Why Is My Body Skinny Fat?

I first asked, “Why is my body skinny fat?” more than four decades ago. When I was eight years old, I asked the doctor about the “weird fat” all over my body where there should be muscle. They brushed it off as “normal” and told me the muscle would grow in time. I was within safe BMI, and thus, “normal”.

Puberty hit late, no muscle. I remained scrawny and weak, unlike most of my peers. The excess regular white/yellow fat became harder to keep at bay. I secretly watched my diet as I refused to be overweight or obese, both of which are common in my family. Another visit to the doctor revealed the same response, “You are within safe BMI and normal”. They offered no muscle tissue measurement and no definition of what amount of muscle tissue is “normal”. They grossly assumed.

Nothing has changed more than four decades later. At least science/medicine has come to recognize the term skinny fat, and even offer an initial definition. Although the definition directly contradicts (1, 2) The Standard BMI, and does nothing to explain why my body is skinny fat. Let alone what can be done about it. Instead, I am told I need to lose more regular fat weight, regardless of the fact that I am well within safe BMI. Even when I have lost weight down near a minimum BMI of 18.5, the skinny fat did not go away — the missing genetic muscle did not magically appear.

Why Is My Body Skinny Fat?

Determined to understand why my body is skinny fat and how to fix it, I have spent decades scientifically researching it, including honing my diet, consistently body recompositioning via resistance exercise/lifting weights, and doing diverse cardio, no less. Yet, no matter how hard I work, the best I can do is reduce the copious skinny fat all over my body. If I stop weightlifting, it leads to the added muscle mass dissipating, which makes the skinny fat front and center once again. Just as straying from a strict diet easily manifests additional unwanted regular white/yellow body fat, worsening the skinny fat appearance.

Further visits to the doctor have concluded with the same BMI spiel. I am within safe BMI and normal. No recognition of the copious weird fat all over my body. Well, other than to inappropriately tell me I am still eating too much, still have too much regular body fat, and need to lose more weight. Even though I am, as the doctor clearly states, “within safe BMI and normal”. Any request for an MRI scan to actually measure my natural, genetic muscle tissue falls on deaf ears. Because no such measurement exists. Even if an MRI is granted (insurance), there is no average muscle tissue measurement to compare it to. There is, and has never been, any way to officially diagnose skinny fat. Our MRI Study (3) is working on a solution.

The Science

As the scientific research (4) has grown, the evidence paints a clear picture. I never had the genetic muscle tissue to begin with, and where it should be, is skinny fat. I am not alone. Our science indicates that roughly 2/3rds of the population is experiencing some degree of skinny fat (lack of genetic muscle). To date, this is what the science offers in terms of data, evidence, and facts:

• Muscle tissue is genetic (5, 6). How much natural muscle tissue each person is born with (or not born with) is determined by genetics. Some people have more muscle, some less. There is no science to support the gross assumption that every human being is born with the same general amount of muscle relative to height and gender. None.
• Safely losing regular white/yellow fat down to a safe minimum BMI of 18.5 does not (7, 8) get rid of or cure skinny fat, for those who are experiencing it. It can help reduce the appearance of skinny fat. Starving/losing fat weight below a BMI of 18.5 does not magically cure a lack of genetic muscle (skinny fat).
• Adding muscle mass does not (8, 5) get rid of or cure skinny fat, for those who are experiencing it. It can help reduce the appearance of skinny fat, depending on how much you are experiencing. But fat cannot turn into muscle, and muscle cannot turn into fat. As soon as you stop doing the exercise that built the muscle mass, you will gradually lose it and eventually return to your original genetic body composition, including any skinny fat.
• There is and has never been a way (3, 2, 1) to accurately measure natural, genetic muscle tissue.
• There is and has never been an average genetic muscle tissue measurement to compare #4 to (above average, average, below average).
• There is no scientific data that accurately determines what skinny fat tissue (1) — thin fat, cellulite — is, where genetic muscle tissue should be, but is not.
• Skinny fat science is very young, and a skinny fat diagnosis does not exist (1, 2, 3) at this time.

My body is skinny fat due to my genetics. The only way we can definitely prove this is with the MRI Study (3).

Scientific Health Quizzes – Understanding Skinny Fat

Nearly 25 years of scientific research has allowed for the development of the Scientific Health Quizzes. The Scientific Body Type Quiz accurately determines skinny fat (our MRI Study is working on officially verifying this). The Scientific Metabolism Quiz, Scientific Diet Quiz, Scientific Exercise Quiz, and Scientific Lifestyle Quiz help you better understand your health and how it all affects your body composition.

Easily track your data and progress over time. Accounts are free, private, secure, and anonymous (pending what information you choose to give). Free options are available.

References

1. Skinny Fat Science: What Is Skinny Fat?, July 26 204. https://skinnyfat.fellowone.com/skinny-fat-science/what-is-skinny-fat/
2. Skinny Fat Science: Skinny Fat is a Lack of Genetic Muscle – Beyond Normal-Weight Obesity, August 13, 2025. https://skinnyfat.fellowone.com/skinny-fat-science/skinny-fat-is-a-lack-of-genetic-muscle-beyond-normal-weight-obesity/
3. Skinny Fat Science: Scientific Skinny Fat MRI Study – Proving What Skinny Fat Is, March 26, 2025. https://skinnyfat.fellowone.com/skinny-fat-science/scientific-skinny-fat-mri-study-proving-what-skinny-fat-is/
4. Fellow One Research: Body Type Science Research Data. https://www.fellowone.com/category/fellow-one-research/the-four-body-types/body-type-science/research-data/
5. Skinny Fat Science: Is Muscle/Mass Genetic and How Does It Affect Skinny Fat?, November 20, 2024. https://skinnyfat.fellowone.com/skinny-fat-science/is-muscle-mass-genetic-and-how-does-it-affect-skinny-fat/
6. Skinny Fat Science: Is Skinny Fat Genetic?, November 27, 2024. https://skinnyfat.fellowone.com/skinny-fat-science/is-skinny-fat-genetic/
7. Skinny Fat Research: Are Regular Fat and Skinny Fat the Same Thing?, August 28, 2024. https://skinnyfat.fellowone.com/skinny-fat-science/are-regular-fat-and-skinny-fat-the-same-thing/
8. Skinny Fat Research: How To Fix Skinny Fat, July 27, 2024. https://skinnyfat.fellowone.com/skinny-fat-science/how-to-fix-skinny-fat/