For many years I was a fervent believer in the mainstream fitness mantras of:
1) Always Eat Breakfast
2) Eat multiple meals per day at frequent intervals
The theory being that if you skip meals, your metabolism drops and you’ll gain weight/you’ll get too hungry, crack, and eat a whole box of doughnuts.
Unfortunately, as with so much of the conventional wisdom surrounding health and fitness, it turned out that I’d been led down the garden path yet again.
In our consumerist society, we’re told that if we want to loose fat, we shouldn’t reduce the quantity or frequency with which we consume food, but should simply consume more “health” foods and supplements. Eat less? Feel hunger? No need, just stuff yourself full of Kellogg’s Special K and WeightWatchers ready meals to your heart’s content and all will be well…
For many years I was a slave to this multiple meals per day regimen. I always had to be up super early to ensure time for breakfast, rarely left the house without an array of Tupperware containers, and weekends away had to be planned with military precision to ensure that I’d be able to get my 30 grams of protein at least 6 times per day.
That was until I discovered the revelation that was “Intermittent Fasting”.
Intermittent Fasting (IF) involves going for periods of 16 to 24 hours without eating any food or calorie containing drinks.
Initially I recoiled in horror at the concept of “starving yourself” for 24 hours. Surely this can’t be good for you – What about your metabolism? Surely all your muscles will waste away, then the next meal you eat will all turn to fat!
On the basis that much of what I had been led to believe in the past with regards to nutrition had turned out to be industry sponsored BS (healthy wholegrains/evil saturated fat etc) I decided to give it the benefit of the doubt, do some more research and maybe even give it a go.
The first thing I discovered was that the body does not go into “starvation mode” from simply missing one meal. Studies in humans have shown that metabolism does not start to decrease until the body has been in a fasted state for at least 3 days!
Ok, so I might not lose any muscle, or increase my chances of regaining fat, but what about health, what else might it do to my body?
All the research I came across seemed to point towards positive health benefits.
One of the few universally accepted concepts among scientists is that the one nutritional strategy proven to increase life expectancy is caloric restriction (CR). CR involves restricting calories by around 30-40% from what you would eat by choice, and has been shown to increase life expectancy between 20-30%. Unfortunately such severe caloric restriction also results in irritability and even depression – You live a long and miserable life! Probably why its never caught on…
More recently however, scientists decided to see what would happen if, rather than restricting calories on a daily basis, they alternated between periods of 24 hour fasting, 24 hours unrestricted eating. The results were phenomenal, with IF resulting in less oxidative stress, reduced blood pressure, reduced blood sugar, improved insulin sensitivity, reduced incidence of cancer, diabetes and heart disease, and improved cognitive ability. Unlike CR, however, the IF did not lead to depression. On the contrary it resulted in an increase in brain-derived neurotrophic factor (BDNF), a compound shown to reduce depression and improve cognitive ability. Although the longer term studies have been on animals, numerous shorter studies have been done in humans, all with positive results.
If the science is so conclusive, why have you not heard of IF then? Because unfortunately there is no money to be made from IF! You can’t package it, license it or distribute it, so there’s no point in publicising it or funding the research.
So the science looked pretty compelling, but science is notoriously fallible – in true Primal style I thought I’d take a look back in time at traditional eating patterns to see how IF fitted in.
On investigation I soon realised that we in contemporary western society are the only people that stuff our faces all day everyday, all year round! Fasting has played a major role in all the cultures and religions of the world at some point, and is still prevalent today in many places.
Being an ardent follower of the palaeolithic mode of eating (eating only foods consumed by hunter-gatherers pre-agriculture), it made sense to investigate their eating patters – On reflection, it should have been obvious that hunter-gatherers naturally follow a pattern of IF. Having no fridges, tinned foods or convenience stores, they eat only when they make a kill, or have gathered sufficient produce. Most documentations of HG life indicate they tend to have maybe one small meal of left overs during the day, then a large meal at night after a days (successful) hunting.
By this point I was convinced, so I thought I’d give it a go for myself, as this is really the only way of ever knowing if something will work for you.
The results? Fantastic! Following the IF lifestyle was a totally liberating experience. Having spent years constantly planning multiple meals per day, constantly searching for healthy places to eat while out an about, or having to carry a rucksack full of high protein snacks and veggies around like an Arctic explorer, having the freedom to just not worry about eating until you get home at the end of the day was great.
I wasn’t really looking to make any great changes to my body composition, just to maintain my current levels without the need to eat constantly. To my surprise I actually found that I gained a couple of kilos over the first month (78-80kg), while my bodyfat % had reduced (10%-9%), indicating that I had not only lost some fat, but gained some muscle. This came as quite a surprise, as I’d been eating less protein, less calories, and less frequently than before – The opposite of what you’re “Supposed” to do to add muscle.
Of course, you can never really draw any firm conclusions from an N=1 experiment such as this, there are simply too many variable to control. Perhaps, however it could be attributed to the affect of Human Growth Hormone – A hormone that increases in circulation the longer you fast, which is both anabolic and lipogenic (Check last month’s post on sleep for more details on hGH).
Is IF for you?
I would only recommend IF if you have already been following a primal approach to eating for at least one full month and are totally fat adapted.
If your metabolism is still dependent upon carbs for energy, you will need those frequent sugar fixes to stop you from crashing and burning! Trying to go for an extended period without eating while you are metabolically deranged and unable to burn your own fat stores would not be fun. Before attempting IF, check out the Eat Primal page, and spend 28 days eating Meat, Fish, Eggs and Vegetables. The first week or two will be difficult, but after this transition period you will have turned yourself into a fat burning machine and you’ll be ready for IF.
It is also worth noting that fasting acts as a stressor on the body. While a certain level of acute stress on the body is beneficial (i.e. training), too much stress can be counter-productive. If you’re sleep deprived/stressed at home/work, IF may not be a good idea.
Providing, however, that your diet, training and recovery are all currently in place, I would strongly recommend adding IF into the mix.
Putting it into Practice:
There are numerous ways to implement IF:
1) Condensed daily feeding window
In this method, popularised by @MartinBerkhan on his LeanGains website, you simply compress the time frame in which you allow yourself meals. For example you could eat only between the hours of 13.00 and 19.00, creating a daily 18 hour fast. You can either go the whole distance straight away, or build up starting with 11.00 till 21.00, 12.00 till 20.00 etc.
2) One or two 24 hour fasts per week
Popularised in Brad Pilon’s book Eat Stop Eat, (well worth a read for more in-depth info) this approach involves not eating for 24 hours one or two times per week. Importantly, you still eat something everyday. If you were planning to fast on Wednesday for example, and your last meal on Tuesday was at 18.00, you simply wouldn’t eat again until 18.00 on Wednesday. They key to making this method effective is not going crazy and eating the same quantity of food as usual in one big meal! Just eat one normal meal then push away from the dinner table.
3) Ad hoc fasting
This method involves fasting when convenient. For example you get sent away for the day with work without warning and the only food available is sandwiches and pasta. Rather than trying to improvise a Primal meal by killing the pigeons outside, simply abstain from eating until you return home. Or for example you sleep in, miss breakfast and don’t pack a lunch. Rather than stressing out, or buying some rubbish from the shop, just fast instead.
Whichever method you choose, the key is don’t be to worried about following a precise plan or sticking to a strict regimen.
Personally I find that most days I just have two meals per day, one in the afternoon, one in the evening, but occasionally I will have three, sometimes just one.
Dealing with Hunger:
The first thing is to stop thinking of hunger as a negative thing. This is years of conditioning by a consumer based society. Being hungry makes you more alert, can improve your workout (see below), and means that you’re burning fat.
Another advantage of fasting is that it teaches you what real hunger is, rather than just greed or boredom which tend to be the usual motivators to eat. You’ll find that after a 24 hour fast its proper nutrition that you crave – Steak and Broccoli never tasted so good!
If you’re struggling, plenty of cups of tea and coffee (black no sugar or course) will help you on the way. Also, keep as busy as possible – You’d be amazed at how much you get done on an IF day!
Working out while fasting:
Believe it or not, I’ve had some of my best performances workout wise while fasted! At around the 18 hour mark I feel totally wired and alive with energy, ready to do anything.
Again this makes sense, as in evolutionary terms at this point your body would be getting primed to go hunting. Working out while you’re in a fasted state is the best way to take advantage of the free fatty acids that will have been liberated into your blood stream. To really maximise the results do some HIIT, followed by some lower intensity activity such as easy walking or cycling.
So there we have it, a brief introduction to the IF lifestyle.
Give it a go, and I hope you’ll share the same love for it that I have!