Researchers are further uncovering that visceral fat (midsection among organs) is the only body fat storage inherently problematic: https://newsroom.heart.org/.../more-belly-weight....
To be clear, some insulating fat under the skin doesn’t have a theorized mechanism for raising health risk nor an epidemiological statistical connection to increased health risk. In fact, what we do know is that UNDERweight people have higher cardiovascular health risk (https://pubmed.ncbi.nlm.nih.gov/29981771/), more issues with infertility (https://pubmed.ncbi.nlm.nih.gov/32289345/), and cognitive decline (https://pubmed.ncbi.nlm.nih.gov/26294005/).
Why would this be?
All of the hormones which keep us alive and let us thrive are derived from or regulated by fats. Too high is an obvious problem. But we tend not to think about how too low must likewise be a coequal or greater problem.
And, to be fair, underweight BMI is not prevalent in the industrialized countries.
But what’s so special about visceral midsection fat versus subcutaneous fat?
Again, we tend not to think about how internal organs require a certain amount of space, a balance of pressures, blood flow, and alignment. As the body aggregates fat storage around organs, these functions are impeded. There is literally pressure squeezing on the lungs, the kidneys, the liver, and so on.
Where I first see this is in posture. The person will “make space” in order to breathe, by increasingly extending the low back in order to open up the abdomen and try to make room for organ function. This leads to chesty breathing which induces persistent anxiety. Combined, the risk of elevated blood pressure is nearly assured. Fatigue, likewise, must eventually ensue, as the person is perpetually doing a minor (or major) back bend and stretching the abdominal muscles and obliques. Shoulders shrug up to allocate more space. Distance between hips and rib cage continue to increase in hopes of making room for internal organ function.
This adaptation can only scale so far. Ultimately, people will find they cannot ever take deep breaths into the lower 2/3 of the lungs. Stress, allergies, and respiratory difficulty amplify. Liver and kidney function is consistently impeded. Digestive function, likewise, has a fair degree of pressure. Walking gait also devolves because the lordotic lumbar curve is magnified. Chronic discomfort and hip/low-back pain is a constant. It has nothing to do with added “weight” necessarily, and everything to do with compression and non-neutral postures.
I have found that people who make a targeted effort at dropping overall body fat will eventually remove visceral fat. To be sure, all of my clients who clock low DEXA scan body fat obtain low or even N/A visceral readings.
Weight may matter a little bit. But having piles of useless energy storage crushing internal organs is ruining health prospects, mental health, and general enjoyment of what could be an energized, joyful, and easy-breathing experience.