It seems we cannot go more than a decade or two before the world of nutrition is turned on its head and everything we previously held to be good and healthy is demonised as the cause of all our weight loss woes. And so it goes for carbohydrates... once the pillar of nutritional health, carbohydrates now find themselves under attack.

The accusations are wide-ranging and complex. Let's take a look at the crimes of which carbs are accused:

  • Carbohydrates are the cause of obesity because they stimulate insulin which, in turn, causes fat storage.
  • Carbohydrates can reduce the body's sensitivity to insulin, increasing the chances of becoming diabetic.
  • Carbohydrates prevent fat loss because the body will not release fat stores when insulin levels are elevated.
  • Carbohydrates are mostly empty calories and lead to overconsumption which, in turn, results in excess weight gain, obesity and other metabolic syndromes.

These accusations are just the tip of the iceberg, but constitute perhaps the most commonly held beliefs regarding carbohydrates and, to be fair, each of them does have some validity.

CRIME 1: Carbohydrates are the cause of obesity because they stimulate insulin which, in turn, causes fat storage.

Carbohydrates do indeed stimulate insulin, and insulin can cause the body to store calories consumed in fat cells as triglycerides, especially refined carbohydrates which are low in fibre and can be rapidly broken down into sugar.

However, in healthy people eating a healthy diet, including high fibre, unrefined carbohydrates, insulin levels cycle quite naturally and do not appear to contribute to excess fat storage, so long as the total calories consumed do not exceed total daily energy expenditure.

CRIME 2: Carbohydrates can reduce the body's sensitivity to insulin, increasing the chances of becoming diabetic.

It is true that excessive carbohydrate consumption can play a role in reducing insulin sensitivity, but we now know that the causes of diabetes are multifaceted and far too complex to be explained by carbohydrate consumption alone.

Individual genetics, activity levels, poor sleep and body fat levels all have their own role to play in diabetes, and recent science suggests that it would be naive to lay the blame solely on the influence of carbohydrates.

CRIME 3: Carbohydrates prevent fat loss because the body will not release fat stores when insulin levels are elevated.

Blood sugar levels rise when we eat, and fall as insulin enters the bloodstream and stores those sugars into fat cells or muscle tissue. While this process is going on, the body will not release fat back into the bloodstream for fat burning, and so, in that sense, carbohydrates do prevent fat burning but these cycles are perfectly natural, and when wholefood carbohydrates are consumed as part of a healthy diet, there is no cause for concern.

In fact, by stimulating insulin release, carbohydrates also stimulate the release of another hormone, leptin, and leptin is responsible for controlling satiety levels. Without the release of leptin, we would be more inclined to consume excess calories which, in turn, would lead to increased fat storage.

CRIME 4: Carbohydrates are mostly empty calories and lead to overconsumption which, in turn, results in excess weight gain, obesity and other metabolic syndromes.

This final accusation highlights the real issue with the confusion surrounding carbohydrates. A big part of the problem is that people tend to get quite confused in their understanding of what carbohydrates actually are. Many of the accusations do hold true when considering refined carbohydrates such as flour-based products and highly processed foods. Especially when consumed by people who are either already in poor health, diabetic, inactive or who have other conditions which can be exacerbated by eating high calorie, low nutrient, low fibre, sugary foods.

However, we should not forget that the food industry did not invent carbohydrates, and before there were supermarkets, carbohydrates were readily available in the form of vegetables, fruits, pulses and all manner of nutrient dense, high-fibre, energy-packed foods.

It has been shown that consuming refined, processed carbohydrates will make us prone to eating more food, more often, which of course contributes heavily to excess weight gain, obesity and various metabolic issues. But, just try to overeat on carrots, broccoli, lentils or apples, it's nigh-on-impossible.

And therein lies the crux of the defence against carbohydrates. Cutting out carbohydrates, especially the processed, refined kind, can be beneficial if you are trying to lose weight or body fat, as it helps you to eat fewer total calories. It may also potentially play an important role in managing or reversing diabetes and other metabolic issues. However, for healthy, active people, eating a healthy diet; real, wholefood carbohydrates, packed with nutrients and high in fibre, help us to stay healthy, happy and full, so let's not throw out the baby with the bathwater, again.