The Fast Diet: The secret of intermittent fasting � lose weight, stay healthy, live longer (11 page)

Whatever you eat on a fast day (or any day), the most important thing is to relish it. Go slow. Have a look at the menu plans on pages 139-61 for more ideas.

There is some debate as to whether vegetables are best eaten raw or cooked; cooking may, as raw-foodists contend, destroy vitamins, minerals and enzymes, but it also softens cellulose fibres, making nutrients more available for take-up in the body. Lycopene, a potent antioxidant found in tomatoes, is boosted in cooking.
³⁹
A small blob of ketchup is no bad thing. Meanwhile, boiled or steamed carrots, spinach, mushrooms, asparagus, cabbage, peppers and many other vegetables also supply more antioxidants, such as carotenoids and ferulic acid, to the body than they do when raw.
⁴⁰
The downside of cooking veg is that it can destroy their vitamin C. The raw versus cooked argument is a complicated one. Our best advice? Eat plenty of vegetables, just the way you like them.

Yes. Counter-intuitive as it may seem, no foods are off-limits, none proscribed. On the five days a week when we’re not restricting calories, we both eat freely – fish and chips, roast potatoes, biscuits, cake. The Illinois study certainly found that volunteers encouraged to eat lasagne, pizza and fries during ‘off days’ still lost weight.

Even so, don’t try to gorge in a bid to make up for lost time, like a contestant in a blueberry pie contest. You could compensate for fasting by grossly overeating the next day, but it’s very hard to do and you probably won’t want to; a calorie slash of 75% on a fast day generally gives rise to little more than a 15% increase on the following feed day.

This absence of hyperphagia (excessive appetite) on a non-fast day surprised the research team: ‘We hypothesised that the participants would increase their energy intake on the feed day by approximately 125% of their baseline needs. However, no such hyperphagic response was observed… On average, subjects were only consuming 95(±6)% of their calculated energy needs on the feed day. This change in meal pattern helped these subjects to achieve a marked degree of energy restriction (37% net daily), which was related to the pronounced weight loss attained (5.6kg in eight weeks). These preliminary data suggest that subjects are not likely to consume higher fat diets on the feed day when partaking in an ADMF regimen.’
⁴¹

Humans have, however, evolved to prefer calorie-rich
foods – it once gave us an edge – and perhaps the greatest advantage of the Fast Diet is that it expressly includes ‘pleasure foods’, on five days of the week. For most of the time, there is no limitation, no deprivation, no guilt. The psychological impact of not being denied is huge; it frustrates what’s known as the ‘disinhibition effect’ – a paradox in which designating certain foods ‘off limits’ makes us likely to eat more of them.
⁴²

Remember, then, that this is not a cycle of bingeing and starving: it is calibrated and moderate. Studies and experience show that Intermittent Fasting will regulate the appetite, not make it more extreme. You could pig out on your non-fast days, working your way steadily through all the ice-cream flavours in the freezer. (Even if you did, you’d still get some of the metabolic benefits of fasting.) But you won’t do that. In all likelihood, you’ll remain gently, intuitively attentive to your calorie intake, almost without noticing. Similarly, you may find yourself naturally favouring healthier foods once your palate is modified by your occasional fasts. So, yes, eat freely, forbid nothing, but trust your body to say ‘when’.

Dieting lore has long suggested that breakfast is the most important meal of the day – miss it in the morning and it’s like leaving the house without a coat. But that’s not necessarily the case. Recent research shows that a bigger breakfast begets a bigger lunch (and a bigger dinner),
which – no surprises here – means a higher overall calorie count for the day.
⁴³
Some fasters find that they need sustenance to start the day, others may prefer to wait until later to ‘break their fast’. It’s up to you, and whichever pattern you choose may change over time.

Plenty – as long as it doesn’t have a substantial calorie content. In practice, as with most decisions on the Fast Diet, the choice is entirely up to you. Drink plenty of water – it’s calorie-free, actually free, more filling than you think and will stop you confusing thirst for hunger. In summer, add rounds of cucumber or a dash of lime. Freeze it and suck on cubes. If you want warmth, miso soup contains protein, feels like food and clocks up only 84 calories per cup; vegetable bouillon pulls off the same trick. If you find it hard to sleep, a mug of instant
low-cal
hot chocolate is under 40 calories and a comforting thought.

During the day no-cal drinks are best. Hot water with lemon is a standby favourite for fasters, but you might prefer to add mint leaves or a scattering of cloves, a slice of ginger root or some lemongrass. If you are fond of herbal teas, try some unfamiliar flavours to spice up the day (liquorice and cinnamon, lemon grass and ginger, lavender, rose and chamomile…) Green tea may have health-giving antioxidant properties (the jury’s out), but if you like it, drink it.

On fast days we drink our tea and coffee black and sugarless; if you prefer it with milk and artificial sweeteners, fine. But beware that the calories in milk add up, and what you are trying to do is extend the time you are not consuming any calories at all.

While fruit juices are seen as healthy, they generally have a surprisingly high sugar content, are lower in fibre than a whole fruit and can rack up the stealth calories without so much as a by-your-leave. Commercial smoothies can have a similar sugar content to Coke and, because they are acidic, they are corrosive to your teeth; they are also loaded with calories. If you need flavour, swap juice and smoothies for very dilute cordials – perhaps a dash of elderflower with fizzy water and lots of ice.

Alcoholic drinks, though pleasant, merely provide ‘empty’ calories. One glass of white wine contains about 120, while a 550ml can of beer has 250. Unless you really can’t say no, abstain absolutely on a fast day – it’s a golden opportunity to slash your weekly consumption without feeling serially deprived. Think of it as an alcovoid, for two achievable days each week.

There’s a growing body of evidence to suggest that – far from being a guilty pleasure – drinking coffee may be good for you, helping to prevent mental decline, improve
cardiac health and reduce the risk of liver cancer and stroke.
⁴⁴
So go ahead, drink coffee if that’s what gets you going and keeps you going each day. It’s a useful weapon in your arsenal against boredom, and coffee breaks can pleasantly punctuate your day. There’s no metabolic reason to avoid caffeine during a fast, but if you have trouble sleeping, limit your intake later in the day. You should, of course, drink it black. A 16 fl oz caramel macchiato has 224 calories… Just saying.

The general idea of the Fast Diet is to give your body an occasional holiday from eating. Let your mouth rest. Give your belly a break. If you must snack on a fast day, do it with awareness and frugality, always keeping a weather eye on the GI:

You knew that chocolate bars were hardly a health food, but did you know how sugary rice cakes and fruit bars can be? Bear in mind that processed foods tend to have hidden sugars and, though convenient, won’t give you anything like the nutritional advantage of good
old-fashioned
plants and proteins. Try carrot or celery sticks with hummus, or a handful of nuts – always factoring them into your daily calorie count (don’t cheat).

Habitual snacking, even on low-calorie, nutrient-rich foods, is not advised; part of the motive here is to retrain your appetite, so don’t overstimulate it. If your mouth is desperate for attention, give it a drink.

A number of people say that commercially available
meal-replacement
shakes helped them through the first, and normally hardest, weeks of an intermittent fast. Arguably, shakes are simpler than calorie-counting, and on your fast day you could simply sip away when waves of hunger strike. We are not great fans as we think real food is better. But if you find it helps, by all means try it. It’s best to go for brands that are low in sugar.

To clarify: this is a book about fasting, the voluntary abstention from eating food. The reasons why this is good for you go way beyond the fact that you are simply eating fewer calories. They arise because our bodies are designed for intermittent fasts. As you’ve seen, the scientific term is hormesis; what does not kill you makes you stronger. So while starvation is bad, a little bit of
short, sharp, shock food restriction is good.

Your aim, then, is to carve out a food-free breathing space for your body. Going to 510 calories (or 615 for a man) won’t hurt – it won’t obliterate a fast. Indeed, the idea of slashing calories to a quarter of your daily intake on a fast day is simply one that has been clinically proven to have systemic effects on the metabolism. While there’s no particular ‘magic’ to 500 or 600 calories, do try to stick resolutely to these numbers; you need clear parameters to make the strategy effective in the medium term.

Having ‘an extra cookie’ on a fast day would be antithetical to your goals (not to mention the fact that it would probably spike your blood sugar and eat up most of your allowance in one buttery bite); when you’re fasting, you need to think sensibly and coherently about your food choices, following the plan laid out here. Exercise will-power, reminding yourself that tomorrow is on its way.

The Fast Diet is an intermittent method, not a deprivation regime, so your nutritional intake from a wide variety of food sources should remain relatively steady over time, providing all the vitamins and minerals you require. If, as recommended, your fast-day foods centre on protein and plants, they’ll give you all the goodness you need so you won’t have to resort to costly bottled multivitamins. Do, however, choose your fast-day foods with care, ensuring
that, over the course of a week, you consume adequate B vitamins, omega 3s, calcium and iron. Be sensible and eat well. While we are not fans of bottled vitamins and minerals, if a qualified health professional has suggested a particular supplement, you should continue to take it.

Why not? In the interests of flexibility and normality, there’s no reason to change your usual pattern of activity while fasting. Research demonstrates that even a more extreme three-day total fast has no negative effect on the ability to perform short-term, high-intensity workouts or long-duration, moderate-intensity exercise. Athletes seem to suffer no loss in performance during occasional fasting; a 2008 study of Tunisian footballers during Ramadan found that fasting had no effect on performance (‘Each player was assessed for speed, power, agility, endurance, and for passing and dribbling skills. No variables were negatively affected by fasting.’)
⁴⁵
In fact – and this is worth noting if you are aiming for optimal fitness – training while fasting can result in better metabolic adaptations
⁴⁶
(which means enhanced performance over time), improved muscle protein synthesis,
⁴⁷
and a higher anabolic response to post-exercise feeding.
⁴⁸
,
⁴⁹

Training on an empty stomach turns out to be beneficial on multiple levels, coaxing the body to burn a greater percentage of fat for fuel instead of relying on recently consumed carbs; if you’re burning fat, don’t forget: you’re
not storing it. As we’ve seen, one recent study found that working out before breakfast is beneficial for metabolic performance and weight loss.
⁵⁰
A report in
The New York Times
suggests that it even ‘blunts the deleterious effects of over-indulging’ – making fasted exercise a canny way of ‘combating Christmas’.
⁵¹
According to the study’s authors, ‘Our current data indicate that exercise training in the fasted state is more effective than exercise in the carbohydrate-fed state.’ Certainly food for thought. Do not, however, increase your fast-day food allowance to ‘compensate’ for calories burned through exercise: on a fast day, stick to 500 or 600 calories, whatever level of activity you choose. That’s where the benefits lie.