There are four predominant fasting methods, which are collectively defined as a willing abstinence/reduction in food and specific beverages for a period of time. Let’s quickly look at all four methods below and then get into the details of the different intermittent fasting options.
- Alternate Day Fasting = Day of fasting and a day of feeding
- Time-Restricted Feeding (TRF) = Only eat during a specified window of time during the day, which is typically 8 hours long. This is know as intermittent fasting
- 5:2 Diet = Also categorized as intermittent fasting, this diet includes five days feeding and two days fasting per week. You are allowed up to 500 calories on fasting days. This is also know as intermittent fasting
- Prolonged Fast = Several days of fasting done once every several months
I’m sharing about intermittent fasting because this style of diet has a lot of media buzz and I have many clients who are trying it, and you may be as well. I get skeptical when a diet approach reaches vogue level. It’s important to suss out fads from legitimate diet options.
That said, intermittent fasting is promising. Let’s look at some of the known (medically accepted) benefits:
- Promotes blood sugar control by reducing insulin resistance.
- Aids weight loss by limiting calories and boosting metabolism.
- Increases growth hormone secretion, which is essential to metabolism, weight loss, and muscle growth.
- The body is able to induce important cellular repair processes during the fast period, such as removing waste from cells.
There are also other potential benefits, but related medical studies are either not broad enough or research is limited to animals at this point. I’ve listed these possible benefits below:
- May boost brain function and prevent neurodegenerative disorders such as Alzheimers.
- May enhance heart health by improving blood pressure, triglycerides and cholesterol levels.
- Could delay aging and extend longevity.
How does intermittent fasting work?
There are many approaches to intermittent fasting, but the two most common are known as the 16/8 and 5:2 methods. 16/8 fasting involves eating during an 8 hour period and fasting for the remaining 16 hours. Most people on this fast skip breakfast and eat their first meal at noon time and their last meal of the day at 8pm – usually eating three meals during that window.
The 5:2 method includes 5 days of feeding and 2 days of fasting during the week. The idea is to eat a healthy, whole foods oriented diet for 5 days and eat no more than 500 calories during the two fasting days.
From my research, the 16/8 fast appears to be most commonly tried by folks. Interestingly, the benefits of fasting look to be universal whether an individual is fasting on the 16/8 method or doing a very prolonged fast for 2-3 days at a time. By the way, do not try a 2-3 day fast without first consulting your doctor.
The Bottom Line
If you take away all of the health benefits (known and potential) and just look at the impact on total calories consumed during the week, intermittent fasting can be a great benefit because it helps people lose unwanted weight due to the overall reduction in calories. It is certainly a good option for people who are considering different diet approaches.
This plan is most definitely not for you if you have anxiety over periods of complete food restriction, or have not been cleared by your doctor to give it a try.
Photo by Alla Hetman on Unsplash
