Let’s start with defining what intermittent fasting actually means. Intermittent fasting is an eating cycle where you go from 12-36 hours without consuming food or calorie containing beverages. It is a hot topic right now because many people are using it alone or in conjunction with the keto diet for weight loss.
There are several ways you can fast. Some people will follow a “timed eating” schedule, where they consume all their calories for a day between a specific time, for instance 8am-3pm. Another way to intermittently fast is with alternate day eating schedules where you consume no calories one day and resume normal eating the next. There is also a method where people will eat normally 5 days a week and consume no calories for 2 days a week.
There can be a draw back to fasting. Some people report increased irritability, headache, increased hunger and over-eating or eating the wrong kinds of food on their non-fast days. However, most of the research on intermittent fasting is quite positive.
The idea of fasting has been around for centuries and we, as humans, are designed to eat with our circadian rhythms; consuming our calories during daylight and fasting in the night. Following a diet that involves fasting allows our bodies to use stored glucose for energy, reducing fat.
There is limited scientific data on intermittent fasting but what we have so far does show that it is effective for weight loss, at least in the short term. This could be beneficial for conditions such as high blood pressure, obesity, and diabetes. It is particularly useful for people who do not wish to count calories during the day.
Intermittent fasting may lead to a reduction in blood pressure, cholesterol, triglycerides and heart rate. A study on mice in 2013 showed that intermittent fasting seemed to improve cognition and lessen oxidative stress in the brain.
While the majority of the preliminary findings seem to be beneficial, there are some areas that need further evaluation. Studies on rats, published in late 2018, show that there is some evidence that intermittent fasting may cause a redistribution of fat, specifically increasing stored fat in the abdomen, which could be detrimental for diabetics. There will need to be further studies conducted to see if the findings were accurate and reproducible.
Also, some people find that the timed eating schedule is difficult to maintain. During the limited studies available for review, intermittent fasting did tend to have a high drop out rate.
So, what is the take- away from this article? Well, if you have tried several diets and been unsuccessful, or if you are just the type of person who doesn’t want to be bothered with calorie counting, then intermittent fasting may be for you. As always, you should consult with your provider before beginning any new diet to make sure there are no risks to your health and this blog does not serve as medical advice. (If you want to learn more about intermittent fasting than this blog provides, you can check out “The Longevity Diet”, a book by Valter Longo PhD.)
-Dr. Mike
-Brooke Rieth NP
