We sync a few data points when you log your weight with and App Gallery scale partner..
WEIGHT
Your weight entry for the current date will be updated in your MyFitnessPal account whenever new weight data is synced from your connected scale to the scale's website.
BODY FAT %
When you first link your MyFitnessPal account with a scale partner that measures your body fat percentage, a new body fat percentage measurement will be added to your Check-In/Progress area. When the partner's scale records your body fat percentage, this data point will sync to the scale's website, and then to MyFitnessPal.
NEWS FEED POSTS
If you have elected to have Weight Loss posted to your MyFitnessPal News Feed, an item will appear on your News Feed including the amount of weight lost since your last weigh-in, your total weight lost so far, and will attribute the weigh-in activity to the App Gallery partner's device.