Sweet Sugar Science

Scrolling through whole-food and “paleo” dessert recipes, I disappointingly find processed sweeteners within the ingredients list. Clarifying the “refined-sugar free” concept with a food blogger recently, I realized that the terms “processed sugars” and “refined sugars” carry alternate meanings among online communities. To set the record straight, I’ll clarify some sweet sugar basics.

 What is a sugar?

 A “sugar” is a processed and refined powder or liquid sweetener that contains roughly 50% fructose, fruit sugar, and 50% glucose, your body’s source of fuel. In addition to sucrose (table sugar), sugar is a sweet chameleon with now over 60 different names including maple syrup, honey, agave syrup or nectar, evaporated cane juice, date sugar, coconut palm sugar, fruit juice concentrate, molasses, rice syrup, high-fructose corn syrup, beet sugar, any ingredient ending in “ose” like maltose or dextrose, and many other sneaky terms.

Fruit sugar (fructose) and carbohydrate sugar (glucose) are metabolized differently in the body. Because fructose is metabolized primarily by the liver and bypasses the glucose negative feedback loop, a diet high in processed sweeteners may distort appetite, encourage abdominal weight gain, increase the risk for developing insulin resistance and metabolic syndrome, and potentially damage the liver.

Aren’t “natural” sugars unprocessed?

All store-bought sugars are processed to some extent. For example, maple syrup doesn’t flow from the maple tree in the dense product found in the bottle – evaporation and heating create the concentrated syrup. Even raw honey must be extracted and separated for use. Evaporated cane juice is not derived from juice at all, but rather from cane syrup.

If you use bananas or dates as natural alternatives to commercially-processed sweeteners, you need to manually “process” the fruit to create a usable paste. Processing breaks down the fiber, causing the product to be quickly absorbed in the body, unlike whole fruit.

Are “natural” sugars unrefined?

The term “refined” means that a food has been modified to remove impurities or unwanted substances. All packaged or bottled sugars have been refined, so none of them meet the definition of “refined-sugar free.”

Isn’t a lower glycemic-index sugar like agave syrup healthier?

The lower glycemic load found in agave syrup is measured from its glucose content, which is very low. However, agave syrup contains one of the highest amounts of fructose compared with other sweeteners, roughly 80-90% fructose, which makes this sweetener less desirable than table sugar. Even high-fructose corn syrup contains only 55% fructose.

If fructose is considered unhealthy in large amounts, then what about fruit?

As stated by researcher and author Dr. Robert Lustig, fructose without fiber is problematic. For most of us, we can benefit from eating whole fruit in its unmodified form.

What about fruit juice?

Commercially-produced juice is the same as liquid sugar, similar to soda, and should rarely be consumed.

Which sugar should I use for baking or sweetening foods?

Because most sugars are biochemically similar to table sugar, the choice really depends on desired consistency and individual preference. It’s important to understand that sugars should be limited to occasional treats, with an emphasis on those sweeteners that provide added nutritional value.

There isn’t a magical sugar with no negative attributes when consumed in excess. Sugars are hidden in most packaged products, including yogurt, granola bars, and condiments, so we’re consuming sugar more frequently than we realize.

I personally choose a fruit sweetener like bananas or dates rather than a sugar sweetener whenever possible. However, even these fiber- and nutrient-rich fruits can leave a heavy fructose load. As a result, balance is key, and use of sweeteners in moderation is the best advice.

What about no-calorie sweeteners like stevia?

Although there’s no caloric impact from non-nutritive sweeteners such as aspartame, sucralose, or stevia, these processed “diet” additives do not offer a consequence-free indulgence.  There’s a strong link between no-calorie sweeteners and weight gain. Non-nutritive sweeteners may alter gut microbiota and gut hormones, possibly increasing appetite and the expectation for a sweet fix.  

Stevia is processed from the leaves of the Stevia rebaudiana plant using ethanol (alcohol), while store-bought stevia may contain sugars like dextrose or other sugar alcohols. Like other commercial sweeteners, stevia isn’t particularly “natural.” As with other sugars, discretion and moderation are recommended.

Author: Laura Farnsworth, MS, CNS, CN, Integrative & Functional Nutritionist at Craving4Health.com

References

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