top of page

Intermittent Fasting: Here’s Why

Updated: Jan 31

Fasting has been an important part of cultural, spiritual and religious traditions for thousands of years, so it is certainly not a new fad. Recently intermittent fasting has received a lot of attention, but when you think about it, this is not new either. Our ancestors went to bed not long after the sun went down, and there were no fast food or snack options, so they naturally stopped eating in the evening, and may not have had breakfast until a fire was built and food was cooked in the morning! This gave their digestive systems a rest in a way that was consistent with their natural circadian rhythms. This period of overnight fasting is protective against inflammation and many chronic diseases, like diabetes and heart disease. These days, we have the option of eating from the moment we wake up until the moment we go to bed, and food is always available to grab. Many people never actually feel hunger!

Time-restricted eating is actually what we mean when we talk about intermittent fasting. True fasting, intermittently, for 24 hours once a week, or every third day, or for a weekend once a month, are all valid ways to incorporate fasting into your routine, and also have significant health benefits.

Time-restricted eating means we plan to consume our calories in an 8-12 hour feeding window and fast the remaining hours overnight and into the next morning.

The most common methods for time-restricted eating are:

  • 16:8, in which you fast for 16 hours of the day and limit your eating to eight hours. This might mean breakfast at 11, lunch when it suits you, dinner finished by 7, and nothing but water or herbal tea during the fasting period.

  • 14:10, which is a little more liberal, means fasting for 14 hours and eating in a window of ten hours. This could look like breakfast at 8, lunch at noon, dinner finished by 6 and nothing after dinner but water or herbal teas.

What are the benefits of intermittent fasting and time-restricted eating?

While weight loss is a common motivator, studies show that fasting can have many other benefits: improving metabolic health, improving memory, reducing inflammation, and even extending lifespan. Many people find intermittent fasting reduces sleep disturbances and lessens stomach reflux at night.

Fasting also promotes autophagy, a healthy body process that eliminates old or damaged cells, to be replaced with fresh new ones. Scientists have known for years that when animals eat less food over their lifetimes, they live up to 30% longer!

Research shows that after about 13 hours of fasting, our bodies switch over from burning glucose to utilizing stored fat. When this metabolic switch is flipped, the liver starts converting fatty acids to ketones, which can be burned as energy. Therefore, intermittent fasting is a good strategy for anyone diagnosed with fatty liver as well.

Circadian rhythms are also enhanced by intermittent fasting. Our bodies have cellular clocks, with each organ system having a unique pattern of metabolic activity and rest. In addition to light exposure, keeping our meals in sync with daylight cues strongly promotes better circadian rhythms. This is important, because disrupted circadian rhythms are associated with glucose intolerance, weight gain, poor sleep, reduced immunity, thyroid problems, and many more chronic problems.

By eating in a short daytime window, we eat at the time our metabolism and gut function are optimized for digestion and assimilation. Our digestive systems were not designed to be “on” all the time; the gut was meant to rest and restore at night too!

And speaking of digestion, time-restricted eating also promotes a diverse gut microbiome, which is a very good thing! Some species of gut bacteria proliferate more during feeding periods, while others thrive during a fasting period.

How can you achieve all these benefits? They really kick in after a fasting period of at least 14 hours, meaning a feeding period of ten hours. A pattern of 16:8 may be even more effective for some people. Simply put, it means having dinner on the early side, no snacking after dinner, and then delaying breakfast until mid-morning. It is sustainable and achievable!

Here are some keys for success with intermittent fasting:

• Be as consistent as possible with your eating window. This will help set your circadian rhythms and cellular clocks.

• Don’t eat within three to four hours before bedtime.

• Stay hydrated. It’s OK to drink water or plain herbal tea in your fasting window. There is still some debate if black coffee in the morning breaks the fast or not.

• Pay attention to consuming high quality nutrient-dense foods: count quality not quantity of calories!

• Notice how you feel after a while on intermittent fasting: you may notice lots of subtle improvements in your energy, your digestion and your overall health!

There are times in our life when fasting for more than 14 hours is not recommended:

  • If you are pregnant or breastfeeding

  • For young children

  • If you struggle with an eating disorder

  • If you take medications that need to be timed carefully with meals

13 views0 comments

Recent Posts

See All


bottom of page