The pros and cons of intermittent fasting

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For most people, the word fasting brings up the notion of prolonged periods without food or maybe even drink. Some people fast periodically for religious reasons or medical necessity (say, before a procedure). But a new type of diet has people fasting to lose weight, improve health, live longer (and healthier), boost mental clarity, and more. Here’s what you need to know about this trendy fast.

Intermittent fasting may be practiced in a few different ways, according to research on the subject:

  • Alternate day fasting is just what it sounds like. On alternating days, you either feast or fast.
  • Modified fasting, also known as 5:2 intermittent fasting, involves eating normally five days a week with food restricted to about 25% of your calorie needs on two non-consecutive days. (Think: around 500 calories or less on restricted days.)
  • Time restricted fasting limits food within specific time windows, say 8 PM to 10 AM. In this type of fasting, you go 12 to 16 hours restricting food.

Will you lose weight?

These forms of fasting do appear to promote weight loss, according to a review study published in August, 2017. However, the science is thin among humans and typical studies involve small sample sizes and limited durations. Still, the outcomes suggest that people do lose weight so if you want to give it a go, here’s what you should know.