Intermittent Fasting According to Your Body Type: Fact or Fiction?

I have been seeing ads online that try to get you to take a test to find out the best type of intermittent fasting according to your body type. I thought the whole concept seemed rather silly, but as I was looking for blog post ideas, I found that people are curious about this. What is intermittent fasting according to your body type all about? How can you practice intermittent fasting according to your body type and does it help?

What It Mean to Eat for Your Body Type

The idea behind intermittent fasting according to your body type is that your body type, or somatotype, gives you clues about your genes, your metabolism, and your hormonal function. It’s kind of like eating for your blood type, which you may have heard about. Some of us do better with more carbs, others more protein or more fats.

Eating According to Your Body Type: Fact or Fiction?

When it comes to eating according to your body type, people tend to divide into two groups:

  • Those who put too much emphasis on body typing.
  • Those who dismiss body typing completely.

In truth, there isn’t a lot of research to support the idea that you can eat according to your body type. However, there is some research to suggest that those who are long and lean (ectomorph) tend to have less muscle mass than those with an hourglass shape (or mesomorph). Another paper, in Anthropological Review, found that your body type may impact your body mass index, your dieting, and your overall health.

In theory, you could apply some of these concepts to intermittent fasting. Let’s try to look at intermittent fasting according to your body type with an open mind while using common sense and logic to avoid falling into the pseudoscience trap.

What is Your Body Type?

There are three main different body types: ectomorph, endomorph, and mesomorph. These somatotypes are the result of the work of psychologist Dr. William Sheldon. In the 1940s, he came up with the idea that body shape and size could help determine personality traits such as assertiveness, aggressiveness, shyness, and sensitivity. His theory was debunked, but his body types lived on, albeit with some modifications and additions.


The main feature of an ectomorph body type is a body that is thin, narrow, delicate, fragile, linear, and poorly muscled. People who fit in the ectomorph category have a fast metabolism and struggle to gain muscle. They tend to have a small frame, small joints, long arms and legs, and narrow shoulders. When they do build muscle, their musculature tends to be long and slim.


According to Sheldon, this body type was soft, round, pudgy, and overweight. Now, we mostly describe women with this body type as curvy and men as stocky. People in this category tend to gain weight easier, mostly around the belly, hips, and thighs. They have a short neck with high and square shoulders.


The mesomorph body type is kind of like the in-between type. People who are mesomorph have a medium-sized frame and tend to build muscle easily. They carry more muscle than fat (contrary to the endomorph type). They are not overweight and not underweight. Their weight distribution is fairly even. They have wide shoulders, thick forerams, large hands, wrists, and fingers.

How to Fast According to Your Body Type

Now, the questions is how can you practice intermittent fasting according to your body type? Does it even matter? I am going to be honest with you, I really don’t think it matters much. Your body type is just a general image of what your body looks like at the present time. It’s not a life sentence! However, I can share some insights on how your current body type can impact your fasting experience and how you can achieve the best results depending on your body type.

Intermittent Fasting According to the Ectomorph Body Type

The body type that describes you best is the endomorph type, it’s a good idea to not fast too much. The last thing you want is to lose more weight, it’s kind of obvious. However, intermittent fasting is beneficial for your health and you may still want to take advantage of it. I would recommend fasting only 12 -14 hours a day with maybe a 24 hour fast once every week or two. Another great idea would be to focus your workout efforts on strength training to look and feel more muscular. Make sure you eat plenty of calories from nutrient-dense foods. Eat a higher proportion of carbs (at least 65%) and make sure you are consuming enough protein (30 grams three times a day).

Intermittent Fasting According to the Endomorph Body Type

If your body type is closest the the endomorph type, you can tap into longer fasting periods. OMAD (One Meal a Day) may work very well for you. Or, if you prefer, you could fast for 36 hours twice a week (this is called Alternate-Day Fasting). These longer fasts will help stabilize your insulin level and limit fat storage.

Intermittent Fasting According to the Mesomorph Body Type

The mesomorph body type could go for a middle-of-the-road approach. Listen to your body and experiment to see what makes you feel your best. I would start with the 16:9 method and go from there.

In Summary

While body types are not all cut and dry, they do give you a general idea of how your metabolism is functioning and may help you decide the best approach to get started with intermittent fasting. I recommend you read How to Decide Which Intermittent Fasting Method Is Best for You for further guidance.