You may have seen a recent article appear in several national newspapers regarding doctors calling for a sugar tax to prevent type 2 diabetes.
Of course with any national press you have to read the article with a small amount of scepticism. Usually you find once you start reading the article it doesn’t have anything to do with the headline.
However, it is exactly this kind of headline that confuses my patients and why I thought I’d blog about it today.
Sugar doesn’t cause diabetes
The logical assumption is eating too much sugar causes type 2 diabetes. Many bloggers and ‘so called nutritionists’ will even tell you too much sugar wears out your pancreas – the organ responsible for controlling blood glucose levels.
The theory is your pancreas needs to release large amounts of insulin when sugar is eaten. Over time too much sugar begins to wear down your pancreas because it is over stimulated and eventually causes type 2 diabetes.
This just isn’t the case.
Sugar is just one form of carbohydrate. Other forms of carbohydrate include starchy carbohydrates, fruit, milk sugars and carbs found in beans, pulses and lentils. Quite a variety of food. All of these carbohydrates are turned into sugar or glucose once eaten. Although granted they will be absorbed at different speeds depending on the type of carbohydrate but a healthy pancreas is able to cope with this regardless.
A healthy pancreas will release the correct amount of insulin every time to directly match the amount of glucose entering the system. For more information on what causes type 2 diabetes read here.
So what does cause type 2 diabetes?
Carrying too much fat, genetics and age cause type 2 diabetes. Sometimes a combination of these factors can be the cause. Not all overweight people get type 2 diabetes and there are slim people diagnosed with the condition.
However, 90% of diagnosis are weight related and therefore modifiable with lifestyle changes.
In a healthy body the pancreas releases insulin as we have already mentioned. Insulin acts like a messenger and its message is simple; let glucose in. Insulin acts like a key and it opens the locks to the cells doors to allow glucose in.
The liver also plays a big part in diabetes control. Normally the liver keeps a steady stream of glucose dripping into the blood to keep energy levels up. This is turned off when the liver senses insulin. In other words, insulin tells the liver to stop releasing glucose and instead, start storing glucose and converting it into glycogen.
In type 2 diabetes, the pancreas, body cells and liver essentially are coated in a layer of fat creating shells around them. This can happen because of carrying too much weight, genetics or age. Insulin therefore has difficulty getting out of the pancreas and into the cells and liver due to this shell.
Returning to our lock and key analogy, the locks become clogged up with fat so the keys don’t fit anymore. This means less insulin can get to the cells and liver. It also means the insulin which does get to the cells and liver can’t work as efficiently due to the fat getting in its way.
The consequence of this is not enough glucose gets into the cells and the liver releases glucose unchallenged into the system. As a result, blood glucose levels start to go up and if left untreated, may cross over into a diabetes diagnosis.
Sugar isn’t entirely innocent
Although sugar doesn’t directly cause type 2 diabetes, I wouldn’t say it can have a clear conscience. Eating lots of high sugar foods can lead to gaining weight and such foods tend to be low in nutritional quality.
Sugar is also addictive. It activates the reward centre in the brain. This is the same reward centre that lights up when exposed to cocaine. In other words, when we eat sugar we usually want more.
Have you ever cut out sugar for a period of time and noticed how you no longer crave it after a while. Then once you relapse it’s all you can think about. This reward centre is why.
Therefore, a sugar tax might not be the worst idea in the world if it helps people reduce their sugar intake. Admittedly I’m not usually a fan of such big brother tactics and think people should be able to choose for themselves. However, we do know sugar is addictive and very tasty. So when it’s readily available at cheap prices it’s no wonder people struggle to say no.
I notice it in myself. If cake is going around the office it takes a lot of will power to say no thank you. In fairness, I rarely say no and instead a cake frenzy usually ensues.
Is a sugar tax a good idea?
In order to tackle the type 2 diabetes problem we need people to take control of their own health. Usually this requires a motivator to spark change or a deterrent to abstain from unhealthy behaviours.
Perhaps the sugar tax could be one step in the right direction as cost could act as a deterrent. BUT remember sugar does not cause type 2 diabetes. It can be enjoyed in moderation with no ill effects.
There are many healthy people who eat sugar. There are also lots of people who are unhealthy and have type 2 diabetes who never touch sugar.
It is more about integrating healthy behaviours into your lifestyle focusing on good quality nutrition and regular exercise. This gives you the best chance of a long and healthy life. Therefore, I’m unsure if a sugar tax will help as much as some people think it will. Perhaps more attention should be paid to supporting patients and/or preventative action in the first place.