The Quran says:

2:183 O ye who believe! Fasting is prescribed to you as it was prescribed to those before you, that ye may (learn) self-restraint

A text from scripture:

To worship God. Luke 2 tells the story of an 84-year-old prophetess named Anna. Verse 37 says, “She never left the temple but worshiped night and day, fasting and praying.” Anna was devoted to God, and fasting was one expression of her love for Him.

Fasting is always used as worship towards God and to draw closer. It can be useful for repentance and to make important decisions. It doesn’t necessarily have to be abstaining from food. It can be things that you do on a day-to-day basis. Since food is a necessity then that is the main thing that people go for. Social media is another thing that people gravitate towards that you can “fast” from doing. You can set meat aside for a set period of time and just do fruits and vegetables. The object is not only to become closer to God, but to gain clarity, renewed vigor, and self-control.