Fat Causes Fat?

Fat causes fat?

These days it doesn't take much energy to live. Most people own cars - no need to run to catch a bus. And with in-home entertainment centres why struggle to a football match?

At the same time as our energy output has gone down our energy input has gone up. Food is now cheaper than it has ever been. The average UK family spends less than 10% of its income on food. It’s probably fair to say that most people now can afford to eat whatever they want whenever they want it.

Fat intake goes down obesity goes upSo it should come as no surprise that as a nation we are becoming fatter. And it's not a gradual effect. We are getting fatter at an alarming rate. The figure shows the percentage of the UK population classed as clinically obese has increased from 7% to over 23% in the last 20 years. This is probably the fastest change of any measured human parameter in history. Of course, lack of exercise has a major role to play, but so to has diet.

Government and their nutritionists have not been unaware of this alarming trend and in order to stem the tide have exhorted the population to eat less fat. Weight-for-weight fat packs twice the calories of carbohydrates or protein. And indeed the percentage of our energy intake in the form of fat has, in fact, fallen over the past 20 years. But the drop in fat consumption has done nothing to stop the rise in obesity. The current demonization of fat may in fact be ill-advised. The truth is that there are good fats which we need and bad fats which we should avoid. For more info consult Udo Erasmus.

So if fat intake is not the cause of the obesity crisis what is? We must look elsewhere for an explanation. Many scientists, working at the forefront of human nutrition, now believe that the answer lies in the effect that carbohydrates have on your blood sugar level. This is called the glycemic effect..

Low Carbs or Good Carbs? - Questions Answered

How does a GL diet compare with a Low Carb diet?

They are, in fact, very similar. The aim is the same - to keep your blood sugar level stable. But using GL to control blood sugar, rather than carbohydrate restriction, is a safer, more scientific approach than that advocated by many low carb diets.

There is no doubt that low carb diets work. The millions who have lost weight that way will attest to that. But most respectable nutritionists reject the ideas of Dr Atkins as to how the diet works. No one has been able to show that calories from carbohydrates act differently to calories from any other source. Weight gain or loss is still a question of calories in versus calories out.

The current scientific view is that stable blood sugar level depresses the appetite and you simply eat less. This is good news for dieters because it means that you can get the same weight loss effect with low GL diets as you do with low carb diets. The difference being that you are able to eat a great deal more foods, because you can eat good carbs, than you would with low carb diets.

Is the GL rating the same as the Net Effective Carbs?

Both the GL rating and the Net Effective Carb count on a food product are measured in grams. But the GL rating is arrived at by measuring the effect that a food has on blood sugar level whereas Net Effective Carbs are calculated from the ingredients. You can show mathematically that the Net Effective Carb count is an attempt to calculate the GL of a food product. The problem is that it is a crude approximation, which divides carbohydrates into everything or nothing categories and takes no account of the interaction between different food components.

Recently, to overcome this sort of criticism, Atkins Nutritionals has introduced a blood sugar measurement just like glycemic load to categorise their products. It's called The Net Atkins Count and is based on comparing their products to the glycemic effect of white bread. Since white bread has a GI of 70 you can convert Net Atkins Count to GL by multiplying by 0.7. So, for example, a product with a Net Atkins Count of 3g will have a GL of 2g. This is a welcome move by the Atkins Organization which will benefit millions of low carb dieters by introducing them to the concept of glycemic load.

The Glycemic Effect

How does a GL diet compare with a Low Carb diet?

Glycemia is the presence of glucose in the blood and the glycemic effect describes what happens to our blood glucose levels when we eat. (You'll also see the spellings glycaemia and glycaemic, but they look a little archaic if encountered outside a medical journal. So we're sticking with e rather than ae on this site)..

Glucose, C6H12O6 is the primary fuel for all life forms. Whether animal, vegetable or bacteria, all living things use glucose to transport energy around their bodies. Plants pack the energy of sunlight into glucose molecules which they photo-synthesise from water and carbon dioxide. Then, by chaining glucose molecules together they make energy stores in the form of more complex sugars and starches. This results in the food group we know as carbohydrates that are all essentially comprised of glucose building blocks.

Just like plants, we use glucose dissolved in our blood to transport energy around our bodies, in particular to power our brain. When we are not eating, our blood glucose level is remarkably constant, a bit like body temperature. The pancreas is the organ which regulates blood glucose, secreting the hormone insulin if the level is too high, which sends excess glucose to the liver where it is stored as glycogen. If the glucose level is too low the pancreas releases the hormone glucagon which has the opposite effect and converts glycogen back into glucose. Diabetes results when this system isn't working properly [There's an excellent howstuffworks site for more details].

When we eat fats or protein there is very little effect on the blood glucose level. But when we eat carbohydrates there is a very different response. The figure shows the glycemic effect on a normal healthy individual of eating 50g of glucose. (This is by definition a glycemic load of 50g). The dotted line shows the steady fasting level (in this case about 5.4 mmol/L). Eating this load of pure glucose (about equal to a Mars bar and a large Coke), gives a pretty hefty kick to the system. The glucose you eat rapidly ends up in the blood stream almost doubling the normal level. This secrets a large dose of insulin which starts removing glucose from the blood stream and storing it as glycogen in the liver for future use. In nearly all individuals the fall in glucose is as fast as its rise with the result that it ends up below its normal level.The normal body response to this condition is to send out all the signals saying "eat". So most people do, and if they grab a typical sugary snack, the whole process will be repeated.

So the very act of eating high glycemic food is to trigger the desire to eat more. Many nutritionists are now coming round to the view that continually eating in this high glycemic manner is a major cause of not only obesity but its associated diseases of diabetes and heart failure. For further reading on this there is a good review, with lots of references, on the Linus Pauling Institute website.

Natural Eating

How does a GL diet compare with a Low Carb diet?

With all the conflicting advice as to what you should or should not be eating in order to stay healthy, it would be nice if there was some guiding principle we could use to help us through the maze. One idea which we think is valid and very useful is the concept of "Natural Eating". Natural Eating is all about asking the question "What are humans naturally adapted to eat?" And since changes to our physiology only occur on evolutionary timescales of millions of years, we need to think back to human diet before the invention even of agriculture.

Anthropologists can tell us quite a lot about what our ancestors ate. Our closest relative, the chimpanzee is largely vegetarian, but not at all averse to taking the occasional termite or tree squirrel. Most anthropologists now agree that the development of hunting and fishing played a major part in human evolution. So a natural diet would be rich in meat, fish, vegetables, whole grains, nuts, seeds, and, for sweetness, fruit and honey. The striking thing about these natural foods, to which our bodies are adapted, is that the all have a zero or relatively low glycemic load.

High glycemic foods seem to be a modern invention. Bread has only been around for a few thousand years and sucrose (table sugar) for only a few hundred! It is interesting that fructose, which is the primary sugar of honey and many fruits has a very low glycemic effect. We at the GoodCarb Food Company use fructose (sparingly) as our sweetener of choice. Unlike other carbohydrates, fructose does not breakdown to glucose in the body but behaves more like a fat, going straight to lipids. This fact, together with the increasing use of high fructose corn syrup (HFCS) in the USA , has led to a number of writings, some scientific, some sensational, suggesting that the obesity epidemic in the USA has been caused by fructose. It may well be that the American addiction to sugary drinks has a major role to play in the obesity crisis but it also may well be that it isn't the fructose in HFCS that's the villain. You see, HFCS isn't particularly high in fructose, it amounts to only 55%. The remaining 45% is glucose and other highly glycemic saccharides . Maybe it's the 45% that isn't fructose that leads to obesity?

We try to stay well away from such modern inventions at The GoodCarb Food Company! In particular, we won't use any non natural ingredients such as artificial sweeteners in our products. We follow the Natural Eating principle.