Tuesday, July 13, 2021

Relation of fat mass and muscle mass to risk of all cause mortality

The Study

Subjects from 7 different prospective cohort studies had their body composition measured and were followed for an average of 14 years. Over 16,000 subjects were included in this investigation.

Here is what the researchers found:

-When compared to subjects with the lowest body fat, those with the highest body fat had a 56% increased risk of dying from any cause.

-When compared to subjects with the least muscle mass, those with the highest muscle mass had a 30% lower risk of dying from any cause.

-The BMI of the subjects correlated extremely well with their body fat (r = .813).

-The BMI of the subjects also correlated very well with their muscle mass (r = .710).

American Journal of Clinical Nutrition 2021; 113:639-46.  

Take Home Message

This study shows us the importance of not only maintaining a healthy weight, but of preserving our lean body mass. We start to lose muscle after the age of 25. If we don’t actively work on maintaining our muscle, this loss can have a seriously negative impact on our health and ability to function as we age. Hit the weights at least twice per week to prevent the loss and even add to your lean body mass. 

One other interesting note from this study: body mass index was highly correlated with both body fat and lean body mass in this large population. There are many who think it is not an important measure. This study shows that it truly is.

Can supplementing with protein improve muscle mass and strength?

The Study

Age related loss of muscle results in a decrease in quality of life and ability to function. It has been theorized that protein supplementation may slow down this loss of muscle that is a normal part of aging. In this interesting 1 year randomized trial, 208 healthy adults over the age of 65 were randomized into 1 of 5 groups:

1) Carbohydrate supplementation- 30 grams per day.

2) Collagen protein supplementation- 20 grams per day.

3) Whey protein supplementation- 20 grams per day.

4) Light resistance training with bands- 3 times per week.

5) Heavy resistance training with weights- 3 times per week.

By the end of the year, the following results were found:

- The protein supplement groups had no improvements in measures of strength or muscle size.

- The resistance groups had improvements in muscle strength and size.

- The groups supplemented with protein and carbohydrate had an increase in percentage of body fat. American Journal of Clinical Nutrition 2021; 113:790-800.

Take Home Message

Don’t expect a protein supplement to improve your strength or muscle size on its own.  Weight training is how you make that happen. Hit the weights at least twice per week with a full body workout. Three times is even better!


Product Review: Tanita Ironman Scale

When deciding on which products to review for this newsletter, I always ask myself two questions: 1) Will this product make it easier for my clients to succeed in attaining their health and fitness goals?  2) Am I asked about this type of product on a regular basis? An accurate, reliable scale answers both of these questions with a resounding “Yes”. Therefore, it is time to review the Tanita Ironman BC554.

When your goal is to lose weight, you need an honest, consistent and objective measure of your progress.  If what you are doing is working, keep going with it!  If not, you need to make some changes. If you are not weighing yourself regularly, you will not be able to tell what is working and what is not. To do this, you need an accurate and reliable scale. I have been a huge fan of Tanita Ironman scales for years. I currently have the Ironman BC554.


1) Accuracy. I consider the Tanita Ironman line research quality. Knowing you have an accurate measurement is, for obvious reasons, pivotal.

2) Durability. My last model lasted me for almost 10 years.

3) Long battery life. I am amazed at how long the batteries last in these scales. You go years without having to replace them.

4) Measures body fat. If you are lifting weights while you are losing weight, a time may come where you will be building muscle and losing body fat at largely the same rate. This can become a bit frustrating as the number on the scale stops going down. At this point, your percent body fat is a better indicator of progress than your weight. Tanita Ironman scales come with a bioelectrical impedance analyzer to measure body fat. When used correctly, these scales provide an accurate measure of body composition which can become a very useful measure of progress toward your goals. Studies have shown that bioelectrical impedance with a Tanita scale has a high and significant correlation with DEXA, which is the gold standard of body fat analysis (Reference 1-2).


1) A bit pricey. The BC554 currently lists on Amazon for $172.99. This is a lot for a scale.

Would I Recommend Tanita Ironman Scales?

Without a doubt. These scales can be a bit on the pricey side, but they last forever, are highly accurate, and allow you to measure your body fat. Overall, they are a great investment in your health. 

To learn more about Tanita scales, visit Tanita.com. If you want to buy one, you can pick it up on Amazon.com.  If you want more information about the proper way to weigh yourself, check out this previous post.

Disclosure: I have no relationship with the Tanita company and make no money if you buy their products.


1) Rubiano F, et al. Validity of consumer model bioimpedance analysis system with established dual x-ray absorptiometry (DEXA). Presented at ACSM 46th annual meeting. Poster.

2) Rubiano F, et al. Comparison of body composition techniques. Presented at The International Symposium Of Invivo Body Composition Studies 1999. Poster.