There has been a bit of a brouhaha in the past week regarding the Governments plans to tackle the Obesity bomb that has just begun to explode. I am at a loss for words to begin to explain the stupidity of the planned ‘fat tax’, so I won’t do that here. What I am going to comment on is the equally ‘imbecilic’ advice from Andrew Lansley to ‘Eat Less, Move More’, and the more deserving advice from Jamie Oliver to ‘Eat Differently’.
‘Eat Less, Move More’ has been an oft trotted out phrase by generally good intentioned by woefully ignorant people. This phrase is based on the concept of energy balance, which as I’ve shown has used Calories as a basis for measurement for various reasons, from simplicity to outright fraud. We’ll look at the nutrition side of things here, and possibly return to the physical exercise part in a later piece.
Let’s start with a simple premise:
I can design a program where I can increase your calorific intake by 50% and you will still lose weight (by this I’m referring to bodyfat).
I can also design a diet where I reduce your calorific intake by 50% and cause you to end up fatter.
So in the first case a person can go from eating 2000 Kcal to eating 3000 Kcal per day and actually slim down. In the second case the same person could go from eating 2000 Kcal to eating 1000 Kcal per day and get fatter.
How is this possible when it goes completely against the logic of energy balance? Well it does and it doesn’t. You have to remember that food is not just a container for energy, but is also a chemical signal. These chemical signals can have profound effects on the way the body functions.
Let’s use two isocaloric diets (same amount of Calories in each) of 2000Kcal as an example to explain how this works. This amount of Kcal’s is, according to the authority, the amount required for a 10st 7lb (147lb/ 67Kg) female. Let’s assume she has a fairly reasonable level of bodyfat of 18%.
In the first diet let’s use the Government recommendations for macronutrients (Carbohydrate, Protein and Fat) which are 50:15:35, providing 250g of Carbohydrate, 75g of Protein and 78g of fat.
In the second diet let’s change the ratios to 33:30:37, providing 165g Carbohydrate, 150g of protein and 82g of fat.
According to the Calorie based energy balance argument both diets should maintain weight in the female example. However, what you’ll find is the second diet will cause a reduction in weight, even though the second diet is slightly higher in fat and the total Calories haven’t changed. This is due to the ‘Thermic Effect of Food’ (TEF). Simply put, to digest and metabolise food requires energy, and some foods require more than others.
By increasing Protein and decreasing Carbohydrate, we have to increase metabolism in order to process the nutrient. The TEF can account for 5-15% of your daily energy output depending on what you eat. 15% of a 2000 Kcal diet is 300 Kcal or 2,100 Kcal extra expended per week, without having to raise a pinky.
The above could account for a fat loss of about 1/2lb per week simply by altering your ratios. However, it doesn’t stop there, as Jamie Oliver alluded to; choosing the right food is more important than simply the Calorie content, let’s briefly explore this part.
Food doesn’t just provide energy; it also influences many processes in the body, including hormones. As anyone who has taken the contraceptive pill or a course of corticosteroids will attest, hormones can very quickly affect your level of bodyfat.
I’ve shown previously that depending on your selection of carbohydrates, your body will respond in either a favourable manner or go completely in the opposite direction. In very simply terms, choosing lower Glycemic Index carbohydrates over Higher Glycemic Index will maintain low and stable insulin levels, both which support fat loss and maintenance of muscle. Higher glycemic carbohydrates (except at very specific times) will do the opposite and influence the body to create bodyfat and actually decrease muscle, by taking insulin too high and causing a see-saw effect in levels.
So even if you were using an undesirable macronutrient ratio, you can create an environment for fat gain or fat loss simply by selecting the right carbohydrate.
I won’t go into protein as this can get quite complicated, and I was at risk of boring you 758 words ago, so without tempting fate and hoping you’re still with me, let’s finish up with fats. This section also goes part way to explaining why a ‘Fat Tax’ is ridiculously myopic.
Fats are a perennial target when nutrition is discussed, usually for the wrong reasons. Choosing the right fats will make or break a body. Period.
Current recommendations are to increase monounsaturated and polyunsaturated fats and to reduce saturated fats. Great advice on the surface, but again it’s not this simple. Leaving out monounsaturated fats as they are, not completely, but relatively benign, we’ll locate our gaze on the other two main classes.
For close to 2-3 decades polyunsaturated fats have been promoted as the hero in the fat world, and for good reason. Both Omega 3 and 6 are essential to the body as we cannot make these fats internally as we can with many others. Being essential they have profound effects on the way the body functions, such as, but in no way limited to, levels of haemoglobin and Insulin metabolism, and this is starting to show in the health of the population.
Omega 6 is fairly easy to get in the diet, and the promotion of grain based foods as a basis for a healthy diet has made this even more the case. Omega 3 is not found so readily and even when it is found it spoils very easily, so getting enough in the diet is a lot harder.
This imbalance and its effect on the physiology of the body is one of the reasons for the continuing levels of, amongst many others, Cardio-vascular disease, Cancer and the alarming levels of obesity we are witnessing. If you’ve been reading my work, you’ll have seen the current theory that chronic inflammation is intrinsically linked not only to the above diseases but very much a central player in the ability to control body fat.
What about saturated fats, the much hated, demonised child of the fat family. Even here, it’s not that simple. There are many saturated fats, which all have different effects on the body. Stearic acid, the major saturated fatty acid found in beef, doesn’t raise LDL cholesterol like other saturated fats, but it does promote creation of bodyfat. Other saturated fats such as Lauric acid found in Coconuts do not raise bodyfat. It also raises HDL cholesterol, but also raises LDL cholesterol. So it’s not as easy as saying all saturated fats are bad, as they can have beneficial effects, of which most people are unaware. So the inclusion of saturated fat in the diet is not only warranted it’s actually desirable.
So where does that leave us? Well, if we took Andrew Lansley’s advice and simply ate less, we’d in all likelihood end up both fatter and in much poorer health. If we take Jamie Oliver’s advice to eat differently and more knowledgably, we’d have a vastly healthier nation, and this would be reflected by our sleek physiques.
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