Fighting Flab

In my last post, I underwent a scientific ramble upon the subject of fat, going into a little of the basic chemistry and biology of the whole business. However, what I did not touch so much on is the giant elephant in the room that surrounds all talk of fat in our modern world, and looks poised to become one of the defining issues of the twenty-first century- that of obesity and overweightness.

I am not, however, about to analyse obesity as a whole in this post, but instead intend to consider why attempting to counteract this, and the slimming industry in general, have become such major bones of contention for so many people. There’s no denying that the slimming industry is worth a veritable fortune- one analyst I saw on TV the other day estimated that a simple cure-all for the world’s obesity problem could be worth up to four trillion dollars, particularly given the boom in public obesity in countries like Brazil and China. However, this doesn’t mean that slimming is popular or that everyone goes in for it- if slimming down weren’t such a problem for so many people, there wouldn’t be an obesity problem worth speaking of, and it’s an open secret that around 99.9% people attempting a new diet fail to keep any weight off in the long term.

To begin, let us consult the very basics. For practical purposes in terms of losing weight, fat is basically energy stored by your body in physical form; the formation of the triglyceride molecules that make up fat requires energy, ‘using up’ any excess energy your body may have, and breaking them apart (the leftover ‘bits’ of the broken-down triglyceride molecules are effectively waste products that are transported to the kidneys via the bloodstream, and are later eliminated from the body in urine) releases this stored energy for your body to use, in order to keep your various bodily functions going and allowing you to move around and do things. Thus, any difference between the amount of energy your body consumes (in food, mainly; a ‘calorie’ is nothing more than an old unit of energy, just like the ‘joule’ unit used in modern science) and uses is offset by your fat reserves- if you put in more than you get out, your fat stores increases, and vice-versa. Thus, the only real challenge facing a slimmer wanting to shed their excess fat is to expend more energy than they consume (leaving to one side for this post various claims that certain foods make you fatter than equivalents of a similar calorific value). Just so we’re all clear on this.

The first concern to raise its ugly head when considering this problem is the simple question of ‘how much energy do we actually expend per day?’. Many people will look to the little table of government-issued Guideline Daily Amounts of various nutrients that you find on the side of most food packaging, but it must be remembered that these are only ‘Guidelines’ after all and a more personal evaluation may be of use. The amount of energy your body uses per day is known as your Metabolic Rate, and a good starting point for an aspiring slimmer would be to calculate your Resting Metabolic Rate (RMR). One’s RMR is a measure of how much energy a person of your gender, age, height and weight would normally (some people may have unusually fast or slow metabolisms, but these people are rare and ‘I have a slow metabolism’ is more often an exuse than reality) expend per day were they utterly at rest; not moving, not doing anything, this is the minimum amount of energy your body needs in order to function. RMR calculators such as this one are freely available online, and that one also features a separate calculator (under ‘Calorie Calculator) that allows you to (very roughly) estimate your total calorie consumption per day. The final number you get out of this latter process is a very useful guideline to the aspiring slimmer.

However, simply aiming to eat less than that number is no guarantee of long-term weight loss. For one thing, many people give up on diets because they can see no immediate results, but this is because ‘burning’ fat is an inherently slow progress. Depending on your source, fat stores between 7500 and 9000 calories per kilogram, meaning that if you are on a diet in which you eat 500 calories less than you expend (and I’m being generous here; a 500 calorie shortfall will leave you feeling very hungry), you can only expect to lose a kilogram of fat every 2-3 weeks. Even this may be  masked if our hypothetical slimmer decides to exercise a bit more too; regular exercise will cause a person to put on muscle (which weighs more than fat) and thus make the loss of weight seem less impressive- but we’ll come onto exercise in a minute.

The other major issue facing those who try to lose weight by dieting is the fact that diets are really, really unpleasant. For one thing, the constant calorie-counting provides unwanted mental strain for many (hence the popularity of points-based diets and similar that do the calculations for you), and this mental fatigue can serve to only exacerbate the gnawing hunger in our empty bellies at the end of a day when we’ve eaten enough calories but not enough to satisfy our stomach. Not only do dieters frequently feel hungry, they also have to deal with a bland diet of lettuce and cottage cheese- and however much we can pretend that we find these delicate things delicious, they don’t quite compare to the stomach-filling satisfaction of a thick, fatty, meaty burger.

The problem is that our hunger is not dictated by how many calories we have consumed, but by how physically full our stomach is, and whilst there are a few tricks that can be used to try and counteract this (a personal favourite is to down a pint of water when feeling peckish, just to give my stomach a large physical amount of stuff to process) none of them really compare to everyone’s dream of being able to eat as much as they like and still not get thin. So, if attempting to limit our intake of energy alone isn’t enough (although diet is most certainly a vital part of keeping our weight down), our only remaining option is to increase the amount of energy we expend, and that means exercise.

The benefits of exercise in relation to weight loss are generally poorly understood by most people; whilst the very act of getting our bodies moving does expend energy, as the little calorie meter on an exercise regime may show, the actual amount of excess energy expended by this process is usually very little; a half-hour run may only expend a cupcake’s worth of energy. No, the real benefits to exercise concern the metabolism; exercise and leading a generally active lifestyle causes your overall metabolic rate to rise, which is why relatively short but regular bouts of exercise (which constantly ‘top up’ one’s metabolic rate) are generally more productive than a four hour long weekend blowout that only boosts the metabolic rate for a small portion of one’s week. This is why the oft-quoted adage instructing people to do 10,000 steps per day has hung around for so long; I honestly believe that were everyone to follow this advice, there would not be a serious obesity problem. Not only that, but as mentioned before exercise, particularly intense exercise such as sprinting or weight training, will build muscle- muscle whose cells will need to be constantly provided with energy in order to stay alive, thus increasing one’s metabolic rate in the long- as well as short-term.

One final pitfall to be noted with attempting to lose weight in this fashion involves attempting to keep it off. It must be borne in mind that people of a lower weight have a lower RMR and thus need less energy, meaning that if a successful dieter reverts to their pre-diet practices they will be eating too much and will just balloon back to the weight they were. Thus, when one makes a commitment to exercise or better eating it has got to be a genuine change in lifestyle (something very few people are willing to commit to) in order to work for the long-term.

That’s one of two reasons why an unpleasant diet of celery sticks probably isn’t a great weight loss solution; the other reason concerns the other benefit of exercise. Someone who regularly exercises isn’t just likely to be slimmer than a similar person who doesn’t, but to be healthier as well- their heart will be healthier, their muscles more able to perform practical real-world tasks, and their body is generally less likely to suffer from the ravages of time and disease. A lot of the stated health problems that come from being overweight or obese are merely symptomatic of people who eat bad food and don’t exercise sufficiently, rather than being directly caused by being overweight. That’s why very few people worry after the cardiovascular health of Jonny Wilkinson, World Cup-winning rugby star and shining light of Toulon RC: a man whose BMI classes him as morbidly obese.

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Why the chubs?

My last post dealt with the thorny issue of obesity, both it’s increasing presence in our everyday lives, and what for me is the underlying reason behind the stats that back up media scare stories concerning ‘the obesity epidemic’- the rise in size of the ‘average’ person over the last few decades. The precise causes of this trend can be put down to a whole host of societal factors within our modern age, but that story is boring as hell and has been repeated countless times by commenters far more adept in this field than me. Instead, today I wish present the case for modern-day obesity as a problem concerning the fundamental biology of a human being.

We, and our dim and distant ancestors of the scaly/furry variety, have spent the last few million years living wild; hunting, fighting and generally acting much like any other evolutionary pathway. Thus, we can learn a lot about our own inbuilt biology and instincts by studying the behaviour of animals currently alive today, and when we do so, several interesting animal eating habits become apparent. As anyone who has tried it as a child can attest (and I speak from personal experience), grass is not good stuff to eat. It’s tough, it takes a lot of chewing and processing (many herbivores have multiple stomachs to make sure they squeeze the maximum nutritional value out of their food), and there really isn’t much of it to power a fully-functional being. As such, grazers on grass and other such tough plant matter (such as leaves) will spend most of their lives doing nothing but guzzle the stuff, trying to get as much as possible through their system. Other animals will favour food with a higher nutritional content, such as fruits, tubers or, in many cases, meat, but these frequently present issues. Fruits are highly seasonal and rarely available in a large enough volume to support a large population, as well as being quite hard to get a lot of down; plants try to ‘design’ fruits so that each visitor takes only a few at a time, so as best to spread their seeds far and wide, and as such there are few animals that can sustain themselves on such a diet.  Other food such as tubers or nuts are hard to get at, needing to be dug up or broken in highly energy-consuming activities, whilst meat has the annoying habit of running away or fighting back whenever you try to get at it. As anyone who watches nature documentaries will attest, most large predators will only eat once every few days (admittedly rather heavily).

The unifying factor of all of this is that food is, in the wild, highly energy- and time-consuming to get hold of and consume, since every source of it guards its prize jealously. Therefore, any animal that wants to survive in this tough world must be near-constantly in pursuit of food simply to fulfil all of its life functions, and this is characterised by being perpetually hungry. Hunger is a body’s way of telling us that we should get more food, and in the wild this constant desire for more is kept in check by the difficulty that getting hold of it entails. Similarly, animal bodies try to assuage this desire by being lazy; if something isn’t necessary, then there’s no point wasting valuable energy going after it (since this will mean spending more time going after food to replace lost energy.)

However, in recent history (and a spectacularly short period of time from evolution’s point of view), one particular species called homo sapiens came up with this great idea called civilisation, which basically entailed the pooling and sharing of skill and resources in order to best benefit everyone as a whole. As an evolutionary success story, this is right up there with developing multicellular body structures in terms of being awesome, and it has enabled us humans to live far more comfortable lives than our ancestors did, with correspondingly far greater access to food. This has proved particularly true over the last two centuries, as technological advances in a more democratic society have improved the everyman’s access to food and comfortable living to a truly astounding degree. Unfortunately (from the point of view of our waistline) the instincts of our bodies haven’t quite caught up to the idea that when we want/need food, we can just get food, without all that inconvenient running around after it to get in the way. Not only that, but a lack of pack hierarchy combined with this increased availability means that we can stock up on food until we have eaten our absolute fill if so we wish; the difference between ‘satiated’ and ‘stuffed’ can work out as well over 1000 calories per meal, and over a long period of time it only takes a little more than we should be having every day to start packing on the pounds. Combine that with our natural predilection to laziness meaning that we don’t naturally think of going out for some exercise as fun purely for its own sake, and the fact that we no longer burn calories chasing our food, or in the muscles we build up from said chasing, and we find ourselves consuming a lot more calories than we really should be.

Not only that, but during this time we have also got into the habit of spending a lot of time worrying over the taste and texture of our food. This means that, unlike our ancestors who were just fine with simply jumping on a squirrel and devouring the thing, we have to go through the whole rigmarole of getting stuff out of the fridge, spending two hours slaving away in a kitchen and attempting to cook something vaguely resembling tasty. This wait is not something out bodies enjoy very much, meaning we often turn to ‘quick fixes’ when in need of food; stuff like bread, pasta or ready meals. Whilst we all know how much crap goes into ready meals (which should, as a rule, never be bought by anyone who cares even in the slightest about their health; salt content of those things is insane) and other such ‘quick fixes’, fewer people are aware of the impact a high intake of whole grains can have on our bodies. Stuff like bread and rice only started being eaten by humans a few thousand years ago, as we discovered the benefits of farming and cooking, and whilst they are undoubtedly a good food source (and are very, very difficult to cut from one’s diet whilst still remaining healthy) our bodies have simply not had enough time, evolutionarily speaking, to get used to them. This means they have a tendency to not make us feel as full as their calorie content should suggest, thus meaning that we eat more than our body in fact needs (if you want to feel full whilst not taking in so many calories, protein is the way to go; meat, fish and dairy are great for this).

This is all rather academic, but what does it mean for you if you want to lose a bit of weight? I am no expert on this, but then again neither are most of the people acting as self-proclaimed nutritionists in the general media, and anyway, I don’t have any better ideas for posts. So, look at my next post for my, admittedly basic, advice for anyone trying to make themselves that little bit healthier, especially if you’re trying to work of a few of the pounds built up over this festive season.