Fitness tips: Is intermittent fasting safe?

If you're going to fast, you should still eat right during your "eating window". (Getty images)

Before I begin talking about nutrition, let me just say first that I am a strength and conditioning and lifestyle coach, and I AM NOT a nutritionist. The extent of my experience and knowledge in nutrition is based on the books I read on a daily basis and the seminars on nutrition I attend.

As a coach, we are trained to give nutrition SUGGESTIONS, based on credible information from credible nutritional institutions like the Food and Nutrition Research Institue (FNRI) and other various overseas sources. So the information that I will be sharing to you is my interpretation of what I've read, based from my knowledge of how the body works and adapts through exercise.

Now that that's out of the way, let's talk about about Intermittent Fasting (IF). Yes, a new trend that is developing nowadays is the practice of going for long hours without food (12-16 hours or even more on some extreme cases), in an attempt to lose weight. The proponents reason that this follows the natural course of eating from our "hunter-gatherer days", similar to the also popular Paleo diet, which I wrote about before in my blog.

Simply put, you work your way around a "feeding window", in a day where for 6-8 hours you can eat, while for the remainder of the day, you will be fasting, or not eating (this includes sleep). Another method for IF is to have 24 hours within a week where you don't eat anything. Most of the studies on IF center around these two methods so I won't bother with the more extreme 36-48 hour fasts.

Science says that by going on intermittent periods of fasting, you can improve your overall health and increase weight loss by keeping the metabolism strong and reducing blood glucose and insulin levels. It also lowers all sorts of inflammation and the "rest" you give your digestive system appears to have a positive effect on our enzyme pool. Digestion uses up a lot of enzymes which has been seen to lead to a weakened immune system. So the health benefits are there and it seems, at least through some independent studies and anecdotes, that it can be also an effective weight loss diet.

Before I pass judgement to IF, I had to try it for myself. I followed the rules of the Renegade Diet, which is essentially IF but breaking down the feeding window to under-eating and over-eating phases. I did this for a month, and still continue to do it for some days especially when I find no time for breakfast. One thing about this diet is that it's perfect for late risers and for people who don't like eating breakfast. I also found that I wasn't as hungry as I thought I would be during the fast, although some of my friends who did it as my personal guinea pigs, complained of hunger pangs nearing then end of their fast.

I lost a total of six pounds that month while maintaining my body fat percentage. I also didn't miss a beat with my workouts as long as you time your first light meal just before your workout session. the fuel from the food seems to be enough for me to get a great work out in without any visible dips in performance.

Reading that paragraph alone might get you think that it's effective but I had mixed results from my friends. Although all of them lost weight, some also lost mental focus throughout the day and some were just too hungry to finish the fast. The result was that some of them overate during the feeding window, and what do you usually eat when you're too hungry? Junk.

But the question is about safety, and the jury is still out on this new craze. I personally have seen results but I won't say that it's the diet wonder pill that will solve weight loss. If you do try it, just be careful not to overeat because at the end of the day, if you eat more during your feeding window, compared to a normal three-meal-a-day diet, then you won't be seeing any weight loss. Also, the quality of the food still has to be spot on. Eating burgers and fries during your feeding window is not the right way to do IF.

However, if you're the type of person who likes following diet rules and who is too busy to eat multiple meals during the day, then I'd give it a shot. As long as you keep your food clean and healthy and minimize the junk, then you should be okay. I still think that a disciplined, well-balanced and properly-timed diet is the best eating lifestyle you can adapt, and that with the advancements of science and research, there will come a time when all of this will be either refuted or be replaced by a new food. It was just a couple of years ago that we were recommending 5-6 meals a day, right? That's why the best advice I can give is to eat clean, and eat disciplined. Easier said than done, I know, but so is everything worth doing in life.

Editor's note: The blogger's views do not represent Yahoo! Southeast Asia's position on the topic or issue being discussed in this post

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