An image of a typical vegetable-based diet in Jerusalem.

The Daniel Fast, named after the Old Testament prophet, recommends eating fruit, vegetables and whole grains and drinking water, while avoiding meat, fish, bread and sweetened or processed foods,the UK’s Daily Mail reported on Thursday.

Susan Gregory, author of The Daniel Fast, told the newspaper that the plan is drawn from the Book of Daniel, which describes the prophet’s response to a command from King Nebuchadnezzar of Babylon to eat the same food he was eating to gain strength. But Daniel refused the king’s menu, saying it had not been prepared according to Jewish standards.

The Book of Daniel (1:8) says, “But Daniel purposed in his heart that he would not defile himself with the portion of the king’s meat, nor with the wine which he drank.”

Instead, Daniel vowed to eat nothing but foods grown from seeds and drink only water. Later, Daniel fasted again while seeking God’s word on the future of Israel and described this fast as involving no meat, wine or leavened bread, according to Gregory’s account to the Daily Mail.

The Book of Daniel (10:3) says, “I ate no delicacies, no meat or wine entered my mouth, nor did I anoint myself at all, for the full three weeks.”

These biblical descriptions of Daniel’s fasts formed the basis of her diet.

In an interview, Gregory described The Daniel Fast as a “vegan diet with even more restrictions,” which includes avoiding caffeine, chemicals and sugar, which she says can ease headaches, leg cramps and fatigue. The diet can also lead to lower cholesterol levels and balance blood sugar levels, as well as weight loss and “a general feeling of well-being,” Gregory said.