Is Skinny Fat Genetic?

The common spiel everywhere but particularly online, especially on Google and social media, is that skinny fat is caused by poor diet and exercise, not genetics. What does the latest science say? Is skinny fat genetic?

There is no debate that a poor diet and deficient protein can lead to muscle tissue loss. Just as insufficient exercise and being too sedentary can also result in lost muscle tissue. The widespread claim is that lost muscle tissue causes skinny fat.

How would that work?

Muscle is unique tissue (1, 2, 3). When muscle tissue is lost, it cannot and does not (4, 5, 6, 7) turn into some other unique tissue, like regular white/yellow body fat/adipose tissue (8, 9, 10, 11). For instance, here is genetically blessed Christian Bale (BT1)(12) when he lost a significant amount of weight including obvious muscle tissue. According to common spiel everywhere, he should be experiencing skinny fat.

But he is not. He is showing no signs of skinny fat. Even when emaciated, he has clear muscle definition, as per the Standard Body Type One (BT1)(13).

If it is true that lost muscle tissue causes skinny fat, then that truth applies universally and unequivocally to all human beings. So, why did Christian Bale clearly lose muscle tissue yet he is not experiencing skinny fat? Because as a genetically blessed Standard BT1, he has all 600+ muscles developed from birth. Genetics.

Is Skinny Fat Genetic?

It is a fact (14, 15, 16, 17, 18, 19) that the total amount of genetic default muscle tissue — the number of Type 1 and Type 2 muscle fibers (20, 21, 22, 23, 24) —  each human being has is set at or around birth. Just as it is a fact that some people have more genetic default muscle/mass from birth, while others have less genetic default muscle/mass from birth. The ratio of muscle fibers each specific person has from birth directly affects how easy or hard it is for them to add (25, 26, 27, 28) muscle mass via proper exercise and maintain it.

Of course, it is very possible to epigenetically add muscle mass (above and beyond default genetic muscle/mass) through exercise, particularly resistance exercise like weight lifting. But, adding muscle mass is not permanent (29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39).

This professional trainer and amateur athlete is within safe BMI (18.5 to 24.99) at 22.7:

They have no excess body fat (regular white/yellow fat/adipose tissue), no visceral fat, no belly, and do not have a low amount of muscle/mass tissue — all of which, according to Google, is how skinny fat is defined:

Yet, they have obvious “weird fat” tissue on their love handles and lower back where genetically they should have default genetic muscle/mass:

Is Skinny Fat Real, Unique Genetic Tissue?

By Standard BT1 definition, they should genetically have default genetic muscle/mass tissue on their love handles and lower back, just like research participant 1000 (40) — but they do not. We know they are within safe BMI at 22.7 and by Standard BMI definition they do not have any excess regular white/yellow body fat — so the “weird fat” on their love handles and lower back is not regular body fat. In fact, they could lose even more regular fat weight and get down to a minimum safe BMI of 18.5 and the genetic default muscle/mass would not magically appear on their love handles and lower back.

Their diet, exercise, and lifestyle routines are healthy (as verified by their doctor and the Scientific Health Quizzes). But, even if their routines were not healthy, we know it is an undisputed fact (4, 5, 6, 7) that lost muscle tissue cannot and does not magically turn into any kind of fat tissue (regular fat, brown fat, beige fat, skinny fat). No process exists in the human body for that to happen.

The “weird fat” on their love handles and lower back (why only on their love handles and lower back?) is unique genetic skinny fat tissue (41). In this case, thin fat tissue. They have had it since birth. Skinny fat is unique genetic tissue that exists where genetic default muscle/mass should be, but is not. Skinny fat is not caused by diet or exercise, although metabolism (42), diet (43), exercise (44), and lifestyle (45) directly influence skinny fat.

How To Determine If You Have Genetic Skinny Fat Tissue

The Scientific Body Type Quiz (Official) was developed to accurately determine and identify if you have genetic skinny fat tissue.

Along with the other Scientific Health Quizzes — Scientific Metabolism Quiz, Scientific Diet Quiz, Scientific Exercise Quiz, and Scientific Lifestyle Quiz — you can accurately calculate your unique metrics to understand your unique genetic body composition and health.

Scientific Health Quizzes

References

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