Understanding How Your Body Composition Affects Bone Health and Overall Well-being

We have some exciting and important information to share with you! This newsletter is all about understanding how your body composition impacts your health, especially for women over 40 who are concerned about bone density and staying active. Let's dive into the findings from a recent study titled "Relationship of Fat Mass Index and Fat Free Mass Index With Body Mass Index and Association With Function, Cognition and Sarcopenia in Pre-Frail Older Adults."

Key Insights:

1. What is Body Composition?

   • Body Mass Index (BMI) is a common measure, but it doesn’t tell the whole story. BMI is calculated by dividing your weight (in kilograms) by your height (in meters) squared (kg/m²). It doesn't distinguish between fat and muscle.

   • Fat Mass Index (FMI) and Fat-Free Mass Index (FFMI) are more detailed measures. FMI looks at the amount of fat in your body relative to your height, while FFMI focuses on your muscle and bone mass.

2. Why BMI Falls Short:

   • Lack of Detail: BMI can be misleading because it doesn't differentiate between fat and muscle bone. For example, two women could both have a BMI of 25. One might have a high muscle mass and increased bone density (good health), while the other might have high fat mass (not so good health).

   • Example: Imagine two women, both with a BMI of 25. One is a regular at the gym with strong muscles, while the other might be less active with higher fat. Their BMI is the same, but their health is very different.

3. Why FFMI is Better:

   • Clearer Picture: FFMI gives you a better idea of your muscle mass relative to your height. This is important for understanding your true health status.

   • Muscle Matters: Higher muscle mass (FFMI) is linked to better physical function and brain health. For women over 50, keeping or building muscle can mean better mobility and mental sharpness.

4. How to Measure FFMI:

   • Step 1: Determine your fat-free mass, which includes muscles, bones, water, and other non-fat tissues. This usually requires tools like bioelectrical impedance analysis (BIA) aka body scan (more readily available, no referral required, more cost effective ~$35 on the other hand less accurate compared to DEXA) or dual-energy X-ray absorptiometry (DEXA).

   • Step 2: Calculate FFMI with this formula: FFMI = (Fat-Free Mass in kg) / (Height in meters)².

   • Example Calculation: If you weigh 60 kg and your fat-free mass is 45 kg, and your height is 1.6 meters, your FFMI would be:

     • FFMI = 45 / (1.6)² = 17.6

5. Risks of High Fat Mass:

   • A higher amount of fat compared to muscle (high FM/FFM ratio) can lead to poorer physical function and higher rates of muscle loss (sarcopenia) and sarcopenic obesity. This can affect your mobility and bone health.

6. Protecting Bone Health:

   • Sarcopenia, the loss of muscle mass, can lead to physical frailty and reduced bone density. Focusing on maintaining muscle mass is key to preventing osteoporosis and staying active.

7. Practical Tips:

   • Exercise: Try resistance training and weight-bearing exercises to build muscle.

   • Nutrition: Make sure you’re getting enough protein to support muscle health.

   • Regular Check-ups:  Keep an eye on your body composition and bone density so you can see what works and what doesn't in your bone-building plan.

Conclusion:

Maintaining a healthy balance of muscle and fat is crucial for staying active and healthy as we age. By focusing on building and preserving muscle mass, you can improve your quality of life and reduce the risk of frailty and osteoporosis.

For more detailed information, you can refer to the original study by Reshma Aziz Merchant and colleagues, published in the journal Frontiers in Endocrinology.

Stay active, stay healthy, and take charge of your bone building plan today!

Reference: Merchant RA, Seetharaman S, Au L, Wong MWK, Wong BLL, Tan LF, Chen MZ, Ng SE, Soong JTY, Hui RJY, Kwek SC, Morley JE. (2021). Relationship of Fat Mass Index and Fat Free Mass Index With Body Mass Index and Association With Function, Cognition and Sarcopenia in Pre-Frail Older Adults. Front. Endocrinol. 12:765415. doi: 10.3389/fendo.2021.765415.