Following are a number of back-translations as well as a sample translation for translators of Proverbs 17:22:

• Kupsabiny: “If/when a person is joyful/happy his body is healthy,
  but if he is annoyed/angry, his bones breaks (he loses hope and strength).” (Source: Kupsabiny Back Translation)
• Newari: “A happy heart is like good medicine,
  If [you] are always feeling broken-hearted
  [your] bones will dry up.” (Source: Newari Back Translation)
• Hiligaynon: “If you (sing.) are happy, it can-make- your (sing.) body -healthy/[lit. good], but if you (sing.) are sad, it can-make- you (sing.) -sick.” (Source: Hiligaynon Back Translation)
• Kankanaey: “Happiness causes-(one)-to-be-strong like medicine, but sorrow, it causes- the body to-be-weak.” (Source: Kankanaey Back Translation)
• English: “Being cheerful is like swallowing good medicine;
  being discouraged/gloomy all the time will drain away your energy/cause you to become weak.” (Source: Translation for Translators)