Sugar is a pretty sweet business: our evolution designed us to love it as the easy-to-use energy molecules that glucose,fructose, and sucrose are, so it should be no surprise that global sugar consumption rates have been rising non-stop for about half a century. What is surprising is how fast this growth has been, how it has changed our lifestyle and medical landscape, and whether or not our bodies can differentiate between different sugars or the same sugar from different sources.

1. You eat a lot more sugar than your ancestors, and more than your parents, but increases have started to level-out.

There are lots of different types of sugars (or carbohydrates, which are sweet due to their extra OH groups), but we will focus primarily on fructose and glucose. Intake of fructose per day, alone, rose 18% between 1970 and 2004. Although we consume more sugar per day, per person, we have not seen the increase of 46% more sugar, per day, per person that the BBC and others are claiming. According to a review by Wittekind et al, 2014, per person per day sugar intake has started to stabilize and maybe even decrease.

Here is actual data about fructose intake, per day, from Duffey and Popkin, 2009:


2. We almost all consume more sugar than is healthy/advisable


A single serving of carbohydrates contains 15 grams of carbohydrates. Different carbohydrates influence your blood sugar at different rates (for instance, sucrose/saccharose will be slightly more slow than glucose or fructose, since these are what results from hydrolizing sucrose). After looking at the infographic above, I know I certainly don’t fit into the limit of 6 tablespoons of sugar prescribed by the WHO per day.

We once primarily ate sugars that naturally occurred in fruit and vegetables, but science implied that added sugar is now the primarily source of sugar in our diets. The problem with adding sugar is that it is not bound up with other nutrients, such as fibre, making it harder for our body to keep track of full you are. The WHO uses the term ‘free sugars’ to describe free-floating sugars that are instantly absorbed by the digestive system. All sugar that is added to our food is classified as ‘free sugars’. A concern with free sugars is that they make it easy to eat excess calories; you may drink a can of soft drink but you would not eat 4 apples in a single sitting because the fibre in the apples makes you feel full. Free sugars are not necessary for a balanced diet.

3. Fructose raises blood sugar slower than glucose, but it isn’t always necessarily “better”.

Studies have repeatedly shown that you see a higher and faster spike in blood sugar after you eat free glucose than if you ate free fructose. This would make it seem that fructose is better, but consuming too much fructose is pretty much just as bad as consuming too much glucose.

Glucose is not metabolized during its first pass through the liver, unlike fructose. This leads to a slower and less dramatic spike in blood sugar. At the same time (according to the same 2009 study linked above), fructose leads to a higher level of triglyceride formation (which is a kind of storage fat). Which is better? Well, it depends on what you are trying to avoid.

4. Honey is in some ways better (in the sense you are likely to use less of it), but is also recognized by your body as reducing sugars like glucose, fructose, and saccharose. It is still a free sugar and you should keep track of your consumption.

If you remember, saccharose had a lower direct effect on blood sugar levels than glucose. Still, saccharose is just a fructose and a glucose molecule. For comparison with other disaccharides: maltose is composed of 2 glucose molecules, lactose is composed of a fructose and galactose molecule, making honey (containing glucose, fructose, and saccharose/sucrose) likely better than malt.



When I say “better,” I mean slightly less likely to lead to an overdose of sugar. Keep in mind that glucose can be turned directly into glycogen (a form of energy storage) and is allowed through the liver initially to be used directly as energy in the peripheral tissue. Fructose has to first be processed by the liver, which may carry the cost of overtaxing the liver.

Overconsumption of any of these free sugars can lead to insulin resistance, which can lead to diabetes. The WHO prescribes not letting sugars represent more than 10% of your daily calories (they recommend 5%, but say 10% is the definitive line), but  it is estimated that the ingestion of sucrose, HFCS, and other sugars accounts for ∼25% of energy consumption in the United States.

5. Foods containing more than ~10% sugar (so 10g sugar in 100g of food) are considered high in sugar. Look at the label, if you care.

An apple contains about 12g sugar per 100g, making it a good reference point for sugar content. Try not to eat things that contain a greater sugar content than apples, and if you do, try to compensate with low-sugar foods so as to not use sugar for more than 10% of your calories.


6. Free sugars can carry lots of names, and I haven’t mentioned them all.

If you want to reduce your intake of free sugars, look for the following in the ingredients:

  • Sucrose
  • Glucose
  • Maltose
  • Lactose
  • Fructose
  • Molasses
  • Hydrolysed starch
  • Agave nectar
  • Corn syrup
  • Rice malt syrup
  • Honey
  • Golden syrup

7. Sugar is addictive, and you are able to reduce your dependence only be realising you have one.

Researching to write about this text, I realized I’m a sugar addict. I consume foods regularly that contain high sugar levels, from my breakfast cereal to my marmalade and honey. When friends make pancakes or cake, there is sometimes up to 30% sugar in them!

Sugar, specifically glucose, seems to lead to increase dopaminergic (neurons that use dopamine) activity. Our body sees glucose as a reward, since sugar is a high-energy quick-release currency for your body (it seems to induce ATP production, which is the basic form of energy in your body along with NADH) that makes it easy for cells to get the energy they need. Evolution has conditioned your body to reward the discovery of sugar, and you have to consciously work to avoid manipulation by food and drink companies.