Intermittent fasting (IF) is currently one of the most popular trends in the health and fitness industry, but is it just an unnecessary method of calorie restriction?
First of all, let’s define IF; it is not a diet, it's a pattern of eating, meaning that it doesn’t change what you eat, just when you eat. There are several different intermittent fasting methods, all of which give definitive eating periods and fasting periods but are all based on the same principles. Perhaps the most popular of which is the 16/8 method; fasting for 16 hours a day with an 8-hour eating window. This is convenient for most as it can be easily done by skipping breakfast and eating between 12-8pm.
Many people feel more alert and productive during a fast, although hunger can be an issue to start with until your body adjusts to this new pattern of eating. No food is allowed during the fasting period, but you can of course drink water and other calorie free drinks. Coffee and tea can also be consumed in a fast despite containing some calories, but as long as you stay under 50 kcals, you should still get the benefits of a fast.
‘But isn’t breakfast the most important meal of the day?’
Yes and no. The jury is out on this one; some people swear by the saying and others (namely IF advocates) couldn’t disagree more. It is now thought that the correlation between obesity and skipping breakfast is simply that breakfast eaters tend to have healthier lifestyles in general, rather than the actual act of eating breakfast. After all, the consumption of calories simply can’t induce fat loss.
1. Weight loss. This is a controversial topic when relating to IF. Intermittent fasting itself cannot cause fat loss. No matter what or when you eat, a calorie deficit is the only thing that achieves this. However, IF is used as a method to easily reduce daily calorie intake and therefore create a deficit without too much hassle. By eating fewer meals, intermittent fasting can lead to an automatic reduction in calorie intake. Additionally, IF changes hormone levels to facilitate weight loss. Because of these changes in hormones, short-term fasting may increase your metabolic rate and further aid fat loss.
2. Reduced insulin resistance. Intermittent fasting can lower blood sugar levels which should protect against type 2 diabetes and induce fat loss.
3. Promotes autophagy. This is the process of cells getting rid of damaged cells, toxins, and waste.
4. Convenience. Simplifying your day of eating with fewer meals to prep, and less to think about!
5. It teaches you to be more in tune with your body. You’ll learn that most of the times you want food, you don’t actually need food, and you’ll be more aware of eating just for the sake of it.
1. If you have an addictive relationship with food, it may not be for you. Going without food for longer spans of time may increase your appetite for more food during the eating window than if you weren’t practicing IF, resulting in overeating and a higher calorie intake. IF is not ideal for binge eaters because it can create a false sense of accomplishment, when the reality is that you are just restricting the times in which you binge!
2. It’s not for everyone. IF isn’t suitable for pregnant women, diabetics or people with low blood pressure.
3. Hormone imbalances. For people who are already quite lean, especially women, IF can lead to hormone disruption which can cause irregular menstrual cycles and reduced testosterone levels.
Whilst it doesn’t appeal to everyone, it can be good practice to do one 24–hour fast, or a trail week of the 16/8 method even if you don't plan on doing intermittent fasting frequently. It's useful to teach yourself some discipline and realise that you'll survive just fine without food for a day. However, if you are considering this type of eating pattern, make sure to discuss it with your doctor before you start skipping meals!