Beware low muscle mass!

ChiSandy

Low muscle mass a mortality risk in early-stage breast cancer

Just read this new Medscape article, which found BMI alone, even simple body fat %, is less predictive of risk for death than is low muscle mass in patients with Stage II or III breast cancer. There are two forms of muscle deficit: sarcopenia, aka excessively-low absolute muscle mass; and its precursor, reduced muscle density--which can be revealed via CT scan. CT scans can distinguish between adipose tissue (body fat) and muscle, and reveal how dense the latter is--thereby presenting a more accurate measure of body composition than BMI alone. A muscular athlete with high and dense bone mass can--measuring only height & absolute weight--score "overweight" or even "obese" in BMI, whereas a sedentary slender person with a "healthy" BMI can have too little muscle and mostly fat & bone.

Oncologists were warned by this article to think twice about advising high-BMI Stage II or III patients to "lose weight," because the weight lost via diet includes lean muscle mass as well as body fat. Protein supplementation was addressed: in patients with sarcopenia or low muscle density, increased dietary protein intake was advised, but from actual food sources--not shakes, liquids or powders. Evidence for the efficacy of the latter is thus far limited only to those patients with metastatic cancer and cachexia.

Early-stage breast cancer patients, the article says, should be placed on a resistance-training program (e.g., weights or elastic bands) not just to improve strength but also to build muscle mass--and if excessively adipose (high fat %), achieve weight loss that burns more fat and minimizes muscle loss. As to BMI alone, there was no clinically significant survival difference between normal, overweight, and even mildly obese patients. The highest-risk group is both excessively adipose and sarcopenic--but that is relatively rare (only 7% of patients surveyed).

Caveats:

1. The study cohort consisted only of Stage II and III patients. The effect of low muscle mass on Stage 0 or I patients was not mentioned, and these patients may not even have been studied.
2. The mortality risk is for death from breast cancer, not all-cause mortality. Therefore, high-adipose % regardless of muscle mass and stage of breast cancer is probably still a significant risk factor for cardiovascular and coronary heart disease; and intervening causes of death such as pulmonary, kidney or liver disease, poisoning, infection or trauma from accident or violence are totally unpredictable.
3. So if you are Stage I with too much body fat but normal muscle mass, you're not home free. Breast cancer probably won't kill you--when you die (as we all will) it will likely be from a heart attack, stroke, heart failure, COPD, sepsis, or massive injury, just like the population at large.

ksusan

Nice summary. Thanks!

couragement

Thank you so much for posting this article. Just had a long visit with my internal med doc yesterday and this was the topic. I have been trying to lose weight to help myself along (only need to lose about 15 pounds) but it is not coming off and I take in many fewer calories than I used to. But other longer lasting side effects from treatment are keeping me from strong exercise, so my doctor gave me some meds to help boost my energy from my insomnia in order to get me into the gym. He agreed that this one of the most important things I can do for myself. The importance of muscle over fat! So I appreciate the synchronicity of this article and am off to call a trainer to help get me going .

Sending you my very best! May we all be well!

BrooksideVT

Really interesting.  Confirms my onc's focus on exercise, especially walking.

ruthbru

Exercise is, by far, the biggest no-medical thing we can do to reduce the chance of recurrence (plus just about every other disease/condition as well). Aerobics and toning are of equal importance. It should be a top priority is all of our lives!

Racy

Thank you for posting this information about the importance of muscle mass. I've recently started doing weight exercises so this will give me added incentive to continue.

Couragement, I understand it is hard to lose weight. I've been exercising for about 3 months and only lost 2 pounds (on a good day).

I've seen a lot of people seem to achieve results more easily through reducing carbs and replacing them with protein. This is also said to be good for muscle development.

Egads007

Excellent article! I've been 'pushing iron' for just over 3 years now and it's made an enormous difference...mind, body and soul. For those interested, there are many more 'calculators' than BMI available to gauge progress. BMI can be deceptive and is definitely limited in the bigger picture. Eg: a 6' man weighing 285 has a BMI of 38.5, which is considered morbidly obese. If that same man has a 15% body fat ratio that would indicate his lean body mass (muscle, bones, organs) is 242.3 of his 285 lbs, in other words the dude is totally ripped. Yet his BMI shows very much the opposite, hence the limitations of BMI charts. One of the best ways to get a clearer picture of healthy body size is to use waistline to height ratio measurement charts, that and several others. PM me if you’re interested.

If you put a pound of fat next to a pound of muscle, the muscle is 22% smaller. I’m 15 lbs heavier than my pre chemo weight yet I float in my clothing from that time. I weigh more but am much smaller. Muscle building also builds stronger bones, something so important as we all know. There is just too much win-win to pass up on when it comes to weight bearing exercise.

As a PS, the article mentions avoiding protein drinks. I see people in my gym swigging it like it’s going out of style. If you want protein, eat a steak, eggs, or whatever protein bearing food you prefer. The shakes may look healthy but many are full of simple carbs(white sugar), not to mention the processing chemicals not listed on the packaging which do leech into the product. Hydrate and eat a protein laden meal with a reasonable complex carb level after the workout..it’s essential, and besides, who doesn’t like to eat?

ruthbru

Egads007

LOL Ruth, exactly! My trainer had both the fat and muscle onher desk. I told her I wanted them for paperweights when I hit my first goal.

Kittykat9876

I know that weight training and aerobic exercise is good for us as well as a healthy diet but it isn't a guarantee that cancer won't come back, I went to the gym five days a week after my first diagnosis and ate all the right food but I didn't even make it 5yrs before it metastasized in my bones and lungs my right femur was so bad I had to have a titanium nail inserted, I have muscles and stage IV cancer. 😢

ruthbru

I am so sorry, Kitty. I hope your otherwise good health will help you manage your treatments better.