Horizon on fat: a mechanism is not a cause

Last night, BBC2’s Horizon programme discussed “new” discoveries about what lies behind the “obesity epidemic” that’s assailing us. It was a fascinating programme, and did indeed reveal some very interesting things: but fascinating as it was, it was also deeply misleading.

It was presented by a surgeon who began, so the programme told us, with the belief that obesity was a consequence of people eating too much, and exercising too little. People who exhibited such behaviour did so because they were too weak-willed to do any better. Ergo, what was required was some stern talking, possibly the compulsory viewing of “Supersize vs Super-skinny” (well, had it not been on a rival channel), and for those whose wills were not thus strengthened, the reluctant intervention of an already over-stretched NHS to deal with their inevitable type 2 diabetes, and perhaps an opportunity to recoup some of the money by selling voyeuristic clips of yet another stomach by-pass operation in action. The latter probably wouldn’t be very effective, as the market for gruesome shots of implements that “cut and staple simultaneously” would seem already to be saturated. Every time yet another programme turns the spotlight on our modern gross fatness, and what we might do about it, it seems it is de rigueur to include surgeons at this most unattractive pastime.

But the surgeon starring in yesterday’s programme was obliged to confess to an unsavoury attempt to “take the moral high ground” with her simplistic view that perhaps obese people might have some slight degree of responsibility for their predicament. Because she was wrong. It was all down to genetics. Fat people have a “hunger hormone” that is frankly too lazy to make them feel really hungry when its owner is really hungry, and instead merely makes the hapless person feel a bit peckish all the time. On the other hand, obese people have a “fullness hormone” that never gets its act together at all, and never informs the brain that enough is enough. Later in the programme it was revealed just how the brain was responding to all this hormonal misinformation: thin people’s brains were hardly exercised at all by pictures of cream doughnuts, whilst fat people’s brains produced a veritable frenzy of irresistible urges that their rubbish fullness hormone utterly failed to control.

So obese people are between a rock and a hard place. It is truly wrong to hold them responsible. On the one hand their hormonal chemistry is all up the creek, and on the other their brains conspire against their every attempt at self control. The answer? Well, it seemed to be either hormonal pills, or else an odd side effect from the ubiquitous stomach by-pass surgery referred to earlier, which seemed to have the unlikely additional benefit of re-educating the brain.

It was easy to be carried away with the programme’s scientifically certified approach. Except for one rather glaringly obvious point that was never mentioned at all. The human brain has been as it is for a rather long time. The body’s hormonal chemistry has been as it is for millennia. And yet the obesity crisis that we are constantly being told about has only really taken off in the last, say, 50 years. It’s only reached the consciousness of TV producers in the last 20. Thus I can with absolute confidence say that the cause of this crisis is not to be found in endocrinology or in brain functionality, neither of which has suddenly changed in the last half century. A cause and its effects cannot possibly be separated by such an extravagant slice of time. To believe this proposition is to believe that fundamental aspects of our biology, that never bothered our species before, have suddenly begun to do so. Obviously not.

What the Horizon programme so carefully and thoroughly revealed was not a cause, but a mechanism. The cause is much more obvious, and simpler. It is that our Western diet has changed over the last 50 years in very deleterious, but very profitable, ways. At the same time, our level of physical activity has dropped precipitately. What we can learn from yesterday’s revelations is that this sorry state of affairs does not affect us all equally. Some of us are better equipped than others to resist the doleful consequences of rubbish food and physical slothfulness. True also is the programme’s point that resistance is easier for some of us than others.

What would a rational response be? Surely it would be to attack the causes, rather than to fiddle about with the mechanisms, a fiddling about that is bound to bring other unforeseen consequences in its wake. Why don’t we do this? For two very different, but actually strangely connected reasons. We don’t attack the food culture that is causing our fat malaise because too many people make too much money from its continuance. And we prefer drug or surgical interventions in mechanisms to attacking causes because drugs and scientific medicine are also major money-spinners. Not only that, scientists are as seduced by their flashy toys as any adolescent is by his or her iPad, or Android device, or X-Box console. How much more fun to play with an MRI scanner, or wield a tool that simultaneously cuts and staples, than to wonder about the dominance of hawkers of confectionery or fast food? I can still remember my excitement when I first got to use an electron microscope.

Yes, we should be careful to remember that obese people are indeed people about whom we should care, and not fools that we should castigate. But we should also be very wary of those who would locate every problem in genetics or chemistry, and who seek to minimise human volition or responsibility.

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If you are what you eat, then I’m this…

A lot of people are entirely allergic to any television programme that might be described as “reality TV”. Whilst that is often not a bad rule of thumb, I don’t personally agree with such a sweeping generalisation. One such programme that I find by turns fascinating, morbidly voyeuristic, enlightening and irritating is Channel 4’s “Super-size versus Super-skinny”. For the reality TV allergic amongst you this programme brings together two members of the public that have opposing eating disorders. One is “super-sized”, rolling in folds of fat and eating gargantuan quantities of all the wrong foods. The other is “super-skinny”, addicted to punishing exercise, and lives on a couple of haricot beans and a gallon of sugar-free coke a day with resulting skeletal frame and multiple nutritional deficiencies. Under the watchful supervision of a handsome and perfectly proportioned doctor these two unfortunates are then invited to eat each other’s diets for several weeks. The grossly fat one stares disconsolately at a breakfast of water and single digestive biscuit, whilst the minuscule one tries with greater or lesser gusto to force down a grease-laden repast of 10 eggs, several beefburgers, and a couple of bags of crisps, whilst casting a doleful eye on the mid-morning snack of bacon sandwiches that they will shortly also have to consume.

It is nothing if not shock therapy. As in all the best of the reality genre, there is a liberal oiling of cod-psychology to keep everything slipping along nicely, and if you’re lucky you might get a couple of scenes of bitter recrimination in which the thin one fails to consume all the goodies on offer and is chided by the fat one, who claims that the thin one is not keeping to the bargain. In return, the thin one demands to know how they are expected to consume half their own body weight at every sitting. Interspersed between the sequences of ill-matched meals and psychological warfare are the voyeur shots of anatomically incomprehensible folds of blubber in the one case, and a pitifully protruding skeleton in the other.

One of the programme’s fixtures is a scene in which each participant’s weekly food and drink intake is gathered together in one modest, and one spectacularly vast, pile. The contestants (for that is what they really are) are then obliged to stare in horror and amazement at what they are doing to themselves. The doctor intones in a sympathetic but authoritative voice-over all the evils of obesity, the diabetes, the heart disease, the worn-out joints: and the equal and opposite evils of vitamin and mineral deficiency, of potential heart failure, or of acid reflux that will bedevil the anorexic.

But it’s those piles of weekly food that tend to catch my eye. We don’t normally see our week’s food paraded in front of us. And it’s made me wonder what my pile might look like. I’ve absorbed at some level or another over the years all the healthy eating messages with which we are bombarded at every waking moment, but I’ve never really considered what I actually eat en masse. I have no idea how close or far I am from that magical 5 daily portions of fruits and vegetables; from that average man’s 2,500 calories a day; from the proper quantity of saturated and unsaturated fatty acids.

So I’ve decided to find out. I’m keeping a food diary, but I’m not making any attempt to change or modify my diet. I’m simply noting down as accurately as I can everything I eat or drink (other than water). For meals that I prepare for myself (the vast majority) I’m trying to capture quantities and calorific values, but when I eat outside of my home, then I’m using my best guess as to both ingredients and quantities. I started doing this last Wednesday, so later today I’ll be reporting on the week from then (6th April) to yesterday (12th April). I’m not doing it meal by meal, but instead creating my own virtual weekly pile à la Super-size vs Super-skinny. I’ll keep it up as long as I can, or at least until boredom overtakes me. I recognise that no 2 weeks are identical, and that in order to get a reasonable grasp of what I am if I eat this, I need to average it over several weeks. If I really get into the swing of it, and find I’m able to do it over a longer time frame, well I can always sell the results to some researcher into British eating habits.

Food’s not everything, since there’s expenditure as well as income in the food accounts. I work in an office, and am as perfect a sedentary worker as you could wish to meet. Most days I do little walking, although I do always walk up the stairs to my 6th floor office and eschew the lift. However, to set against this, I am rigorously disciplined in taking exercise every day on my cross-trainer. I have programmed it so that I do the equivalent work of 400 calories every weekday morning (before breakfast if you’re interested) and this equates to between 35 and 45 minutes exercise depending on the heart-rate I’m exercising at. The longer times are when I’m working at 122 beats per minute (about 75% aerobic capacity at my age) whilst the shorter times are when I’m working at 146 beats per minute (about 90% aerobic capacity). In addition therefore to the food and calorie data I’ll be reporting, I’ll also include blood pressure, resting heart-rate, and body weight.

So look out for my first set of results later!! And if you’re a doctor or nutritionist, please feel free to analyse my life-style and tell me if it’s still worth me worrying about my pension!