The ruling on fasting with the intention of worship while seeking health benefits

Question:
The questioner asks: If a person fasts a voluntary fast, but the faster’s intention is to gain health benefits and lighten the burden on the body, does this fast become delayed in that regard? Is it shirk (associating partners with Allah) for a person to contract with wisdom, or not?

Answer:
If the original intention is worship and seeking reward, and it happens that he obtains health benefits, then these are attached to the worship, and there is no harm in that; they are attached to the worship. However, if the original intention is the opposite, seeking health benefits, then there is no reward for it, and this is not worship. Yes, the criterion is the intention, the original intention of fasting. If the original intention is worship, then it is worship, and the health benefits are attached and beneficial. There is no doubt that fasting has health benefits, which is from the grace of Allah (Glorified and Exalted is He). Therefore, the Prophet (peace and blessings be upon him) said to the young men: So he fasts in worship of Allah, and this fasting benefits him sexually by breaking the intensity of desire, so there is no harm in that if the original intention is seeking reward and obtaining the benefits.