Ways to Make the Fast Diet Work for You

1. Know your weight, your BMI, and your waist size from the get-go

Waist measurement is a simple and important gauge of internal fat and a powerful predictor of future health. BMI is your weight (in pounds) divided by your height (in inches) squared, multiplied by a conversion factor of 703 (or you can just let a BMI website do the calculation); it may sound like palaver, and an abstract one at that, but it’s the best tool we have to plot a path to healthy weight loss. Do note that a BMI score takes no account of body type, age, or ethnicity, and so should be greeted with informed caution. Still, if you need a number, this is a useful one.

Weigh yourself regularly but not obsessively. Once or twice a week should suffice. The mornings after fast days are best if you like to see falling figures. You may discover that your weight is significantly different from day to day. This discrepancy may well be due to the additional weight of food in your system rather than from changes in your fat mass from one day to the next. You may prefer to take an average over several days to arrive at a reasonable figure for any weight loss. But don’t overdo it; try not to make weighing—yourself or your calories—a chore.

2. Chart your progress

If you are someone who enjoys structure and clarity, you may want to monitor your progress. Have a target in mind. Where do you want to be, and when? Be realistic: precipitous weight loss is not advised, so allow yourself time. Make a plan. Write it down. Aim to be specific: if you want to lose weight, there is a psychological advantage in setting a defined goal for how much weight you want to lose (10 pounds?) and by when (March 15 for your sister’s wedding?).

Plenty of people recommend keeping a diet diary. Dieters who write daily notes are known to be more successful at losing weight than those who don’t, with one study finding that it can double weight loss as part of a managed program. Logging consumption seems to heighten awareness; the simple act of quantifying incoming food (and, don’t forget, drink) seems to strengthen your hand. Alongside the numbers and food notes, consider adding your fast day experiences; try to note three good things that happen each day. It’s a feel-good message that you can refer to as time goes by. It helps too, in psychologists’ jargon, to “reframe the motivator.” Rather than thinking “Arrgh, I don’t want to be fat,” focus on “I’d like to be slimmer, healthier, and full of energy.” Consider what you want, frame it positively, write it down, and read it every day.

3. Find a fast friend

You need very few accoutrements to make this a success, but a supportive friend may well be one of them. Once you’re on the FastDiet, tell people about it; you may find that they join in, and you’ll develop a network of common experience. Since the plan appeals to men and women equally, couples report that they find it more manageable to do it together. That way you get mutual support, camaraderie, joint commitment, and shared anecdotes; besides, mealtimes are made infinitely easier if you’re eating with someone who understands the rudiments of the plot. There are plenty of threads on online chat rooms and forums, which are great sources of support and information. Over the past two years, the 5:2 conversation has been evolving and growing online.

4. Prep your fast-day food in advance

Prep your fast-day food in advance so that you don’t go foraging and come across a leftover sausage lurking irresistibly in the fridge. Shop and cook on nonfast days, so as not to taunt yourself with unnecessary temptation. Keep it simple, aiming for flavor without effort. (For simple, sustaining recipe ideas.) Before you embark on the FastDiet, clear the house of junk food. It will only croon and coo at you from the cupboard, making your fast day harder than it needs to be. Eliminate illicit food stashes; empty your snack drawer at work. And don’t forget to check calorie labels for portion size. When the cereal box says “a 30g serving,” weigh it out. Go on. Be amazed. Then be honest. Since your calorie count on a fast day is necessarily fixed and limited, it’s important not to be blinkered about how much is actually going in. You’ll find a quick calorie counter.

5. Wait before you eat

Try to resist for at least ten minutes, fifteen if you can, to see if the hunger subsides (as it naturally tends to do). The idea here is to put food in its place. It’s only food. Once you start to think about food in a rational and realistic way, you’ll discover that you can modify your behavior around it. You can even push it aside. You may discover, as many fasters attest, that you develop a keen sensitivity to your own appetite, hunger, satiety, digestion, metabolism. They will change from day to day. Stay quiet, and you can begin to feel these subtle, visceral things.

On fast days, eat with awareness, allowing yourself to fully absorb the fact that you’re eating (not as daft as it sounds, particularly if you have ever sat in a traffic jam popping M&M’s). Similarly, on off-duty days, stay gently alert. Eat until you’re satisfied, not until you’re full (this will come naturally after a few weeks’ practice). Work out what the concept of “fullness” means for you—we are all different, and it changes over time.

6. Stay busy

“We humans are always looking for things to do between meals,” said singer-songwriter Leonard Cohen. Yes, and look where it’s got us. So fill your day, not your face. As fasting advocate Brad Pilon has noted, “No one’s hungry in the first few seconds of a skydive.” Engage in things other than food—not necessarily skydiving, but anything that appeals to you. Distraction is your best defense against the dark arts of the food industry, which has stationed doughnuts on every street corner and nachos at every turn. And remember, if you absolutely must have that doughnut, it will still be there tomorrow.

7. Experiment

The key, as we’ve established, is to find a plan that works for you, which means you may need to experiment a little until you find your best fit for a sustainable, lifelong plan, not merely a short-lived practice. Rather than think of 5:2 as a “diet,” which in its modern usage is larded with quick-fix connotations, perhaps begin to see it as stemming from the classical Greek “diaita.” This roughly translates as a “manner of living.” A way of life. So, be playful. Customize.

8. Don’t be afraid to think about food you like

A psychological mechanism called habituation—in which the more people have of something, the less value they attach to it—means that doing the opposite and trying to suppress thoughts of food is probably a flawed strategy. The critical thought process here is to treat food as a friend, not a foe. Food is not magical, supernatural, or dangerous. Don’t demonize it; normalize it. It’s only food. Try not to associate fasting with discomfort; be gentle to cultivate the changes you desire; don’t dwell on the downside if, say, a fast day is broken. Move on.

9. Stay hydrated

Find no-calorie drinks you like, and then drink them in quantity. Some swear by herbal tea, others prefer mineral water with bubbles to dance on the tongue, though tap water will do just as well. Plenty of our hydration comes through the food we eat, so fasters may need to compensate with additional drinks beyond their routine intake (check your urine; it should be plentiful and pale). While there’s no scientific rationale for drinking the recommended eight glasses of water a day, there is good reason to keep the liquids coming in. A dry mouth is the last sign of dehydration, not the first, so act before your body complains, recognizing too that a glass of water is a quick way to hush an empty belly, at least temporarily. It will also stop you from mistaking thirst for hunger.

10. Don’t count on weight loss on any given day

If you have a week when the scale doesn’t seem to shift, dwell instead upon the health benefits you will certainly be accruing even if you haven’t seen your numbers drop. Remember why you’re doing this: not just the smaller jeans, but the long-term advantages: the widely accepted disease-busting, brain-boosting, life-lengthening benefits of intermittent fasting. Think of it as a pension plan for your body. So keep your perspective: don’t be disheartened if you “plateau” in any given week; weight loss is your bonus, not your sole objective.

11. Be sensible, exercise caution, and if it feels wrong, stop

It’s vital that this strategy should be practiced in a way that’s flexible and forgiving. If you’re concerned about any aspect of intermittent fasting, see your doctor. Remember, too, that it’s okay to break the rules if you need to. It’s not a race to the finish, so be kind and make it fun.

12. Congratulate yourself

Every completed fast day means potential weight loss and quantifiable health gain. You’re already winning. So? Say so. A study from the University of Chicago reveals how positive feedback on new habits will increase the likelihood of success. Don’t be afraid to grandstand your achievements. Website forums make an ideal platform for a bit of back-patting.