ME TARZAN, YOU JANE
HOW MEN AND WOMEN RESPOND DIFFERENTLY TO FASTING
Our cavemen ancestors lived a very different life to us. There’s debate among anthropological researchers, but it’s generally believed that men were responsible for going out to hunt down dinner, while women stayed at home to look after the cave and the family. When food was in short supply, the hunters would have had to go the extra mile to catch a buffalo (or any other edible creature). They needed to be strong when food was scarce. People who could run fast and fight hard on an empty stomach were more likely to survive and pass on these abilities to future generations.
Some researchers have raised concerns about the effects of fasting on women’s health, in particular their fertility. Intuitively, this view makes sense, because if very little food was available, creating another mouth to feed would have made things even more difficult for those cavemen ancestors of ours. That’s how the theories go, but it’s important that we put them into the context of current research before making specific recommendations.
RESEARCH FINDINGS
Here’s what research has to say:
•In one study by scientists at the National Institute on Aging in the USA, male rats that were fasted intermittently for six months behaved in similar ways to those that weren’t fasted. Their movement patterns and brain performance stayed the same.
•Female rats that were fasted were more alert during their normal sleep times, performed better in mental tests, and tended to move around more. Their adrenal glands (which make stress hormones) also grew.
•Forty-two percent of the female rats that were fasted developed menstrual irregularities, and in 2 percent the menstrual cycle ceased. However, female rats on a low-calorie diet (40 percent fewer calories than they needed, which is equivalent to a 1,200-calories-a-day diet for a typical woman), fared worse – 91 percent of them stopped having a menstrual cycle. This simply suggests that calorie restriction can have a negative effect on fertility.
•Studies on women indicate that fasting could lead to small differences in the levels of hormones that trigger egg maturation and release, although most women maintain a normal menstrual cycle even when fasting for two to three days at a time.
•As already discussed in the “Eat, Fast and Perform Better” chapter, there’s some evidence that women’s muscles respond better to training after eating than when they have fasted, whereas studies suggest that men can perform just as well if they train before eating.
•One study on alternate-day fasting, carried out at Pennington Biomedical Research Center in the USA, observed a reduction in insulin sensitivity and a decrease in glucose tolerance in women, while the response of men’s metabolisms was all positive. However, a more recent study published in the International Journal of Obesity, involving 107 overweight women, found that women who fasted two days a week saw greater improvements in their insulin sensitivity over six months than those who simply cut calories. So, the jury’s still out on this one.
•In other human studies, there don’t appear to be any major differences between how men and women react to fasting.
Put simply, it seems that fasting can help men to run fast and lift heavy things and may help women to think clearly. The downside is that fasting may not benefit fertility, and shouldn’t be combined with a diet based on foods that send blood sugar soaring. But do take note that most of these studies were small – the gender differences in how our bodies respond simply haven’t been well researched.
So, what does all this mean for how men and women should approach fasting?
FASTING FOR WOMEN
Male readers, we are about to get into a bit of girl chat. Keep reading if you want an insight into how the female body works – women love a man who is sensitive to their needs! On the other hand, if you’re more comfortable reading about football and beer, you’ll find that kind of thing on pages 120–34.
As we’ve seen from the research, there’s some evidence that extreme dieting can affect fertility but, notably, human studies suggest that being overweight can affect fertility too. If you’re thinking of becoming pregnant, fasting isn’t automatically ruled out, but it’s important to monitor any changes in your menstrual cycle during fasting and to stop once you are actively trying to conceive.
One key difference between men and women which can affect the response to fasting is the impact of women’s fluctuating hormones on mood and food choices during the menstrual cycle. Understanding the menstrual cycle and how it impacts on cravings, weight gain and mood can be hugely empowering for women.
I’m often asked by women why, at certain times in a woman’s cycle, the scales remain “stuck” – or worse, why several pounds appear overnight – in spite of efforts to eat well. The answer is that the hormonal fluctuations your body experiences throughout the month affect your appetite and fluid retention, which naturally leads to fluctuations in weight.
In the first half of your cycle, the levels of estradiol, a type of oestrogen, slowly rise. Studies suggest that when oestrogen levels are high, appetite tends to be lower. This is one of the reasons why the menopausal transition, when circulating oestrogen levels fall, has been linked with weight gain. It also suggests that a few days after your period could be the best time to begin a weight-loss plan. This is also the best time to consider fasting.
In contrast, the appetite increases after ovulation. Researchers at the University of Ottawa looked at ten different studies of energy intake across the menstrual cycle. They found that women ate 87–500 extra calories a day, on average, in the second half of their menstrual cycle! However, this didn’t have a significant effect on weight because metabolic rate is thought to increase to compensate for extra intake.
An important point to note, though, is that the women studied weren’t actively trying to lose weight. The effects of the menstrual cycle on the rate of weight loss haven’t been studied. Intuitively, it seems likely that a greater rate of weight loss can be achieved in the first half of the month. And it’s important not to be hard on yourself if the scales appear to be “stuck” in the latter two weeks.
Fluid retention is often a factor in weight gain. The reason why women accumulate fluid before their period is unclear but it’s thought to be hormonal. However, eating too many processed foods (high in salt and refined carbohydrates) may make the problem worse, and yet those are exactly the types of food we crave at this time!
THE MONTHLY CYCLE
Being aware of the effects of your menstrual cycle on your weight is the first step to overcoming the difficulties it poses. Let’s look at exactly what happens to a woman’s body, mind and, most importantly, appetite over the course of the 28-day cycle. This information will help you work out when and how to incorporate fasting into your lifestyle in the long term.
DAY 1
Your levels of progesterone (the hormone that builds up your womb lining) and oestrogen have fallen to their lowest levels and your period starts today, bringing relief from PMS symptoms. Drink plenty of water to stay hydrated and relax on the sofa with a warming cup of raspberry leaf or ginger tea.
DAY 2
This first half of your cycle is called the follicular phase and your oestrogen levels are rising. If your period is heavy, eat iron-rich foods – with a source of vitamin C to aid absorption – to keep up your energy. Try a tasty lean beef salad with spinach and orange pieces, sprinkled with sunflower seeds.
DAY 3
It’s normal to feel tired during your period so try to steer clear of sugar this week – otherwise, after the initial blood sugar surge, you’ll feel even more fatigued than you did before.
DAY 4
You may be feeling better, less bloated and want to get more active. Do some energizing, gentle exercise, such as yoga (although don’t do inversions until your period is over), t’ai chi, Pilates or qi gong, rather than intense exercise.
DAY 5
This is a good day to start preparing for your chosen fasting regime. Clear all the junk food out of your cupboards, plan your menu for the week and stock up on healthy ingredients.
DAY 6
Your endometrium (womb lining) has already started to build up again but you should now be feeling less “hormonal”, so today’s a good day to begin fasting. If you’re following the 5.2 Fast, try a 500-calorie day today.
DAY 7
Chances are you’ll be feeling calmer and less stressed now your period is over, meaning cravings should be easier to resist. Use this to your advantage and eat super healthily this week by loading up on fresh vegetables and fruit and saying “no” to sugary cakes and biscuits.
DAY 8
You’re at your least “hormonal” so you may be feeling level headed and prepared to tackle a big project. Cook double the amount of your favourite healthy meals and freeze the leftovers for later in your cycle when your willpower is ebbing. Today is also a good day for your second 500-calorie day if you’re following the 5/2 fast.
DAY 9
You may notice a surge in your energy levels today as your body prepares to ovulate. This is a great week to ramp up your aerobic exercise or even to start a new activity.
DAY 10
Your oestrogen levels are rising, and your body will also produce more follicle stimulating hormone (FSH) and luteinizing hormone (LH), which encourage your ovary to release an egg. Studies on fasting in women have shown a trend toward lower levels of these hormones when you fast, which is one of the reasons you are advised to stop fasting if you are trying to become pregnant.
DAY 11
The dramatic rise in oestrogen before ovulation may make you feel sexier, flirtier and more confident today. Make the most of it by cooking a romantic meal!
If you have a 28-day cycle, your oestrogen levels will reach a peak today. You may notice that your appetite is lower than usual so this is another good day to fast.
DAY 13
You may get slight cramps in your lower abdomen, called Mittelschmerz, as your ovaries are preparing to release an egg. Your ovaries will release about 500 mature eggs over the course of your lifetime – a fraction of the two million you were born with.
DAY 14
You will ovulate around now (your ovaries release a mature egg 11–16 days before your period begins). After the egg is released, it starts its journey down the fallopian tube to the uterus, which takes three to four days.
DAY 15
You may feel a little warmer. This is because your body temperature rises by about 1°C (1.8° F), after ovulation due to raised progesterone levels. Your senses will also be heightened, so indulge in a deliciously sensual meal such as a lean, organic steak or a smooth mushroom risotto.
DAY 16
The second half of your cycle, after ovulation, is called the luteal phase. This is when your progesterone levels rise and oestrogen levels start to fall. Only one small study on fasting has been carried out during the luteal phase. It lowered LH and FSH levels, but it’s normal for these to fall during this phase of your cycle.
Increased progesterone levels this week can cause your bowel to get a bit sluggish. Combat constipation with high-fibre foods, such as beans and lentils, broccoli and cabbage, berries, apples and wholegrains such as whole-wheat pasta.
DAY 18
Your breasts may be feeling tender, and may even have increased in size slightly because your body is producing more progesterone. Although one study on fasting during this phase of your cycle showed there was no effect on progesterone levels, fasting did lower another hormone called leptin, which helps you to feel full. If you’re fasting and find that your appetite is starting to become insatiable, consider limiting your fasts to days 1–15, or incorporating some juices to keep your leptin levels up.
DAY 19
If you’re already dreading those pre-menstrual headaches, cut out chocolate, oranges and red wine in the week before your period. Some people find that corn, wheat and eggs may worsen hormonal headaches, so try cutting down on these just before your period is due.
DAY 20
You may be noticing PMS symptoms today, such as irritability, bloating, headaches and tearfulness. Eat plenty of wholegrains this week – a study found that eating small amounts of wholegrain carbohydrates every three hours and within an hour of going to bed helped reduce PMS symptoms in 70 percent of women. Smoothies may also help.
If you suffer from pre-menstrual bloating, cut down on salt in your diet as salt can cause your body to hold on to more fluid. Steer clear of processed foods and ready meals, which are often high in salt, and drink plenty of water throughout the day to help your kidneys flush more fluid through your system.
DAY 22
Levels of serotonin, your body’s feel-good chemical, may start to fall around now. Snack on a banana, which contains the amino acid tryptophan, a building block for serotonin. Other foods containing tryptophan are free-range turkey, flaxseeds, buckwheat (great for making crêpes) and oily fish.
DAY 23
Avoid making any major decisions or hitting the high street for a shopping session as hormonal changes could cloud your judgement and make you more prone to feeling upset or angry. You’re also more sensitive to pain at this stage of your cycle, so don’t book in any dental appointments, leg-waxing or eyebrow-shaping treatments!
DAY 24
Are you experiencing unbearable cravings for sweet and fatty carbs? Have plenty of healthy, filling snacks to hand – plant-based proteins can be particularly good at beating cravings. Eat crunchy fresh vegetables with a hummus dip or spread oatcakes with low-fat cream cheese, and satisfy a sweet tooth with a dried fruit and nut mix.
Your skin may be feeling greasier and seem more clogged than normal due to lower oestrogen levels which can increase the amount of sebum or oils produced by your skin. Cleanse twice daily with a product designed for sensitive skin and keep up your water intake – aim for around 2 litres (70fl oz /8 cups) a day.
DAY 26
You may start getting cramps a day or two before your period starts. Eat a couple of servings of oily fish this week – studies have shown that women who have a high intake of omega-3 essential fatty acids (EFAs) – found in salmon, sardines and mackerel, for example – tend to have milder menstrual symptoms. EFAs also act as hormone regulators.
DAY 27
Your PMS will be reaching its peak. Add plenty of green vegetables to your shopping basket since they’re high in calcium, magnesium and potassium. These crucial minerals can help calm your nervous system and reduce irritability as well as help to relieve the spasms that lead to painful cramps. A green vegetable juice is also a good idea.
DAY 28
As you wait for your period to start, you may be feeling fragile, both emotionally and physically. Eat warming, comforting foods that are easy to digest, such as porridge, soups with sweet potato or barley, a baked apple or a casserole. Spoil yourself with a cosy evening in and get an early night.
•Start fasting a few days after your period.
•Take note of where you are in your cycle when you weigh yourself. In the two weeks before your period, don’t be disheartened if the scales are stuck or you gain a pound or two. Focus on how your weight is changing from month to month.
•Use body composition scales, which measure body water percentage, as these will help you to identify whether changes in your weight are due to fluid retention.
•Make sure that you have plenty of healthy snacks to hand in the second half of your cycle, in order to avoid binging on sugary, fatty snacks after a fasting period. Prepare chopped veggies in advance, stock your fridge with reduced-fat natural yogurt, and carry nuts or oatcakes in your handbag.
•If you experience sweet cravings, have a fruit smoothie. Smoothies contain a mix of simple sugars and complex carbohydrates. In one study, these were found to reduce the severity of PMS and blunt cravings for sugary, fatty foods. So if you decide to do the 5/2 fast, you could have a smoothie in place of one of your meals.
•If you’re very active, time your workouts in between meals. For example, if you are following the 16/8 fast, exercise during the early evening, before dinner. If you’re following the 5/2 fast, limit exercise on 500-calorie days and wait at least until your breakfast has settled on the following day before working out.
•Take a break from fasting, or switch to a different pattern, if you notice any disturbance in your menstrual cycle.
FASTING FOR MEN
According to the Urban Dictionary, “male fasting” should not be confused with “man fasting”, which is:
“The act of purging the male species from your life in every way for a defined amount of time…”
While this may sound fabulous post-heartbreak or when the World Cup is on, it’s not exactly practical. No, what we are talking about is the fast-becoming-popular world of fasting for weight loss and body shape change by men.
A mate of mine, in the very buff and chiselled form of Alex Smith, lives and breathes an approach to life which could best be described as measured – literally. A personal trainer by profession, Alex is an intense and very potent living proof of what intermittent fasting can do.
Every day, he follows a plan which sees him measure to the gram his nutrients and calories for the day, and the caloric burn of his planned activity. This sounds like serious stuff, no question, but he’s pretty phlegmatic:
“It’s no different than planning what buses or trains you’re going to take!”
Intermittent fasting plays a big role in Alex’s approach:
“Sure, I’m slightly retentive about this, but there’s no question about the results – a planned diet with intermittent fasting applied achieves big results, especially for my male clients who like the defined, scientific, goal-based approach to getting ‘weight loss done’, as many of them put it.”
MEN ARE DIFFERENT!
Ever since Eve chose to lure the characteristically easy-to-persuade Adam in the Garden of Eden, women have known that there’s a whole world of difference between the male psyche and the female psyche when it comes to self-image, eating and approaches to changing said issues.
Says one good friend of mine:
“My husband thinks that his diet is fine, thank you very much. How? Fine means that he has peas with his fish and chips, and onion rings on the side. He says that the rest of his five-a-day comes from grapes, which just happen to have made their way into a bottle of wine.”
My own brother is even worse. His vegetable quota comes from onion rings and potatoes. If you mentioned fasting, like many men he’d think of this as his annual New Year “detox”, which amounts to “going on the wagon” for five days after the excesses of the festive period.
As for body image, asking around a number of younger and middle-aged men, the only thing the former want less of is a lardy stomach, while the only thing the latter want more of is hair on the top of their head.
But it’s wrong to generalize. There’s no questioning the fact that male vanity publishing – think Men’s Health magazine – has had a big impact on men’s self-image and aspirations. In recent years, awareness of the benefits of living healthily has increased and more older men – I call them M.A.M.I.L.s (middle-aged men in lycra) – are participating in public running, triathlon, adventure racing and cycling events. Perhaps it’s just a matter of making dieting a more attractive proposition than meeting down at the community centre each week for a ritualistic weigh-in.
Certainly, if you’re a man under the age of 30, it would seem that dieting is still rarely associated with “things I need to do”. However, dieting for men is coming into its own as a different section of male society – those reaching middle age and gaining responsibilities such as parenthood – contemplate what I will label “the call of mortality”, or, more simply, “the male menopause” (previously known as the “mid-life crisis”). For other men, it’s the unwanted appearance of breasts (“man-boobs” or “moobs”) and an embarrassing belly that spurs them to take action.
In the past, doing something about weight loss might have involved some half-hearted trips to the gym and cutting down on the beer, strategies that were hardly likely to succeed or deliver lasting results. The alternatives involved constant hunger, unappetizing meal replacement shakes and tiresome calorie counting. Fasting, however, provides men with a whole new approach to losing weight and shaping up. It especially appeals to men who are concerned that dieting will make them look puny since a recent study shows that intermittent fasting can preserve muscle mass and even support body-building trends for that Men’s Health “ripped look”.
If you haven’t done so already, read more about the various fasting methods and find your optimum fasting schedule in the “Fit You and Your Life to Fasting” chapter. Careful though, Tiger… Rome wasn’t built in the proverbial day. Many men I know are all-or-nothing, black-and-white types. Fasting can represent a big change for most people, so take it slowly!
THE CHALLENGES OF FASTING FOR MEN
As part of my research I asked a couple of male friends to try out fasting. There were some interesting questions thrown my way:
QSounds great… so by missing a few meals I can look like a men’s fitness cover model?
ANot quite, my eager friend. Fasting requires good food choices, not diving into the nearest fast-food outlet or speed dialling the pizza delivery number at the end of every fasting period. However, my menus and recipes will keep you on the straight and narrow.
QI’m impatient – how long before I get results?
APatience, as I hope your mother told you, is a virtue. The biggest challenge will invariably be breakfast, which to most men is as vital a daily habit as reading the sports pages. Don’t worry, the breakfast pangs subside after two weeks, and you’ll start seeing results in your weight and shape very quickly.
QCalorie counting is not for me
AMany men don’t like the idea of counting calories (seeing this, wrongly, as a “girly” pursuit). If you’re of this persuasion, the 16/8 lifestyle fasting technique is more likely to appeal to you than the 5/2 fast because it’s based on meal skipping rather than counting calories. The 16/8 pattern was popularized by male body-builders and pretty much seems to fit the male mind-set. Alternatively, you could try a short blast of juice fasting to get quick and safe results with no need to calorie count.
QI’m rubbish at sticking with a diet plan. How am I going to manage?
AEven if you’re only restricting or cutting calorie intake intermittently, some of you will find it a challenge, especially if you lead a road warrior lifestyle, love your treats and have a sweet tooth, or work out a lot. My advice is to find simple ways of eating properly, planning meals and then just cutting out certain mealtimes. So long as you follow the nutrition rules you’ll be just fine.