Sugar - why can it be so bad for us?

I doubt there are very many people in this country that haven't heard about sugar being bad for our health. In fact, not very long ago, on April 6th, a new tax on soft drinks containing added sugar has come into effect here in the UK with the aim to reduce obesity rates. Many leading brands have reduced the sugar content of their drinks as a result, but quite a few, including Coca Cola, have not. It's likely that many people will simply end up paying more for their drinks rather than reducing their sugar intake.  

But why is sugar just so bad for our health?


Humans evolved on a diet very low in sugar and with no processed carbohydrates, such as our staple white bread or pasta.  If you think about it, a thousand years ago people would have had very few treats of honey or fruit even, and yet these days we are often so accustomed to the taste of sugar that vegetables, such as broccoli or cauliflower, seem just bland or bitter.
Sugar is, in fact, still relatively new in the Western World. It was first brought in from India where sugar canes were grown and then squeezed to produce a sweet liquid that was then turned into sugar crystals. In Europe, it was at first considered a spice or medicine and was expensive to buy. In the 18th century, however, it was commonly used in even the poorest of families to sweeten coffee and tea or to make jam. Hello jam sandwiches! (Extremely high in sugar!) In the 19th and 20th centuries different types of sugar and sweeteners have then been developed, such as high fructose corn syrup (much cheaper than sugar) and these are now difficult to avoid in ready-made meals or other processed foods, such as cakes and biscuits. 

Everybody knows that sugar is bad for our teeth. But it is also hugely responsible for the high rates of diabetes we are seeing in the Western World. In the UK, more people than ever have diabetes- about 3.9 million of which 90% have Type 2 diabetes. Probably far more shocking, though, is that 1 in 3 adults in the UK are estimated to have prediabetes, the condition that precedes diabetes.(Ref1) 

What's diabetes again?

There are two main types: type 1 and type 2. Both affect the way your body regulates blood sugar, also called glucose. This sugar comes from the foods you are eating (the carbohydrates in your diet) and is then used in the many, many cells in your body to create energy. But glucose cannot reach your cells on its own: it needs insulin to take it there! No insulin, no energy- it's pretty important!
Now if you've got type 1 diabetes, your body simply doesn't produce insulin. Type 2 diabetes, however, is quite different: your body is no longer responding to insulin as well as it should. This is called insulin resistance and you can end up with chronically high levels of sugar in the blood- and as a result high levels of insulin, too. 

And if you've got raised insulin levels, you've not only got a much higher risk of developing type 2 diabetes, but it can affect you in other ways, too, such as increasing your risk of developing age-related disorders, causing an undesirable change to your blood fats or contributing to high blood pressure. 

But if I can get one message out there then it's this one:

sugar blog entry message.jpg

Let me explain why:
High levels of sugar in your blood can be dangerous and that's why your body is good at taking any excess out. So any surplus glucose that's not needed for immediate energy production gets stored via insulin in the liver and muscles, but if these stores are full then the extra glucose gets converted into fat and is stored as adipose tissue. (Often around the waist!) And as I've said, excess glucose in your blood triggers the release of high levels of insulin. The problem is that these high insulin levels can actually become so high that you end up with too much sugar being taken out of your bloodstream. Result? You can feel tired and grouchy. The sugar crash- who hasn't experienced it?
Not so nice, however, if you feel like this most of the day, every day....

How to reduce sugar spike

Sugar comes from carbohydrates, but different carbohydrates have varying effects on our blood sugar depending on how quickly they get broken down into glucose.
Examples of carbohydrates that can rapidly raise our blood sugar levels are:

  • starchy vegetables, such as potato and swede
  • sugary breakfast cereals and cereal bars
  • sugar and many other sweeteners, such as honey or maple syrup
  • ketchup and other sauces
  • many ready-made meals have high levels of sugar in them: check the label!
  • white bread, white pasta, white rice 
  • cakes and biscuits, chocolate and sweets
  • juices and soft drinks
  • canned fruit
  • ice cream and many fruit yoghurts

Examples of carbohydrates that have a slower effect on our glucose levels include:       

  • whole grains, such as millet, quinoa, barley
  • non-starchy vegetables, such as cabbage, broccoli, cauliflower, leeks, tomatoes, cucumbers, salad, kale, chard, spinach, carrot, fennel...many!
  • brown bread, brown pasta and brown rice (the fibre present in these slows down the breakdown into glucose)
  • fruits high in fibre, such as apples (unpeeled), berries and pears 

Ideally, carbohydrates that quickly raise your blood sugar are best avoided and considered a treat. But even the latter type with the slower effect eventually break down into glucose. To avoid peaks and troughs of blood sugar levels (and the unwelcome symptoms that those can lead to) we need balanced meals: a balance of protein, fats and carbohydrates at every meal. Why? Because protein and fat take longer to digest in the gut, and this then slows down how quickly the sugar from your carbohydrates get released into your bloodstream. 

I will be writing more about the importance of protein and good fats in our diet at a later point. But for now I'd like to challenge you:

See if you can identify where most of your sugar consumption might be coming from and then try to give up those foods/drinks for three days. How does it make you feel?