Firstly apologies for being out of contact for so long. I’ve been working on a new book about diet and fitness (with the not very imaginative provisional title of ‘Diet and Fitness Explained’). It’s been enjoyable and interesting to write but fitting it around a full time job and a family has been difficult. It is now very nearly complete and current indications are that it is likely to be released some time in mid to late May (the audio version is likely to available around August time).
It is intended to shed new light, and give some new perspective, and hopefully a good overall understanding, of the whole diet and fitness phenomenon. I hope it does this.
Below is a sample Chapter that deals specifically with the digestive system. Other Chapters break down ‘hunger’ into its constituant parts and analyses each part, and deals with which foods we choose and why, and most importantly why we seem to want the foods that are worst for us, and how we can go about changing that.
I hope you find it interesting.
There has been an advertising campaign in the UK stating that obesity is the second highest cause of preventable cancer after smoking. I do not agree with this. Obesity isn’t a cause of cancer, it is as symptom of overeating, and in particular eating the wrong food. Cancer is also a symptom of the same thing. It is overeating and eating the wrong type of food that is the problem, and a problem that causes both obesity and cancer.
We seem to have this rather strange view of overeating, we know it causes us to become overweight and can cause health problems (like diabetes and cancer) but other than this we don’t see any downside to it. The actual immediate negative impact is largely ignored.
In fact digestion itself takes a huge amount of effort. How much of an effort depends on the food we eat. Our bodies find it easiest to process liquids rather than solids, so food with a high water content and a high fibre content (such as fruit and vegetables) are far easier to digest. It helps to have a basic understanding of how digestion works so you can fully appreciate the effort involved.
Once in the stomach, chewed food has to be churned in order to mix it with various digestive enzymes. This churning process is hard work and to undertake it the body redirects a large portion of the blood supply from the muscles in the extremities to the stomach and intestines. This is why we often feel tired or drained after eating a large meal, and why it is not unusual to sleep after a large meal.
After the stomach is through churning, the partially digested food is moved into the small intestine where it is mixed with more digestive juices. Some nutrients are absorbed at this stage then the remainder is passed into the large intestine. There, water and the vital mineral salts dissolved in that water, are extracted and absorbed into the blood stream through thin permeable membranes. The final residue is squeezed along the length of the large intestines and passes out of the story.
The process by which food moves through your digestive tract is known as peristalsis. The organs of your digestive system contain a layer of muscle that enables their walls to move. The muscle behind the food contracts and squeezes the food forward, while the muscle in front of the food relaxes to allow the food to move. The total distance this food has to move is 30 foot. There is 30 foot of digestive tract for it to cover, every inch of which it has to be pushed through by the digestive muscles.
If the food we are eating is difficult to digest then all of this takes a huge amount of effort and while it is taking place we feel drained and tired. As you can imagine although it leaves us feeling tired, and we are tempted to sleep, the sleep we get when digesting food is not good quality sleep. Digestion not only takes a huge amount of energy, it also creates a huge amount of movement and a frenzy of activity. This internal churning, movement and activity disturbs our sleep with the result that we tend to need to sleep longer and feel less refreshed when we wake up. Also, as any physicist will tell you, all energy ultimately ends up as heat energy, so the process of digestion tends to make us warm, which is another thing that disturbs sleep. Lots of the drugs we take on a regular basis tend to disturb our sleep (this is dealt with in more detail in a later chapter) but if you are seem to be tired all the time, and find you wake up at night hot and uncomfortable, you may find changing your eating habits works. Needless to say smaller, lighter meals (and by lighter I mean a greater proportion of easily digestible food, or food with a high water content like fruit and vegetables) is far less effort for our bodies to digest, and making sure you have your last meal several hours before going to bed also helps.
So overeating and bad diet doesn’t just cause us long terms problems like cancer and obesity, it also causes us short terms problems like lethargy and sleep disturbance (particularly if you, like many people, tend to eat a lot in the evening before going to bed). This is a less well known but (for me at least) a far more important impact of overeating and bad diet. Let me be clear on this point, I am not saying that cancer and obesity is worse then lethargy and disturbed sleep, but for me the short-term implications always weight more heavily than the long term implications. Everyone dies, and what happens to me in 20 or 30 years simply has less consideration for me that what happens to me today and tomorrow. This may seem incredibly short sighted and irresponsible of me, and maybe it is, but it is what it is. If you offer me a pleasure today but tell me it may have a detrimental effect in 30 years, I’ll take the pleasure and worry about 20 or 30 years time in 20 or 30 years time. But if that pleasure is fleeting and lasts only for a few seconds, and the detriment will be felt a few minutes after that, and will last all night and into the following day, AND will impact me in 20 or 30 years then there’s no contest. I’ll forgo the pleasure and not worry in the least about it.
Another point to bear in mind with indigestible food (like pizza, burgers, red meat and processed foods like pasta and bread) is that because your body cannot easily digest it the muscles of the digestive system have to work extremely hard to process it. This requires energy, energy that your body is struggling to extract from the rubbish you have just eaten. It needs an immediate and readily available and readily absorbable hit of energy, so you will crave something sweet, something with refined sugar. This is why if you overeat savoury food you can be so full you can scarcely move, be so full you feel physically sick, but still crave something sweet. It’s the body crying out for readily available energy. This is why you often crave something sweet after a large, processed food based meal.
The knock on problem with this is that your body cannot dedicate enough energy to processing the rubbish you’ve eaten, you will feel tied and lethargic as your body struggles to get to grips with it but there is nothing it can really do. It needs to focus far more of your bodies resources to doing this. So how does it do this? It waits until you are asleep, then it really gets to work on it. This is why so many people evacuate their bowels first thing in the morning; it is because their body has worked on the food overnight. The problem with this is not only the effect on sleep which we have already covered, but also that your body is then extracting the vast majority of the huge number of empty calories from what you have eaten whilst you are asleep. As you are not actively moving at this time these calories are far more likely to be stored as fat. Contrast this with fruit and vegetables which are far easier to digest and have readily available energy, but energy that is released slowly so you can actually use it.
This is why you have these well documented cases of people who consume way over their recommended daily intake of calories in fresh fruit and vegetables, and yet are slim and healthy looking, whereas people who consume far less actual calories in the form or processed, nutrient sparse, low fibre and low water content food will pile on the weight.
This is a key point that is worth keeping at the forefront of your mind because it can be confusing. There is all the difference is the world between the ‘slow release’ and ‘indigestible’. ‘Slow Release’ means the energy is absorbed slowly so we don’t get the spikes and lows or hunger straight after. Slow release energy is found in fruit, vegetables, nuts, legumes, oats etc. It is very easy for your body to digest this sort of food (indeed it is precisely what your body is best able to process), it is just that the energy boost from it is gradual and long lasting. ‘Indigestible’ means your body struggles to digest it. We are often told that ‘slow release’ is best, and this is correct, but then we assume (understandably) that something that is difficult to digest must also be slow release (after all it must take far longer for the body to extract the energy from it) and we also assume that if it’s in us longer then it leaves us feeling fuller for longer. This makes sense until we start to understand that ‘feeling full’ doesn’t always mean ‘not feeling hungry’ or ‘not wanting to eat food’. Indeed eating the wrong food can leave you feeling bloated and hungry at the same time.
This is why fasting has such well documented health benefits. There have been numerous studies on the effects of fasting and there is a clear between fasting and improved immunity, reduced inflammation, reduced cancer incident, reduction in diabetes, reduced heart disease and increased energy levels. There are lots of ways people practice fasting, from methods that require you to eat very little for one or two days a week, to systems that require periods each day consuming nothing, to methods that require you to only eat fruit and / or vegetables for certain periods. The reason that fasting is so beneficial is that digestion is an onerous process and giving your body a break gives it some time to recuperate and also, most importantly, to sleep properly.
We tend to think that eating gives us energy, and it does, but only if we are eating the right food in the right amounts. If you are eating food that is difficult to digest, and eating too much of it, you are going to find your energy levels are constantly low due to the energy being diverted indigestion and the disturbed sleep. This type of food is primarily digested at night when it is far more likely to be stored as fat. This is why, although it may seem counterintuitive, cutting back on food and eating lighter food actually leaves you more energetic.
Obviously if you wish to experiment with different types of fasting than you can do so, the purpose of this book is not to provide rules you have to obey, but to explain the basics so you can do what is best for you. The point I wish to make here is not whether to fast or not fast, but merely to explain how and why eating less, and eating lighter, leaves you feeling more energetic and healthier generally. This has an immediate, very positive impact, and long term impact on your day to day life, and greatly outbalances the frustrating and dubious ‘pleasure’ of overeating and poor diet. When we think of eating / not eating we tend of think very simply along the lines of eating being good, and not eating leading to starvation and being bad. We need to stop thinking along these lines. How many people do you know who have starved to death? How many people do you know who are overweight? The diet associated problems we encounter in the Western world aren’t generally deficiencies, but excesses.