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Intermittent Fasting

Intermittent Fasting

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Intermittent Fasting infographic
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Intermittent fasting involves a period of controlled fasting to help you lose weight and improve your metabolism.

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How to Do It

There are three primary methods of intermittent fasting involving daily or near-daily fasting:

  • Alternate-day fasting - This regime switches between days with no food restriction with days of extreme restriction consisting of one meal that provides 25% of your daily calorie needs.

Example: Monday, Wednesday, Friday are fasting days, Tuesday, Thursday and Sunday have no calorie restrictions.

  • Whole-day fasting - This regime involves 1 or 2 days a week of food-restricted fasting (consuming 25% of daily calorie needs), with no restrictions for the rest of the week.

Example: 400 calorie diet Monday, Tuesday, with no restrictions for the rest of the week. It is also known as the 5:2 diet.

  • Time-restricted feeding - A daily regime involving eating meals within a specific time frame and fasting for the rest of the day.

Example:  Fasting for 16 hours in a row and eating 2-3 meals during an 8-hour “window.” It is also known as the 16:8 diet.

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  • May encourage weight loss
  • May increases metabolism
  • May Potentially improves certain disease risk factors 
  • May make you more sharp and alert 
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Time Commitment

A lifestyle commitment that once established, doesn’t require any extra time.

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Why it works

  • Reducing meal frequency results in fewer calories being consumed, which helps accelerate weight loss.
  • Calorie restriction may improve tolerance to metabolic stresses, with the stress of the fasting possibly causing an immune response that repairs cells and causes positive metabolic changes such as reduced blood pressure and blood glucose [1], [2].
  • Nightly fasting may result in long term metabolic health improvements by modifying gut microbiome [2], [3].
  • Cellular stress from fasting may affect signaling pathways to enhance mitochondrial health, DNA repair, and metabolic health [4].
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Suggested Frequency

A daily regime

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Side Effects

  • Before settling into intermittent fasting, you may feel hungry, tired, and irritable.
  • Headaches can be common with starting intermittent fasting, so be sure you’re consuming enough water during eating and fasting periods.
  • Heartburn can be a side effect due to an empty stomach; time will likely solve this.
  • Cold fingers and toes can be a common side effect due to lower blood sugar and blood flow.
  • Dizziness due to low blood sugar while getting used to fasting.
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Required Equipment

Meal schedule

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Gurus/Celebrities/Doing it

Dr. Terry Dubrow

Hugh Jackman

Terry Crews

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Related Products

Meal planner

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Suggested Time of Day

The most popular 16:8 regime typically places its eating window from 11 am to 7 pm.

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  • Because intermittent fasting withholds food, those with conditions that need food at regular intervals, such as diabetes, should not undergo intermittent fasting.
  • Those at risk of eating disorders would be advised to avoid because of the focus on food restriction.
  • Those with high caloric needs, such as pregnant or breastfeeding women, should also avoid intermittent fasting.
  • Most side effects are a result of getting used to your fasting regime and should stop with time.
  • It is always a good idea to consult a doctor if you are worried about how intermittent fasting will work for you.

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 AntiAging  Fitness  Productivity  Focus  Creativity  Memory  Sharpness
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