Today, I want to talk about intermittent fasting (IF for short). Intermittent fasting is simply restricting your eating for a certain amount of time, and then eating within another window of time. For example, let’s say you fast for 16 hours and then eat for 8 hours. So the question is, how is it beneficial, and should you fast?
Let’s dive in…
Intermittent fasting has many amazing benefits, but like most diet trends, it has become a fad diet. People use intermittent fasting as a magical fat-loss tool (and some claim it’s a muscle-building tool) when it isn’t. Even if you choose to fast, you still need to hit your macros within your feeding window.
One claim of intermittent fasting is that it increases growth hormone, therefore making it a great way to build muscle. The fact that GH increases means nothing other than your body is trying to protect its muscle stores. The role of GH in the scenario is to be anti-catabolic. It has no impact on muscle growth. The tiny anabolic effect that’s shown is not really related to the growth of muscle tissues. The small increase it shows during fasting is no more anabolic than actually eating more food to gain muscle.
Another claim that people make is that insulin is being reduced, so therefore intermittent fasting is magical for fat loss. First of all, insulin is not the devil. Insulin being reduced in a fasting state will never result in fat loss compared to reducing caloric intake so that you’re burning more calories than taking in. Lower insulin levels are basically a by-product of being at a deficit in calories. Fasting is not really superior for fat loss as opposed to a restricted calorie intake.
There are some studies on fasting and the potential negative side effects in relation to athletic performance. Some studies have found that if you compete in a sport such as powerlifting, CrossFit, or any other high-intensity training, your performance may decrease. So, this is something to keep in mind if you’re a competitive athlete. I want to note, however, that it’s a completely personal choice, and that if you find fasting works for you while competing in a strength sport, then by all means go for it.
I also want to address intermittent fasting and the potential hormonal effects it has on women. I have tried intermittent fasting before, and it did not work for me. I ended up gaining weight and feeling pretty crappy. I can’t really tell you the reason why, because there are very few studies on the differences of fasting between men and women. Women’s hormones are highly sensitive to energy intake, so ladies, be cautious if you decide to try IF. I recommend trying maybe a 12- to 14-hour fasting window instead of 16, at least to start.
With all of this said, intermittent fasting is a great tool if you’re in a fat-loss phase of your diet. It restricts your eating to an eight-hour window so that you’ll feel fuller and satisfied when you actually do get to eat for the day. In other words, you aren’t taking in any less calories or burning through fat quicker because of the fasting, but it allows you to adhere to your macros more easily.
However, the flip side of this would be if you’re famished after your fast, and when your feeding window starts, you order a large pizza with a side of chicken wings. This kind of defeats the point of fasting. I’ve seen some people claim you can eat whatever you want while fasting because it magically burns through fat at the rate of a large pizza and fries. Wrong!
Intermittent fasting has some other great benefits. It has been shown to boost immune function (which means less sickness throughout the year), lower inflammation, and improved cognitive function. I also recommend checking out Dr. Jim’s article on intermittent fasting. Jim discusses many of the research studies he has done on intermittent fasting, so I will let him do the talking for that. 😊 There are some great points in there on the benefits of fasting and how to go about it if you’re considering IF.
So again, don’t fall victim to the “fad” part of intermittent fasting as a diet. If you’re considering trying intermittent fasting, I recommend doing your research first.