The increase in longevity is also clearly associated with a decrease in disease states that would cut your life short, and calorie restriction is associated with a number of health improvements, including reduced visceral fat, reduced inflammation, lower blood pressure, and improved insulin sensitivity,5,6 just to name a few. Earlier research has demonstrated that calorie restriction helps extend the lifespan of animals by improving insulin sensitivity and inhibiting the mTOR pathway.
If the better part of wisdom for you, in your health condition, is not to go without food, consider fasting from television, computer, social media, or some other regular enjoyment that would bend your heart toward greater enjoyment of Jesus. Paul even talks about married couples fasting from sex “for a limited time, that you may devote yourselves to prayer” (1 Corinthians 7:5).
Yes, it's a good idea for believers to fast from time to time. Fasting is not required in Scripture, but it's highly recommended. The primary Biblical reason to fast is to develop a closer walk with God. By taking our eyes off the things of this world, we can focus better on Christ. "When you fast, do not look somber as the hypocrites do, for they disfigure their faces to show men they are fasting. I tell you the truth, they have received their reward in full. But when you fast, put oil on your head and wash your face, so that it will not be obvious to men that you are fasting, but only to your Father, who is unseen; and your Father, who sees what is done in secret, will reward you" (Matthew 6:16-18).
But followers beware, says nutrition researcher Michelle Harvie. Dieters going keto tend to lose weight, but the diets are low in fiber and high in saturated fat, which is a risk for cardiovascular disease. “And there is increasing evidence that its effect on the gut microbiome is pretty adverse,” says Harvie. “The gut microbiome is a poorly understood but potentially important part of our metabolic health. And if you mess that up, you’re in trouble.”
The findings were encouraging for both dieting groups, because they showed that conventional and fasting diets both do lead to weight reduction. However, the results could be considered a disappointment for those hoping that the fasting diet would be a superior option. Turns out the simplest advice is still generally correct: Eat fewer calories, and you’ll lose weight.
Fasting can take up a significant portion of the calendar year. The purpose of fasting is not to suffer, but according to Sacred Tradition to guard against gluttony and impure thoughts, deeds and words.[50] Fasting must always be accompanied by increased prayer and almsgiving (donating to a local charity, or directly to the poor, depending on circumstances). To engage in fasting without them is considered useless or even spiritually harmful.[47] To repent of one's sins and to reach out in love to others is part and parcel of true fasting.
Intermittent fasting, unlike many other diets, is famously flexible in that you choose the days and hours during which you think it’s best to fast. The two most common methods are the 16:8 strategy—where you eat whatever you want (within reason) for eight hours a day and then fast for the other 16—and the 5:2 method, where you eat normally five days a week and then keep your food intake to roughly 500-600 calories for the other two days. It’s kind of a simplified-calories math problem that’s supposed to prevent the yo-yo effect of weight loss and weight gain.

That’s the principle behind the diet method known as intermittent fasting. Unlike many popular diets, intermittent fasting has the backing of scientific research (including a massive 2017 study analysis by the International Society of Sports Nutrition), which suggests that intermittent fasting is just as effective as daily calorie restriction—sometimes better—at improving body composition. Furthermore, intermittent fasting doesn’t involve any calorie counting, and may suppress hunger better than traditional low-calorie diets.

Spending time in prayer and fasting is not automatically effective in accomplishing the desires of those who fast. Fasting or no fasting, God only promises to answer our prayers when we ask according to His will. 1 John 5:14-15 tells us, "This is the confidence we have in approaching God: that if we ask anything according to his will, he hears us. And if we know that he hears us - whatever we ask - we know that we have what we asked of him." In the prophet Isaiah's time, the people grumbled that they had fasted, yet God did not answer in the way they wanted (Isaiah 58:3-4). Isaiah responded by proclaiming that the external show of fasting and prayer, without the proper heart attitude, was futile (Isaiah 58:5-9).

Fasting is the willing abstinence or reduction from some or all food, drink, or both, for a period of time. An absolute fast or dry fasting is normally defined as abstinence from all food and liquid for a defined period. Water fasting refers to abstinence from all food and drink except water, but black coffee and tea may be consumed. Other fasts may be partially restrictive, limiting only particular foods or substances, or be intermittent.