It’s hard to imagine now, but there was a time when humans only had access to sugar for a few months a year when fruit was in season. Some 80,000 years ago, hunter-gatherers ate fruit sporadically and infrequently, since they were competing with birds.
Now, our sugar hits come all year round, often with less nutritional value and far more easily – by simply opening a soft drink or cereal box. It doesn’t take an expert to see that our modern sugar intake is less healthy than it was in our foraging days. Today, sugar has become public health enemy number one: governments are taxing it, schools and hospitals are removing it from vending machines and experts are advising that we remove it completely from our diets.
But so far, scientists have had a difficult time proving how it affects our health, independent of a diet too high in calories. A review of research conducted over the last five years summarised that a diet of more than 150g of fructose per day reduces insulin sensitivity – and therefore increases the risk of developing health problems like high blood pressure and cholesterol levels. But the researchers also concluded that this occurs most often when high sugar intake is combined with excess calories, and that the effects on health are "more likely" due to sugar intake increasing the chance of excess calories, not the impact of sugar alone.
Meanwhile, there is also a growing argument that demonising a single food is dangerous – and causes confusion that risks us cutting out vital foods.
Sugar, otherwise known as ‘added sugar’, includes table sugar, sweeteners, honey and fruit juices, and is extracted, refined and added to food and drink to improve taste.