Why Body Composition Matters More Than Weight Loss: A Ketogenic Approach with Dr. Bret Scher

Bret: Here’s a controversial take. Losing weight is not going to make you healthier, not if your only goal is reducing the number on the scale. Instead, focusing on losing fat mass. Maintaining or building lean mass, like muscle and bone and improving metabolic health are the keys to improving your overall health.

And while wildly popular and successful for weight loss medications like Wegovy and ozempic don’t really differentiate between fat and muscle loss. So what does, while evidence indicates that ketogenic diets can have a more prominent impact on body composition and metabolic health, so could that help you?

Let’s get into the details. Welcome to Metabolic Mind, a nonprofit initiative of Baszucki Group, transforming the study and treatment of mental disorders by exploring the connection between metabolism and brain health. Thank you for joining us on this journey. Have you heard the term Ozempic butt? I just heard it for the first time the other day.

It is a little glib, of course, but essentially it refers to people who lose weight with ozempic, but notice they lose significant amounts of muscle in their glutes, so they lose their butt. But this underscores the problem with focusing on weight loss as a primary outcome as opposed to body composition.

But before we get into the details, please remember, our channel is for informational purposes only. We’re not providing individual or group medical or healthcare advice or establishing a provider patient relationship. Many of the interventions we discussed can have potentially dangerous effects if done without proper supervision.

Consult your healthcare provider before changing your lifestyle or medications. In addition, please recognize that people may respond differently to ketosis and there isn’t one recognized universal response. So here are the main ways to help lose fat. Build muscle mass and improve metabolic health. Eat an adequate amount of protein, somewhere around 1.5 grams per kilogram of reference body weight.

Do regular resistance exercises such as weightlifting or even body weight or band exercises, and potentially a third one is eat a ketogenic diet. What isn’t on the list is taking new weight loss drugs like Wegovy, Ozempic, or Manjaro. Now to be fair, those drugs do help with substantial weight loss and the metabolic improvements that come with that weight loss, but they also cause substantial loss of lean muscle mass.

In the landmark Semaglutide study in the New England Journal of Medicine, the supplementary results show that of the subjects who had DEXA body composition scans, they lost 10 kilograms of fat mass. But also lost seven kilograms of lean mass. That’s 40% of their weight loss coming from their muscles, not something that is conducive to future strength and functionality.

So although they significantly improve metabolic health in the short term, it’s a fair question to wonder what will happen in the long run if they don’t build back the muscle mass. Or even worse, what if they stop the medication because of side effects or cost concerns? And they gain back the fat mass without the muscle mass.

But a ketogenic diet shows very different results. Now, some studies have been done in trained athletes and those demonstrate fat mass loss with no significant muscle mass loss. But since these were healthy trained athletes, the overall weight loss was small. And it’s not a true comparison, but we have other studies.

So one looked at four months of a ketogenic diet in individuals with obesity, and it found 20 kilograms of weight loss. 18.5 of which were from fat mass. So not only is the absolute weight loss greater, but there was almost no lean mass loss. And the authors actually concluded that the quote unquote lean mass loss was actually likely water weight and not muscle loss.

Results from Virta Health’s two year study of a ketogenic intervention reported loss of 12 kilograms and only 1.3 kilograms of that was lean mass. Now, not to confuse the matter, but there are also some studies that demonstrate no difference in lean mass loss between a keto and a higher carb diet. When they are isocaloric, meaning they’re forced to all eat the same amount of calories, but when they’re allowed to eat as much or as little as they want, that’s when we start to see the sparing of lean mass with ketosis.

So an interesting caveat, but here’s another caveat. These studies are done. With the more modern keto diet or modified Atkins diet, not the very low protein four to one keto diet that was used in seizures and that we’ve talked about before in our channel. And that’s important because we likely still need adequate protein, even with ketosis to maintain or build muscle mass.

And of course, the more we move and stress our muscles, the better. So many questions still remain like, would a lower protein keto diet without exercise still maintain body composition? Maybe, but probably not as well. And would resistance training plus high protein alleviate the lean muscle loss with ozempic and wegovy?

Now, that study hasn’t been done, but at least anecdotally, many of the doctors who prescribe the medications, and many of the patients I’ve spoken with, they notice that the feelings of fullness and nausea associated with the medications. Drive them more toward comfort foods or easy to digest carbs rather than the protein based foods that could account for some of the lean muscle loss.

So let’s wrap this up and summarize. Now, weight loss may not be the best primary goal. Losing fat mass, preserving or building muscle mass and improving metabolic health are likely better. Long-term goals, eating at least moderate protein and getting regular resistance training are keys in this equation.

And a ketogenic diet may provide better body composition results than other dietary forms of weight loss. And popular GLP one. Weight loss drugs are terrible for maintaining lean mass. Now, that doesn’t mean they should never be used, but be warned and if someone does use them, it may be a good idea. Try along with it, a keto diet with adequate protein and regular resistance training to hopefully offset the loss of lean mass.

So I hope this perspective was helpful. If it was, please and subscribe so you won’t miss any of our future videos. And please leave us a comment. Let us know your experience with body composition changes, what worked and what didn’t work for you. As always, thank you for watching. I’m Dr. Bret Scher and we’ll see you here next time at Metabolic Mind, a nonprofit initiative of Baszucki Group.