This week we are continuing our talk on sugar substitutes. In our last post we delved into the realm of non-nutritive sweeteners (sweeteners that do not provide calories or other nutrients) and looked at their safety and common uses. This week we move on to the nutritive sweeteners. This group of sweeteners does provide calories and sometimes other nutrients (vitamins and minerals) but are seen by some as healthier alternatives to regular table sugar.
The nutritive sweeteners can be broken down into 3 groups – sugar alcohols, novel sweeteners and natural sweeteners. So let’s dive in!
This name is a little misleading because sugar alcohols do not actually contain any alcohol. They are naturally occurring in some fruits and vegetables, but when used in the food industry they are typically manufactured from a sugar molecule. While they are not considered “non-nutritive” they do provide fewer calories than regular sugar (regular sugar provides 4 Calories/gram, sugar alcohols provide approximately 2 Calories/gram) . Sugar alcohols are often found in sugar-free or no-added sugar candies, cough syrups and other liquid medications. Unlike the super-sweet non-nutritive sweeteners we discussed last time, sugar alcohols are often not as sweet as regular sugar so they are often paired with non-nutritive sweeteners in food manufacturing. In addition to adding sweetness to food sugar alcohols also add bulk and texture.
Sugar alcohols are not are not completely absorbed by our bodies so while they can still cause a rise in blood sugar it is much lower than the blood sugar rise seen with regular sugar. This makes them an attractive sugar substitute for people with diabetes.
Sugar alcohols show up on food labels often under the names of: sorbitol, mannitol, or polydextrose among others.
While sugar alcohols have been deemed safe they can have a laxative effect and cause intestinal discomfort (like bloating, gas, and diarrhea) if consumed in large doses. Typically these side effects are seen when one consumes 50g of sugar alcohols or more, but side effects have even been reported in amounts as low as 10g.
This is a more confusing category as novel sweeteners are a “combination of various types of sweetener” (Mayo Clinic, 2010). Included in this category are: stevia, fructo-oligosaccharide, tagatose and trehalose. These sweeteners come from natural sources but are also manufactured, therefore they can’t be included in the “natural sweeteners” category.
Stevia is certainly the most popular sweetener in this category. Made from the leaves of the South American Stevia rebaudiana plant, the leaves contains steviol glycosides, which give it its sweet taste. Compared to table sugar, stevia extract can be 200-300 time sweeter, so only a very small amount is needed to sweeten food. In fact since such a small amount is required to sweeten food Stevia does not provide calories. Because it does not provide calories Stevia is promoted as being a good option for people with diabetes.
How Stevia is used and regulated depends on how it is manufactured. If the leaf has not undergone purification, the resulting product is considered a food ingredient and not a novel sweetener. These types of Stevia leaf products can be sold for household use as a table top sweetener in Canada but are not approved for use in food products.
Purified stevia extract, on the other hand, is considered a novel sweetener and is regulated as a food additive in Canada. Purified stevia extract is approved to be used in many foods sold in Canada such as certain cereals, yogurts and some drinks.
These sweeteners are gaining more traction as “healthier” sugars and include plant-derived sweeteners like agave, and common sweeteners like honey and maple syrup. These sweeteners are becoming more popular largely because they are harvested as plants as opposed to being created in a lab like many non-nutritive sweeteners or requiring extensive processing like table sugar. However, it is important to note that even the natural sweeteners still undergo processing and refining.
One of the natural sweeteners that is gaining a great deal of popularity is agave nectar.
Agave plants are found in arid, southern places such as Mexico, South America and the southern United States. The center of the plants has syrupy nectar, similar to maple syrup, which has been used for its sweetness by the Aztec people for centuries. Agave syrup is 1.5 to 2 times sweeter than table sugar, which means you can use less of it to get the same level of sweetness. While agave nectar is seen as a more natural alternative to table sugar, it actually undergoes an extensive refining process similar to high fructose corn syrup. Agave nectar contains about 60 calories per tablespoon and provides a small amount of magnesium, calcium and potassium.
Honey has been used since ancient times, but notably for medicinal purposes and not solely for sweetening food. In ancient Egypt, honey was used for wound healing and for embalming. These days, honey is getting a lot of press for its purported health benefits. Scientific studies have discovered more to honey than simply carbohydrate (sugar), but have found many types contain small amounts of vitamins, minerals and polyphenolic compounds (a type of antioxidant). Holistic practitioners extol the virtues of honey and they aren’t technically wrong, however, there is more to it than simply being “good for your health”.
A 2008 review study found that many health benefits of honey would only be present if “consumed at higher doses of 50 to 80 g per intake”. That’s a LOT of honey! Here’s what we know: a tablespoon of honey contains slightly more calories and grams of sugar than a comparable amount of white sugar (64 Calories, 17 grams sugar, to be exact). Honey is used by our bodies in the same way it uses white granulated sugar. Many of the health benefits won’t be seen when consumed in typical amounts. (A little side note: well established evidence exists indicating that honey should NOT be given to infants under the age of 12 months due to a significant risk for botulism.)
Maple syrup: All good Canadians know that maple syrup can be a wonderful way to jazz up pancakes and waffles (and we’re kind of proud of our many maple trees who provide the basis for this delectable treat). Maple syrup, compared with other sweeteners like honey, brown sugar and agave, is an excellent source of the mineral manganese & riboflavin (vitamin B2) (who knew?!). It is lower in calories than honey and is a good source of zinc. But again, like other sugars, it is a concentrated source of calories and should be consumed in moderation.
The world of sweeteners, whether artificial or natural, is a big one. Here we’ve reviewed a some of the most common nutritive sweeteners used in Canada, but if you have questions about natural sweeteners or other sweeteners, post a comment and we’ll do some digging for you.
In our next post we’ll answer the big question around sugar substitutes — do they cause weight loss, weight gain, or neither?
Have a health claim you’d like investigated? Post a comment for us and we’ll add it to the next post.
Until next time, stay sweet!
-Samantha and Sarah
Academy of Nutrition and Dietetics. (2013). Use of Nutritive and Nonnutritive Sweeteners.
Alvarez-Suarez, JM., Tulipani, S., Romandini, S., Bertoli, E., Battino, M. (2010). Contribution of honey in nutrition and human health: a review. Mediterranean Journal of Nutrition and Metabolism. 3(1): 15-23.
Canadian Maple Syrup. (2014). Maple Syrup Nutrition.
Dietitians of Canada. (2013). Sweet Advice on Sugar Substitutes.
Dietitians of Canada. (2014). Nutrition Month 2014 Myths.
Health Canada. (2010). Sugar Substitutes.
Mayo Clinic. (2014). Artificial sweeteners and other sugar substitutes.
The Sugar Association. (N.D.). Novel Sweeteners.