Intermittent Fasting: Diet Trend, Health Promoting, or Both?

by Sean Sortor on

Intermittent fasting (IF) is taking the health and nutrition world by storm. And for good reasons too!

It's not a diet. It doesn't dictate what you can, can't eat, or how much to eat. Instead, it describes a "pattern" that involves alternating periods of eating and fasting. Thus, it's only really defining when you should eat.

While this trend has begun more recently, fasting isn't new to humans. It was common in our hunter-gather days when food was not so readily available.

Therefore, eating every 3 to 4 hours and constant snacking are relatively recent habits. And while this eating pattern isn't the only source of our nation's poor health, it may be a contributing factor.

Fasting Patterns

There are several different patterns of fasting used today. The most popular pattern, referred to as 16/8, involves fasting for 16 hours and eating for 8 hours.

For example, you would only eat between the hours of 12:00 PM and 8:00 PM. This essentially means skipping breakfast and no late night snacking.

Other patterns entail:

  • Fasting every other day
  • Fasting two or three days in a row
  • Fasting two days of the week (alternating with eating days)

Potential Health Benefits of Intermittent Fasting

Your body's main source of energy comes from carbohydrates. However, when carbohydrates are not readily available during a fast, your body begins to burn fat for fuel instead.

Other potential health benefits studied include the following:

Weight Loss

Restricting calories is a proven weight loss method. However, it's also a very difficult practice to sustain. Who has time to count and track calories?

This is why many are now turning to intermittent fasting. Assuming you don't overeat when not fasting, you will naturally consume fewer calories when you skip a meal or don't eat for a day.

In fact, three systematic reviews demonstrated that IF is just as effective as conventional calorie restrictive diets when it comes to weight loss.

Insulin Sensitivity

Intermittent fasting has been shown to reduce fasting blood glucose and insulin levels. These effects are known to improve insulin sensitivity as well as protect against type 2 diabetes.

Oxidative Stress and Inflammation

Studies have shown IF may reduce oxidative stress and inflammation. And inflammation is now believed to be the root cause of most modern diseases.

Cardiovascular Health

Intermittent fasting may have a positive effect on LDL cholesterol levels as well as triglycerides. Thus, one's risk of developing heart disease may decrease when these effects are combined with fat loss, increased insulin sensitivity, reduced blood glucose levels, and decreased inflammation.

Is Intermittent Fasting Right for You?

The only way to know for sure is to give it a try. Fasting is generally safe IF you're in good health.

However, before you begin, please consider the following:

Consult with your healthcare provider first. Intermittent fasting isn't for everyone, including those suffering from certain health issues or those taking certain medications. Further, fasting is discouraged during pregnancy and when trying to conceive.

And always consult your doctor if you start experiencing new symptoms once you begin fasting.

Make your meals count. While intermittent fasting doesn't specifically dictate what you should and shouldn't eat, you will not realize the full spectrum of health benefits if you eat a refined and processed diet.

You need nutrient-rich foods to promote good health as well as prevent hunger during your fast. Otherwise, you're sure to overeat and undermine your success.

Be prepared. Make sure you have healthy meals ready to go once your fasting period is over. This will decrease your chances of overeating as well as increase your chances success.

Consider working with a nutrition professional. He or she will make sure you're getting the optimal amount of nutrients as well as provide accountability and supportive encouragement.

To Sum It Up...

Intermittent fasting is a popular trend involving alternating periods of fasting and eating. Science has shown that it is an effective weight loss strategy. It may also improve insulin sensitivity, reduce inflammatory markers, and help to prevent heart disease.

However, intermittent fasting is not for everyone. Before attempting IF, please consult with your healthcare provider and/or a nutrition professional for your safety as well as your success.

References

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Diets that reduce calories lead to weight loss, regardless of carbohydrate, protein or fat content. (2014). Retrieved December 27, 2016, from https://www.hsph.harvard.edu/news/press-releases/diets-weight-loss-carbohydrate-protein-fat/

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