One of the fasting growing trends in weight loss is intermittent fasting. It means not eating for a scheduled period, either daily usually for up to eight hours, or eating normally for five days and fasting entirely for two days.
There are reported health benefits, but it is very controversial, mainly since all of the reported health benefits result from weight loss in general and are not specific to intermittent fasting—for example, lower blood pressure, better cholesterol, body fat loss etc.
While the benefits may not be unique, there are some specific risks for some people, so any person thinking of this diet must do so with medical supervision.
Regular food intake plays a vital role in the metabolism of medications, as does fluid intake. Additionally, the body’s insulin production, in part as a response to carbohydrate intake and thus not having any food for eight hours, can play havoc on a person who already has pre-existing issues. For this reason, please talk to your doctor before starting intermittent fasting in any form.
What about the evidence to support it? The first question that needs to be asked is: Is it sustainable?
Diets that involve starting a significant shift in your eating habits, followed by losing the expected weight, then resuming prior eating habits are senseless, counterproductive and medically dangerous because up and down weight loss and weight gain contribute to high blood pressure.
The only “diet” that makes sense (criteria I have observed required common sense, which is sometimes in short supply) is an eating pattern that is part of a healthy lifestyle for the rest of your life.
The most significant cause for concern for the safety and impact of intermittent fasting is the lack of research.
Most of the studies have been on mice, not men. An excellent German study took 150 participants and divided them into three groups: group A fasted for eight hours per day; Group B fasted for two days per week; Group C was asked to try and eat healthily and reduce calories. All of the subjects were obese.
After 38 weeks with close monitoring, the results were that there were no statistical differences between the groups. All of the groups lost body fat. Those subjects who lost five per cent of their weight had huge benefits: visceral fat dropped by 20 per cent, and liver fat dropped by 33 per cent.
This study agrees with another review of a wide range of diets that showed no difference between any combination: low fat, low carb, keto, high protein, etc. Here is the explanation: the success at long–term fat loss was determined by the person’s ability to stick to a plan and not fall off the wagon. For this reason, I have always recommended a balanced, varied diet that is enjoyable and sustainable- specifically the Mediterranean diet and the Asian diet – preferably a combination of the two.
The one thing that is 100 per cent predictable is that the current fascination with intermittent fasting is that there will be a new fad in a year or two. Meanwhile, the people living in Japan, China, Okinawa, Italy, Spain, Greece will all be sitting back enjoying the same food their great grandparents ate and paying no attention to the newest marketing blitz.
Ron Cain is the owner of Sooke Mobile Personal Training. Email him at email@example.com or find him on Facebook at Sooke Personal Training.