Diet and Fitness Explained

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.

28 Comments

  1. I found this sample chapter of your next book really interesting. I think this will be my next project for myself when your book is out. I read your alcohol explained book when I gave up drinking 15 month ago and found it really helpful. I love the logical way you write. It really works for me. Looking forward to the release of your book. Thank you for sharing your knowledge!

    Reply

    1. Thank you! I was worried about this. Just like when I wrote Alcohol Explained I wasn’t sure if it would be of use to anyone. But at least with Alcohol Explained if no one liked it it could just sink quietly amongst the 2 million other books an Amazon. This time though if it doesn’t go down well it might detract from Alcohol Explained. So far at least the response is good!

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  2. I found this sample chapter of your next book really interesting. I think this will be my next project for myself when your book is out. I read your alcohol explained book when I gave up drinking 15 month ago and found it really helpful. I love the logical way you write. It really works for me. Looking forward to the release of your book. Thank you for sharing your knowledge!

    Reply

  3. Another great post William, thank you. Your Alcohol Explained book was central to me giving up alcohol a few months ago and I have never felt better.
    I love the way you write, concise, fresh, vital insights that are easy to understand. I am really looking forward to the positive change I know this new book will bring -excited is not an exaggeration!

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  4. I enjoyed this sample of the book very much, and am already looking forward to it being published. I also love the way you write: logical, simple to understand, informative and engaging.

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  5. this is brilliant, William. I LOVE your writing style and ..well..it does what it says on the tin… you explain everything so clearly… thank you. can’t wait

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    1. Thank you, I’m setting up a Facebook group ‘Diet and Fitness Explained’ for the new book. I thought I’d keep it separate from the Alcohol Explained site.

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  6. Yes it does seem to be written in the same concise, detailed yet simple language that made you earlier book such a joy.

    The only criticism I had on your earlier book was the failure to explain why lots of people I know seem to be able to drink now and again, then often not for weeks and then again on occasions drink a lot, all without becoming dependent in any way ?

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    1. That is because it takes time to link the relief from alcohol withdrawal to drinking more alcohol, but when you make the link on both a conscious and subconscious level you will always then want to take another drink when you start suffering from the alcohol withdrawal. And when I say alcohol withdrawal I don’t just means the more noticeable effects the day after a big drink, but also the more minor feeling that starts to set in a few minutes after your last drink. Also those who have been drinking more heavily for longer will have brains far more efficient at releasing the stimultents that counter the depressive effects of the alcohol, so this immediate withdrawal will set in more quickly and be more pronounced even during the actual drinking session. When the heavy drinker takes a drink the withdrawal sets in within a few minutes of finishing it, and they know, on a subconscious and often conscious level that another drink will relieve this. The lighter drinker will firstly have a less extreme withdrawal, but in any event won’t link the relieving of this to having another drink. They will feel slightly uptight but simply won’t think of taking a drink to relieve it, so the craving process won’t kick in.

      Hope this makes sense!

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      1. well yes, I suppose I can understand that to a degree but still don’t understand why everyone isn’t ‘hooked’ on alcohol after imbibing ?

        For instance my partner can enjoy a large Baileys and ice say once every 3 or 4 weeks and some times. at similar intervals, when we go out for dinner with friends, she can drink 3/4 glasses of wine but then the rest of the time she isn’t interested and indeed says she prefers chocolate to alcohol ?

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        1. It’s not heroin. You don’t get hooked after one drink. They’re not getting hooked because they’re not drinking enough. What he’s telling you is you have to drink a lot for a long period of time to get hooked. Capisce?

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          1. Yes Mary is absolutely right. To be addicted you need two things. You need a pronounced physiological reaction, and you need to relate, on a subconscious and possibly conscious level, the relieving of the withdrawal with more drinking. Both of these take time, even years of drinking. Reread the Chapter on the process for the binge drinker. It’s in there I think.

  7. Once again, brilliant, Mr. Porter and thank you! Your book alcohol explained has put the nail in the coffin of my drinking. Now, the eating close to bedtime, though I see these hints and tips on the screen at my gym, never really paid too much attention. But, yes, when you know the science the energy it tales to digest is disturbing restful sleep. So, as of today, my main meal will be in the early afternoon! My exercising and fitness have been restored in these last few months and I am keen for even more well being. Looking forward to your new book! Many thanks again!

    Reply

    1. Thank you, hopefully you will find the rest of the book just as useful. dont Forget to join the Diet and Fitness Explained Facebook group either.

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  8. First I want to thank you for writing Alcohol Explained. If I had to recommend one book to someone wanting to quit drinking it would be this book. While reading I kept thinking how much better my life would have been if this was required reading in HS. It really should be! It’s that good!
    You have ruined the joy of drinking for me and for that I will be eternally grateful.
    I’m beyond excited for this new book . I’m an audible girl but I don’t think I can wait that long to listen so I will have to read it in may because I won’t be able to wait til august. Please let me know the minute it is available for purchase, thank you.

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    1. I was a bit disappointed too about the audio version but the mechanics were such that it can’t be ready at the same time. I’d have to delay the kindle / paperback version if I wanted them released all at the same time, which seemed a bit pointless. But I will do what I can to get it ready as soon as possible.

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  9. Thank you. I look forward to being part of the diet and fitness fb group, too.
    Do you have a fb group for alcohol explained?

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  10. That’s very funny -‘ You have ruined the joy of drinking for me’. You have done the same for me, and I feel like I owe you a tremendous amount. I recommend your book as much as I can, especially on the 5:2 Fasting blog. Nearly everybody I know has some kind of issue with alcohol, but (like I was), they are frightened of stopping. But once you’ve stopped, you look back at the wasted years and wish you’d never had a drink. Hey ho. I’ve started living again. I can’t thank you enough.

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  11. I forgot to say – re fasting. Did you look at Jason Fung and his data on insulin resistance, and the importance of letting your body’s insulin levels drop? I guess you did.

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    1. I have a chapter on sugar and insulin. The beauty of publishing on Amazon is that it is very easy to amend, the only time it becomes difficult to amend is after the audio version is recorded. The month or two between the kindle / hard copy being available and the audio version being started will mean I can update and amend. So if you think I’ve missed anything, or parts aren’t clear or you think other bits should be covered. Just let me know. If enough people raise something I’ll cover it off.

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  12. Thank you! I so appreciate this post and your Alcohol Explained freed me from Alcohol. I am 6 months sober and do like AA for the support, but tell a lot of people about your book as this freed me from shame.
    I have been struggling with sugar and seeing that I eat now when I am really anxious. I am practicing meditation, but still really have cravings to put something in my mouth to calm me down. I am trying to watch my feelings, but would love to understand more about why I crave sugar in response to stress. Thank you for what you do as you are changing the culture

    Reply

    1. I do cover this off in my new book. Hopefully you will find it useful. And thank you for recommending Alcohol Explained.

      Reply

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