Intermittent fasting, is it healthy or dangerous? Is it easy or hard? Find out what science and experience says.November 22, 2022 4:43 pm July 23, 2018 10:47 am
What actually is intermittent fasting?
Intermittent fasting is the practice of restricting your eating over a specific period of time. It is often used as way to lose weight or boost energy levels.
These schedules are often called ‘cycles’. They’re made up of windows of time when you avoid eating entirely, and others where you can eat normally. Perhaps the most famous ‘cycle’ is the 5:2, also known as the 5:2 diet. In this schedule, you eat normally for five days of the week and limit your calorie intake significantly for the other two days.
However, there are many other variations, including the 16:8 cycle (16 hours of fasting and eight hours of eating per day). The exact schedule a person uses is often tailored to their specific needs, based on their lifestyle and job type. Intermittent fasting is used by athletes and fitness enthusiasts, as well as people who are trying to lose body fat.
Deciphering all the information about fasting
As a method of dieting, fasting has proved quite controversial. Some people rave about its ability to take inches off your waist and boost your energy levels. Others, though, have accused intermittent fasting of being a fad diet. Concerns have also been raised over its long-term health implications.
With any new health trend, there’s always a deluge of (often conflicting) information which can make it hard to evaluate. Sometimes, the best thing to do is to try these things for yourself. An even better option is to read an article about someone who has already done it!
To that end, our intrepid colleague Louise agreed to try intermittent fasting for a month and report back with her findings. We’ll go into Louise’s thoughts on fasting a little lower down, but before that, let’s take a look at what the latest scientific research says..
Does intermittent fasting help with weight loss?
In one academic study, published in JAMA Internal Medicine in 2017, 100 participants, all medically classified as overweight, were each assigned one of three eating regimens.
Some participants were put on what we might call a ‘standard diet’, involving straightforward calorie restriction. They were allowed to eat at any time of day.
The second set were told to alternate fast days. In this schedule, they’d have one fast day followed by a day of normal eating, followed by another fast day, and so on.
The third set were told simply to follow their normal daily eating habits.
Researchers conducted the study over a 12-month period, and the results are as we might expect.
Arriving at the end of the study, both restricted participant groups had lost weight compared with third, non-restricted group. However, the intermittent fasters did not lose more weight than the regular calorie cutters.
Whilst this is only one research study, it seems to show that for weight loss purposes, intermittent fasting is effective. However, it’s no more effective than the regular calorie-restricted diets which have been common practice for many a long year.(1)
Does intermittent fasting improve energy levels?
Other academic research studies have identified patterns between enhanced brain function and fasting.
It is vital to note that much more research is required before this hypothesis can be confidently confirmed, but there are a number of promising results.
Mark Mattson, a neuroscientist and researcher at the National Institutes of Health, has researched why food deprivation might actually increase our energy. He suggests that a variety of evolutionary factors might be behind our boosted energy and enhanced focus when we’re feeling peckish.
Hunger, he says, is an evolutionary reality we need to be able to deal with. When we’re hungry, it’s the worst possible time for us to feel sluggish and tired; rather, we need to get up and about to find a source of food.
“It makes sense that the brain needs to be functioning very well when an individual is in a fasted state because it’s in that state that they have to figure out how to find food,” Mattson told Business Insider. “They also have to be able to expend a lot of energy. Individuals whose brains were not functioning well while fasting would not be able to compete and thrive.”
"Intermittent fasting has been shown to improve energy levels and enhance focus."
So, now we know what scientific research has to say, let’s catch up with our own guinea pig, Louise.
The great fasting experiment
“When researching fasting, I decided I wouldn’t be able to really tell if it was working unless I did it over a reasonable amount of time. I began feeling quite hesitant and skeptical. However, the process was educational, and many of the preconceptions I may have had going in were dispelled over the duration. Nevertheless, many remained.
The most surprising aspect of the process was how easily my body adapted to the hunger.
I chose what seemed to be the most common cycle, the 16:8. This seemed to be the least ‘extreme’ schedule and I was confident I could work it around my professional life. The plan was to eat during a window from 11am until 7pm, and then stop all calorie consumption apart from water and black coffee.
For the first few days, it seemed like my stomach was in constant discomfort during the fasting period. However, this soon changed and my cravings vanished. Towards the end, I even forgot to eat on time, having completed a full fast!
I had also expected my energy levels to drastically decrease due to the lack of nutrition, but they actually remained stable throughout. I had little difficulty completing tasks and including a daily workout alongside the normal demands of my job.
With regard to the weight loss, though, I was underwhelmed. My total body weight went down a tiny bit, which of course is a step in the right direction, but it didn’t seem worth the amount of time and effort I’d put in!”
Should you try it?
Intermittent fasting presents different results in different people. Some believe its use is limited if not pointless, while others claim it has huge health benefits.
The simple answer is: it isn’t clear how beneficial intermittent fasting is. The jury is still out on this one.
From the research, and Louise’s experiences trying intermittent fasting for herself, it seems that fasting for weight loss might not get you the results you’re looking for. If you are looking to lose weight, why not check out our article featuring personal trainer and nutrition coach Cee Fee Dunn? She has worked with many clients over the years who have had weight loss as a primary goal for their workouts and nutrition, and she has some great advice to offer.
That said, you might be one of the lucky people who experience lots of benefits as a result of intermittent fasting. Given that it seems not to negatively affect your energy levels or focus, if you’re curious about fasting, why not give it a try? We’d love to hear about your experiences.