The Health Risks of Sugar

Q: Is it true that sugar is more dangerous to our health than salt or fat?

A:  Dr. Zachary Levine: A recent article published in Nature was entitled “The Toxic Truth About Sugar.” In it, the authors make the case that one of the most dangerous substances for our health is sugar and, worst of all, high-fructose corn syrup (HFCS), also known as glucose/fructose in Canada. HFCS is made from corn syrup that has been broken down to change some of its glucose to fructose, which is twice as sweet as glucose. As people have decreased their fat and salt consumption, many are inadvertently consuming more sugar to increase flavour, and the North American food industry uses HFCS as a cost-effective sweetener.

Sucrose comes from sugarcane and sugar beets and is our table sugar. It consists of glucose and fructose. Fructose is of concern because it is broken down only by the liver and can lead to fat deposition in the liver. Fructose metabolism results in increased uric acid and triglyceride levels, which is a form of bad cholesterol. The current evidence indicates that sugar – and especially HFCS – may be as unhealthy as fat and salt and may be associated with the metabolic syndrome of obesity, diabetes, high blood pressure and high cholesterol as well as the aforementioned fatty liver.

But that doesn’t mean you should avoid all sources of sugar. Fruit, for example, is a natural source of sugar and, more importantly, fibre, which fills us up more quickly, slowing our body’s rate of sugar absorption.

While all carbohydrates are broken down into sugar (glucose), which we use for energy, refined carbs have been stripped of some of their natural health components, such as fibre. It is also known that less refined carbohydrates are healthier than more refined ones, which is why brown bread and pasta is recommended over white bread and pasta.

As with everything, moderation is key. “A little is not a problem,” says study author Dr. Robert H. Lustig, “but a lot kills – slowly.” Check product labels and remember to remain physically active, which regulates blood sugar levels and helps maintain a healthy weight.


Dr. Zachary Levine is an attending physician in the department of emergency medicine at the McGill University Health Centre in Montreal.