What happens when fat infiltrates muscle?

Koo 2022

I previously posted a DrDavisInfiniteHealth blog post on the issue of ectopic fat, i.e., fat accumulating in peculiar and unexpected body locations such as the heart, knees, hips, pancreas, and kidneys. Accumulation of fat on the surface of the heart and enveloping the coronary arteries, so-called “epicardial fat,” for instance, significantly increases risk for heart attack, congestive heart failure, and heart rhythm problems. (Addressing cholesterol, by the way, does NOTHING to address risk for heart disease coming from this phenomenon, another example of how useless, or at least incomplete, cholesterol reduction is to reduce heart disease risk.) Excess kidney fat impairs kidney function. Fat accumulating in joints like knees and hips causes degradation of cartilage and thereby accelerates arthritis.

We therefore want to stop thinking about weight loss per se but about achieving beneficial effects on body composition that avoid the problems caused by weight loss while amplifying health benefits. One of the pivotal issues here is preserving or increasing lean muscle mass. I don’t mean bodybuilder or Arnold Schwarzenegger-levels of muscle, but restoration of the musculature you enjoyed when you were 25 or 30 years old. Recall that, as we age, we lose about 30-35% of muscle. Preserving or increasing muscle can prevent the increased death rate that we now know accompanies weight lost by cutting calories. Such strategies also address the earlier death predicted by the presence of myosteatosis—these are not just cosmetic issues, but issues that impact lifespan, vigor, and maintaining independence.

In other words, muscle takes center stage in importance in crafting your healthy and attractive body composition. You want bulges in the right places like shoulders, neck, and thighs, not the wrong places like pancreas, heart, or hips. The greater your degree of overweight, the larger your waist circumference, the more fat encircles abdominal organs, the more likely muscle becomes infiltrated with fat, a phenomenon called myosteatosis. (And being slender does not necessarily free you from these situations, as there is a common conditioned called “skinny fat” that I shall discuss in greater detail in future.) Fat infiltration of muscle reduces strength, amplifies risk for many health problems, even shortens lifespan by several years.

These are phenomena that you have tremendous control over. To start, abdominal visceral and ectopic fat respond to the strategies we follow in my programs, strategies that include:

• Elimination of wheat, grains, and sugar
   
• Restoration of important nutrients lacking in modern lives that, when combined, reduce insulin resistance and inflammation: omega-3 fatty acids, magnesium, iodine, vitamin D
   
• Addressing dysbiosis, SIBO, and endotoxemia, phenomena that also add to insulin resistance and inflammation
   
• Restoration of Lactobacillus reuteri that, via oxytocin, provokes increased muscle mass and reduction of abdominal visceral and ectopic fat
   
• Restoration of Lactobacillus gasseri that reduces abdominal visceral fat (likely via reduction in endotoxemia)
   
• Increased intake of collagen that adds to increased muscle and reduced abdominal visceral fat
   
• Strategies that increase myokine release, i.e., hormonal mediators of muscle growth

Exercise is only modestly helpful in reducing abdominal visceral and most forms of ectopic fat. But there is an important exception: myosteatosis or muscle fat. This fat is not very responsive to the above strategies, but is exquisitely sensitive to exercise. Here is a graph of some of the results from the Lifestyle Interventions and Independence for Elders pilot (LIFE-P) study conducted at the University of Pittsburgh:

Goodpaster 2008

The level of exercise was mild to moderate, consisting mostly of walking and home exercises such as pushups and squats. Over one year, intermuscular adipose tissue (IMAT or myosteatosis) increased in the non-exercising control group, with no additional increase (but also no decrease) in IMAT with these modest efforts. Would a more intensive or prolonged exercise effort have reversed fat infiltration in muscle? Do our added strategies such as L. reuteri and oxytocin, L. gasseri, collagen peptides, and strategies that increase myokine release stack the odds further in favor of reversing any myosteatosis?

In the meantime, know that, by engaging in my programs and strategies, you are achieving results that improve body composition and minimize or eliminate the excess risk from both abdominal visceral and ectopic fat, including myosteatosis. I also invite you to obtain the added benefits discussed in my newest book due out in December, 2025: Super Body: A 3-Week Program to Harness the New Science of Body Composition and Restore Your Youthful Contours. After receiving years of largely ineffective advice that has contributed to the most overweight population on the planet, now experiencing deteriorating health and shortening lifespan, you can now have access to the newest information, a new paradigm in seizing control over weight and body composition.

Pre-order Super Body at the following locations:

The original IHB post is currently found on the: ⎆Infinite Health Blog, but accessing it there can require an unnecessary separate blog membership. The copy of it above is complete, and has been re-curated and enhanced for the Inner Circle membership.