If you feel the Weight Loss app is slow, one way to possibly make it faster is by following the procedure below, in the same order:
(*This procedure can take little more than 1 or 2 minutes to complete.)
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1) Close all apps
https://support.apple.com/en-us/HT201330
2) Restart your device
https://support.apple.com/en-us/HT201559
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