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Last Tuesday, I ate some green beans, a Clif bar, and one homemade sous vide egg bite. Thats 500 calories. I swear I dont have an eating disorderits just how you do things on this diet Ive been trying. On Wednesday I was back to my regular 2000-ish calories and feeling fine.
On the 5:2 diet, you fast for two days a week, say Monday and Thursday. You eat 25% of your usual calories on those days. The other days, you eat normally. By the end of the week, youve eaten a similar number of calories as those suckers on 1500 calorie regimens, but you only had to spend two days dieting.
The diet has been wildly popular in the UK for a few years, starting with a 2012 BBC documentary. When I first heard about it, I almost liked the idea. Id previously done a form of intermittent fasting that basically amounts to skipping breakfast and delaying lunch. I focus better in the mornings this way, and I seem to eat healthier overall, but it does take some getting used to.
Fasting for a whole day sounded too hard, but then again, it seems like half of England does it (including Benedict Cumberbatch). I had a few pounds to lose, and I get frustrated and hungry with traditional calorie-counting dietsso I thought Id give the 5:2 a try.
No matter what a diet claims as its raison dtre, lets be real: most people are interested in weight loss. Thats true here too. This diet, as well as others that fall under the intermittent fasting umbrella, is also supposed to improve the function of your brain, heart, metabolism and more.
The appeal is that you dont have to stick to the 5:2 diet for more than a day at a time. Sure, its a rough day, but its nothing like the Whole30 diet, where you commit to a strict set of rules that forbid bread and sugar for a month. And its not the endless slog of a typical calories-in, calories-out diet for long term weight loss, where you need to watch what you eat for months or years.
The first day I tried fasting, I was ravenous by the end of the day. I pulled up Facebook on my phone to distract myself, and my friends were sharing their favorite curry recipes with full-fat coconut milk. I had a pang of jealousy but then thought Hey, I can make that tomorrow. How many diets let you say that on the first day?
The 5:2 diet itself hasnt been rigorously studied, but a close relative, alternate-day fasting, has some data to back it up. Alternate-day fasting works as well for weight loss as traditional diets, according to studies like this one published in Obesity. But it works better for some people than others, and researchers are trying to figure that out, too. One trial published in Obesity Research and Clinical Practice found that white people and older people were more successful on the diet, but there were tons of factors they didnt account for, like whether some groups had better access to healthy foods. Men and women had equal luck on the diet.
The other health benefits, besides weight loss, are not as easy to pin down. Weve long known that mice live longer when theyre underfed. There have been tons of studies trying to figure out what other benefits come from calorie restriction, and whether they can translate to humans in safe and practical ways.
For example, fasting should help your body learn to manage blood sugar better. If you overeat, your cells can become resistant to insulin, eventually leading to type II diabetes. Dieting and exercise both seem to reverse this effect, and from what we know about the way the body manages blood sugar, fasting should help even more. Unfortunately, we dont have enough evidence to say if thats actually what happens.
The book explaining the 5:2 diet, The Fast Diet, is more honest about this than I expected a diet book to be. Author Michael Mosley, a doctor turned BBC presenter, tried several fasting-based diets for his Eat, Fast, and Live Longer documentary. He explains that he settled on the 5:2 pattern as a compromise between the different methods. Essentially, its based on his experience and gut feelings. Im okay with that. We dont have enough evidence to say that fasting (or even dieting) must be done a certain way, so if 5:2 is tolerable and has a decent chance of working, I figure its worth a try.
I wake up thinking about breakfast. Thats not off the menu, but I only have a 500 calorie budget for the day, and Id rather save it for later. So I fill my belly instead with some kind of beverage: coffee, water, seltzer, diet coke. The craving usually subsides.
If it doesnt, Ill go for a snack of veggies, since they are nearly calorie-free. Trader Joes sells a microwave-steamable bag of fresh green beans. With plenty of salt and pepper, its flavorful and almost filling, and the entire bag is just 125 calories. I split it into a morning and evening snack. [Ed note: Ew. Microwaveable green beans for breakfast.]
Either way, Im usually fine until 2pm. If Im having trouble concentrating at work, then I know its time to have some real food. This could be a carefully measured portion of pretty much any food, but I dont see the point in researching recipes, shopping, and cooking up a snack-sized meal. (The Fast Diet has plenty of recipes, though, if you prefer this approach.) More often than not, I choose a Clif bar: around 250 calories, depending on the flavor. I find it about as satisfying as you can expect a 250-calorie meal to be.
I dont get ravenous until evening, and thats the hardest part for me. Ill prowl around the kitchen, debating how to spend my last 100 or 200 calories, making myself even hungrier in the process. I like to have something dense and filling, like an egg bite, but its never enough. Tomorrow, I have to tell myself. I can have more tomorrow.
In fact, its easiest to just stay out of the kitchen and keep your mind off food. Fasting is easiest on the days Im busy at work, and hardest on a weekend when I might have time to lounge around or find myself at a party.
I never tried it, until recently. I just scheduled my workouts and my fast days so they didnt coincide. But yesterday I thought, hey, why not try going for a run and write about how terrible it feels.
It was not terrible. I was shocked: it was afternoon and I hadnt had anything besides Diet Coke and seltzer all day. I brought a Clif bar just in case, but ended up jogging for the better part of an hour without feeling any hungrier than when I was sitting at my desk. I ran at my usual speed, and even ran longer than I had originally planned. (Bad judgment induced by hunger? I wont rule it out.) And afterward, I set the Clif bar aside and didnt have a bite until evening, when I realized I could treat myself to a 400-calorie super burrito.
Some people say they have more energy when they exercise on an empty stomach. I always figured that was something you could get used to, but I didnt expect to experience it on the first try. Maybe it was a fluke. Maybe not.
When its not a fast day, youre supposed to eat normally. Nothing is off-limits, but whether youre using this to lose weight or just a healthy lifestyle, youd be smart to eat your veggies and protein and not too many cupcakes.
I do get a little hungrier the day after a fast (although its easy to skip breakfast, even if I was hungry at bedtime). But theres no guarantee youll end up pigging out. A calorie slash of 75 percent on a fast day generally gives rise to a little more than a 15 percent increase on the following feed day, Dr. Mosley and his coauthor, Mimi Spencer, write in The Fast Diet. They cite this study, which also noted that people feel less hungry on fast days by the second week. (Again, this research is on alternate-day fasting rather than the 5:2 diet).
I find that, mentally, I cant use a diet tracker like LoseIt on my non-fasting days. The tracker has decided I should eat 1,400 calories a day, so on fast days, it tells me that Im doing a good job but also displays a warning that this doesnt seem like enough food. Fair enough. But then the rest of the week, Im tempted to stick to that 1,400 goal, which is not how the 5:2 diet works. I never feel ready for another fast day, because I always felt a little starved. So I ditched the tracker, and easily got back into the 5:2 rhythm.
MyFitnessPal can do different calorie goals for each day, if you pay for a premium subscription. prefer to go without a tracker and let the calories fall where they may.
This definitely isnt the diet for everyone. If youre happy with a plan that asks you to undereat just a little every day, stick with that plan. Youre not missing out on much.
But if you have a hard time sticking to a typical calorie-restriction diet, you might find intermittent fasting easier to take. The 5:2 diet was designed to be a form of fasting that is easy to stick to: you get some food rather than none, and you can schedule your fast days to always fall on whichever days work for you. You can even put them back-to-back if you want, but even Dr. Mosley admits thats too difficult for most people to handle.
The authors note that theres nothing magic about 500 calories (they even allow 600 for men, or just 25% of what you would normally eat). Likewise the schedule: they suggest you cut down to just one fast day a week if youre maintaining your weight, or you can do three fast days if youre having fun and want to speed up weight loss.
They suggest another tweak that I found really helps: doing a 24-hour fast instead of trying to make it through a night, a full day, and then another night. This scheme is so easy Ive found myself doing it by accident. Have a big, late lunch, say around 2pm, and then skip dinner. When you wake up, if you can skip breakfast, then all you have to do is push off lunch until 2pm again, and bingoyouve done a 24 hour fast.
I did lose a few pounds while trying the 5:2 diet, although I didnt do it consistently, and I also also changed some other things in my life around the same time, like exercising more. Im not ready to give the diet full credit, but so far Im happy with it.
Whether this diet works for you will probably depend on how you spend your time (do you have a busy work schedule?) as well as how you handle hunger and willpower. Its definitely doable, and even though its trendy, its refreshingly free of pseudoscientific claims. If youre ready to give it a try, read the ground rules on the Fast Diet website and snoop the forums there to pick up some tips, then pick a busy day and stay out of the kitchen.
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Read more here:
Starving Yourself Two Days a Week Is Actually Not a Bad Diet - Lifehacker Australia
