Important:
- Health Tab and Body Profile are currently available only to BodyScan 2 and BodyFit users with the 8.8 version of the Withings App.
Your Body Profile, nested under the Health Tab, is a descriptive identity sourced from a pool of 16 profiles that are calculated by combining two measurements from your scale: Skeletal Muscle Index (SMI) and Fat Mass Index (FMI). Your Body profile provides you with a more engaging and relatable identity for your overall health and fitness.
Body Composition Zone
This 16-zone matrix contains a range of 'body profiles' that correlate to your SMI and FMI. These profiles are calibrated to age and sex- because healthy ranges for muscle and fat naturally differ between people of different sexes and ages.
Understanding Your SMI and FMI levels
Skeletal Muscle (SMI)
Your skeletal muscle mass relative to your height, reflecting the muscles you actively build through exercise.
Your body contains different types of muscle, including the muscles inside of your organs. SMI focuses specifically on skeletal muscle: the muscles attached to your bones that you use to move, lift, and balance. These are the muscles you can actively shape through exercise. They tend to decline gradually with age, but regular strength training is the most effective lever to maintain or rebuild them. SMI measures this skeletal muscle mass relative to your height (kg/m²).
| Very High | Exceptional muscle mass relative to your height, typical of highly trained athletes. This level supports a strong resting metabolism and physical performance. |
| High | Your muscle mass is above average for your height,. This supports metabolism, mobility, and long-term resilience. |
| Normal | Your muscle mass is within a healthy range for your height. Regular strength training can help you build further. |
| Low | Your muscle mass is below the expected range for your height. Resistance training paired with adequate protein intake is the most effective way to build it back. |
Fat (FMI)
Your fat mass relative to your height - isolating the fat component for a clearer picture than BMI alone.
Fat Mass Index (FMI) measures your fat mass relative to your height (kg/m²). Unlike BMI, it isolates the fat component, giving you a clearer picture of whether your fat level is healthy independent of muscle.
| Very High | Your fat mass is significantly elevated,m which adds load on the heart and metabolism over time. Small, consistent changes in activity and nutrition make a measurable difference. |
| High | Your fat mass is above the recommended range. Combining regular activity with balanced nutrition supports a gradual return to a healthier range. |
| Normal | Your fat mass is within the expected range for your height. A healthy amount of body fat is essential for energy storage, hormone balance, and organ protection. |
| Low | Your fat mass is below average for your height. Paired with adequate muscle, this reflects a lean, healthy profile. |