, and other heart disease risk factors. Here’s why. Fat and muscle both serve as endocrine organs that produce hormones and proteins. Fat makes substances called adipokines, and skeletal muscle makes myokines. A recent study suggests that these substances regulate high blood pressure (hypertension) reciprocally. Overall, myokines (from muscle tissue) seem to decrease hypertension while adipokines (from fat tissue) increase it.
Reference – Precision Nutrition’s Published Lesson Plan Articles