The Connection Between Added Sugars and Disease

Without a doubt, high consumption of added sugar has been implicated in nearly every chronic disease, including obesity, cardiovascular disease, diabetes, non-alcoholic fatty liver disease (NAFLD), cognitive decline, and some cancers.

Public health initiatives are becoming increasingly necessary to address the multifactorial nature of added sugar consumption and chronic disease. Yet, complex carbohydrates underpin the healthiest dietary patterns in the world, such as the Mediterranean dietary pattern.

Nutrition education on carbohydrates and added sugars has never been more important.

Added Sugars Come at a Cost to Our Health and Our Wallets

As a country, chronic disease treatment costs Canadians an estimated $190 billion annually, representing 67% of total healthcare costs, with $68 billion attributed to treatment and the rest due to lost productivity. These numbers are expected to rise unless we can design effective individual and public health interventions.

Just this past September, Newfoundland imposed a 20 cent per litre tax on sugar-sweetened beverages, sparking mixed opinions by consumers. Is this a violation of human rights? Could this curb rates of diabetes? What will be done with the revenue generated from this taxation?

This is the first time such a public health measure has been done in Canada, but not the world. National campaigns to reduce added sugar by taxation have occurred in over 45 countries.

Furthermore, pervasive marketing from the food industry influences consumer choices toward foods high in added sugar. There are numerous examples in the breakfast cereal, and sports drink industries. Michael Gregor, Medical Doctor and founder of nutritionfacts.org – a science-based non-profit organization – and author of the book “How Not to Diet” compellingly illustrates the influence of the food and marketing industry on the consumption of processed foods, also typically high in added sugars.

Fad diet trends and social media have also conflated added sugars and carbohydrates together, impacting health behaviours on both a physical and mental health continuum. It is reasonable to consider that inconsistent or misunderstood messaging on carbohydrates could also be related to increased rates of disordered eating, particularly in youth.

Carbohydrates Are Essential For Life

Let’s be clear – carbs are not the enemy. 

C­arbohydrates are the primary energy source for your body. For example, your brain relies almost exclusively on glucose, a form of carbohydrate, for fuel and function. During high-intensity sports, carbohydrates are the body’s primary fuel source for optimal performance.

A simple way to think of carbohydrates as simple or complex. 

Complex carbs are larger, take longer to digest, and help control blood sugars. They are also typically high in fibre, helping with metabolism and digestion. They are typically whole, unprocessed foods that provide many other essential nutrients. We find them in whole foods such as whole grains, legumes, fruits, starchy vegetables, nuts, and seeds.

Simple carbohydrates are smaller molecules, require little digestion, and get absorbed easily into the blood. Added sugars fall into this category. We find them in sugar-sweetened beverages like pop and sports drinks, specialty hot beverages, children’s breakfast cereals, pastries, and condiments. They are added to many o­­ther convenience foods. You can also find simple sugars in healthy foods, like fruits. Still, the overall benefit of the whole food source (i.e., from fibre, vitamins, and minerals) will in most cases, outweigh any negative.

Generally speaking, moderate consumption of complex carbs is associated with low risk of chronic disease, whereas excessive consumption of simple carbs is associated with poor health outcomes.

How To Recognize “Sugar” on Nutrition Ingredient Labels

There are many “hidden” names for added sugar in ingredient lists. Other common names for added sugar on food packaging are dextrose, glucose, lactose, fructose, maltose, invert sugar, cane sugar, brown sugar, raw sugar, malt sugar, malt syrup, corn syrup, agave nectar, high fructose corn syrup, maple syrup, molasses, honey, fruit juice concentrate, cane crystals, evaporated cane juice, and others. 

A good rule of thumb is to limit purchase of foods that have “sugar” in the first 3-4 ingredients.

Interestingly, sugar on the nutrition facts label does not differentiate between natural sugar and added sugar. So, apple sauce, for example, could have added sugar and naturally present simple sugars.

When reading a nutrition label to determine the total absorbable carbohydrate (i.e., carbs that will be converted into blood sugar and used for energy or storage), you must subtract the fibre. Fibre is not absorbed into the blood and does not have a caloric value. This tip is especially important for diabetics who need to count carbs, and also because fibre can help control blood sugar levels.

Is There Evidence For Sugar Addiction?

Ultra-processed, high-sugar foods are also thought to be addictive, but is there proof?

The topic to this day remains debated in the scientific community. Despite interest, there is a surprising lack of good-quality human studies.

What we do know – Consuming sugar releases opioids and dopamine, providing rationale for the addiction hypothesis, but there is a surprisingly low number of quality human studies. 

This question was investigated in animal models in a 2007 review which has since been cited over 1700 times in academic literature. Analyzing three components of addiction (i.e., bingeing, withdrawal, and craving), the authors concluded that under certain circumstances, evidence suggests rats can become sugar-dependent. 

Human studies are more complex, however. And there is still controversy surrounding the definition of sugar “addiction” versus the complex biology of sweet-taste hedonics. A recent review paper as recent as 2016 concluded that sugar addiction should not be recognized in scientific literature or public policy due to a lack of current evidence. 

7 Tips For Decreasing Added Sugar in Your Diet

One final tip is to be conscious of added sugars, moderate your consumption, but not overly restrictive. Overly restrictive eating behaviours are often not sustainable and can have the opposite effect. There are strategies that can help with this process beyond the scope of this article that we can explore together.


Carbohydrates are an essential form of energy, and are ingredients in many of our favourite foods. Added sugars in excess can contribute to chronic disease. There are many factors that influence our consumption of added sugar from food marketing and public health initiatives to neurochemistry and our relationship to food. Either way, reducing added sugars in the diet may be a great goal for your health journey, and both Britney Lentz and myself can help! 

Dan Neuman
Registered Dietitian MSc

Return to Article Library

Book a Consult
  • Schedule
    your complimentary

  • This field is for validation purposes and should be left unchanged.