What is it?
Intermittent fasting involves shifting when (but not necessarily what) we normally eat; it’s essentially a pattern that cycles between periods of fasting and periods of eating. This differentiates it from a ‘diet’ in the traditional sense. What’s great is that it emulates habits which were common in human history, since we have evolved from functioning without food for extended periods when food wasn’t available.
How can I do it?
There are different ways to approach intermittent fasting. All follow the same pattern of splitting days and weeks into eating and fasting periods. The most popular method is 16/8, which involves restricting your daily eating period to 8 hours (e.g. 9-5pm) and fasting for the other 16. It’s entirely your choice when this 8-hour window is, making it sustainable and easy to stick to.
Almost just as popular, 5:2 involves drastically restricting calories on two non-consecutive days of the week (‘fast’ days), but eating a normal quantity of food the other five days. However, the disadvantage of this method is you’re likely to feel hungry on fast days. To fight the hunger pangs on 5:2, make sure you’re eating plenty of fibre (think wholegrains, fruit and veggies) and lean protein (fish, eggs and chicken are great examples), both of which help keep us feeling fuller for longer.
Note that it may take some time for your body to adapt to this different way of eating, so try easing into intermittent fasting. Many people consider 16/8 the simplest method; you might want to try this first and, if you find it easy and feel good during the fast, then maybe try moving on to 5:2. However, you don’t necessarily need to follow a structured intermittent fasting plan to potentially gain at least some of the benefits. Experiment with different approaches and find something that you enjoy and fits your schedule.
What is it used for?
Whichever method you use, intermittent fasting could be an effective weight management tool; there are even indications that it results in less muscle loss than the classical approach to dieting. However, it’s important to remember the main reason for its success is that intermittent fasting can help manage or reduce total calorie intake. Therefore, avoid binging during your eating periods, as you may not lose weight.
Alongside the potential weight loss benefits, intermittent fasting has also been suggested to help improve overall health. For example, it initiates important cellular repair processes including autophagy, where old and dysfunctional proteins that build up inside cells are removed, and reduces markers of inflammation. This can help slow aging and the development of some chronic diseases. Human Growth Hormone (HGH) increases when fasting, while insulin and blood sugar decrease. Together, these changes may increase your metabolic rate, help reduce your waist circumference, and protect against the development of type 2 diabetes.
When to avoid it
Intermittent fasting is not suitable for everyone; for example, those who are underweight or have a history of eating disorders. There is also some evidence that intermittent fasting may not be as beneficial for women as it is for men. Moreover, anecdotal reports suggest it can cause menstrual periods to suspend until normal eating patterns are restored. Therefore, women should be careful with intermittent fasting, especially If you have issues with fertility or are trying to conceive. Intermittent fasting is advised against if you’re pregnant or breastfeeding and, if you have a medical condition (e.g. high cholesterol or diabetes) you should consult with your doctor before adopting this eating pattern.
Intermittent fasting may help in managing your health. However, eating minimally processed, whole foods, exercising and getting adequate sleep are still the most important factors to focus on for the general population. There is no one-size-fits-all solution when it comes to nutrition and, whilst intermittent fasting may be great for some people, it may not be for others. If your interested seek advice from your healthcare professional.