Is intermittent fasting back on the menu? As the Covid-19 crisis creaks onward into winter, its worth bearing in mind that one of the best things you can do for your health whether youre part of an at-risk group or not is to shift a bit of any unnecessary bodyfat youre carrying. Unfortunately, the situation were all in isnt ideal for weight management apart from being at home (and around endless snacking opportunities) all the time, were stressed, anxious, finding it tricky to shop, and prone to overeating.
From a certain point of view, intermittent fasting, in which you cycle through periods of eating and fasting, looks like the perfect solution: rather than needing to plan and prep three meals a day, you can simply cut a few out, without the temptation of meals out with friends to test your willpower. But whats the current state of the science on intermittent fasting? And, more anecdotally, when youre stuck in the house with a stockpile of Weetabix and toast never far away, without a commute or traditional workday to help structure your life, is it actually possibly to stick to it?
Science first. The latest research on IF, in the form of two studies released this year, isnt hugely promising though it might also be informative on the best ways to optimise your own fast. Firstly, nutrition and exercise scientists at Nottingham Trent University, who carried out tests on 14 adult men using the popular 5:2 variation of the diet in which you eat normally for five days a week and restrict yourself to 500 calories on the other two found that participants increased their food intake both the day before and the morning after a calorie-restricted fasting day, as well as reducing their physical activity. Both changes were probably at least partly subconscious test subjects didnt report feeling hungrier, and physical exertion was tracked by wrist-band and the results, say the researchers, were enough for half of the 2,000 calories saved from the restricted eating to be replaced.
In a more recent study, conducted by the University of California, 116 participants who had a body mass index (BMI) that categorized them as overweight or obese used the 16:8 fasting protocol in which you restrict your eating to eight hours a day, typically by skipping breakfast with a control group instructed to eat three structured meals a day and neither group given any guidance on caloric or nutritional intake. After 12 weeks, the researchers found that participants in the fasting group lost an average of about two pounds, while those in the control group lost an average of about 1.5 pounds a difference that the researchers say is not enough to be considered statistically significant while the fasting group also appeared to have lost more muscle mass. Again, study lead Ethan Weiss stressed that the finding was far from definitive but it might have been enough to worry a few body-optimisers whove been using fasting to get lean.
Whats the takeaway? Well, its important to note that neither of these studies were large enough or showed statistically significant enough results to suggest that intermittent fasting comes with a serious downside. But also, the first study in particular suggests that, even if you cheat a bit on non-fast days, you could still cut a couple of thousand calories a week over two cycles of the protocol. And for some people, it undoubtedly works. I like intermittent fasting for some clients, even if Ive not found it to be the magic bullet some claim it is, says personal trainer Zack Cahill. There are some broad claims about it improving insulin sensitivity which there doesnt seem to be much evidence to back up but clients can drop fat very quickly.
Its also possible in lockdown. I did it for six weeks without a break and I think I dropped about a stone and a half, says teacher Chris Warrington. The fat loss was huge initially. My energy levels were solid, but I married it to going to sleep on time and doing more exercise. I didn't change my diet other than cutting out everything after 8pm because I was feasting like some sort of last-days-of-Rome maniac. The biggest issue I had was actually the absence of tea before 12 you notice how much you've been leaning on that stuff. I was on 6-8 cups a day, and going down to 3/4 was a hell of a reduction.
So is it worth a try? It probably comes down to your lifestyle and your habits. The biggest decider for me is: is it something you can cope with well mentally? says Cahill. If I have a client whos going to hate it, of course we dont do it but some all-or-nothing types will love it because its such a simple rule. Others will be watching the clock and waiting to eat all morning. I also always ask clients about their history with food. If someone has a history of disordered eating it strikes me as a bad idea to tell them not to eat.
As with any diet, the question is whether your new way of eatings sustainable but if you can stick to fasting, the results still arent in doubt.
Read more:
Intermittent fasting could be an effective way to manage your lockdown weight - Telegraph.co.uk
