The Sweet Truth
by Cara Ocampo
At the far counter of the coffee shop, you see the packets of sugar substitutes beckoning. Presumably, the soft tones of their wrappers and “zero calorie” taglines aim to soothe. For many people, however, the pink, blue-and-yellow pastel colored packages might not quiet the question that has been nagging at the back of their mind: what am I actually stirring into my drink?
It is a salient question in an age when diabetes afflicts about 285 million people worldwide and will likely claim an additional 153 million patients within the next 15 years. The strong correlation between the incidence of diabetes and hyperglycemic, hypercaloric diets is enough to make even tepidly health-conscious adults skim the sugar content of their drink before taking a sip.
A new sweetener released earlier this year may soon join the lineup at the coffee counter. Named Dolcia PrimaTM Low-Calorie Sugar (adopted from the Italian words for “sweet” and “first”), it comes from British sugar producer Tate & Lyle PLC. This new sugar substitute is one that the Splenda®-maker hopes will “transform the way the food and beverage industry develops low- or reduced-calorie products.”
What makes this product different from any other sweetener, you ask? It consists of D-allulose, an isomer of fructose and glucose that occurs naturally in a variety of foods, including wheat and Worcestershire sauce. With about 90 percent fewer calories than sugar, Dolcia Prima rivals current sugar substitutes in low caloric content. It is less sweet than other products on the market, as it is only 70 percent as sweet as sugar. Splenda, on the other hand, is hundreds of times sweeter. But Dolcia Prima may have a leg up on the competition with additional benefits of antioxidant properties and hyperglycemic suppression, according to a 2012 study published in the Journal of Agricultural and Food Chemistry. Perhaps, researchers surmise, it could eventually be used for the prevention of diabetes, atherosclerosis and obesity.
The excitement around Dolcia Prima’s potential recalls an old question that its competitors have long faced: are low calorie sweeteners really an improvement over sugar?
Ideally, they are. Overconsumption of cane sugar, or sucrose, increases blood glucose and insulin levels. The increased insulin demand that results can exhaust the pancreatic beta cells that produce insulin. Sweeteners that are not metabolized by the body, on the other hand, such as Dolcia Prima, Equal (aspartame), Splenda (sucralose) and Sweet N’Low (saccharin), are not expected to cause the same jumps in blood glucose and insulin, and are often marketed as safe sugar alternatives for those suffering from and at risk for developing diabetes.
But not everyone is convinced that this is the case.
A research study published last year in Nature suggested that consumption of non-caloric artificial sweeteners could actually increase glucose intolerance in mice by altering their intestinal microbiome. To date, no extensive studies have been performed to establish this trend in humans. Nevertheless, many consumers tend to look askance at artificial sweeteners.
The distrust of sugar substitutes has a long history. From the 1980s until 2000, Congress mandated that all saccharin-sweetened products declare that saccharin “may be hazardous to health,” after a study proposed that saccharin ingestion had induced bladder cancer in rats.
Equally, aspartame has long experienced a bad reputation. A 1996 article published in The Journal of Neuropathy and Experimental Neurology entitled “Increasing Brain Tumor Rates: Is There a Link to Aspartame?” highlighted a rise in brain tumor diagnoses in the years following the introduction of aspartame. Despite limited evidence to the correlation, widespread unease toward aspartame has affected the sweetener’s market performance. Both Pepsi and Coca-Cola have attributed the declining sales of their “diet” soda lines to customer fears regarding the safety of aspartame. In response to such concerns, Pepsi recently replaced the aspartame in its Diet Pepsi formula with sucralose. Interestingly, however, the sales of Coke Zero are increasing, despite the aspartame used to sweeten the beverage.
Attempts to convince the public are a hard sell. New York Times columnist Dr. Aaron Carroll learned this the hard way last July. In his article entitled “The Evidence Supports Artifical Sweeteners Over Sugar,” Caroll noted that, with the exception of those with phenylketonuria, “aspartame isn’t a concern. […] In normal use by most people, all of the approved artificial sweeteners are safe.” Among the dissenting readers was a group of aspartame researchers at Rockefeller University Hospital. They responded by stating that “artificial sweeteners may be no worse than natural sugar, but it has been shown definitively that they are not better, and freely consuming them as a ‘healthy alternative’ poses potential risks.” Another reader pointed out, “We were once led to believe that ‘light’ and ‘low tar’ cigarettes are better choices than regular cigarettes – neither choice is actually healthy. It’s time that we recognized the same thing about sweetened beverages.”
To skeptics’ credit, sugar substitutes do pose some major challenges in spite of conflicting studies regarding their potentially adverse effects. Sucralose, for instance, has raised environmental concerns for its increasing occurrence in and challenging removal from wastewater. Additionally, some sugar-alcohol sweeteners, such as sorbitol and mannitol, can generate uncomfortable laxative effects and bloating when consumed in large amounts. Not to mention, of course, the challenges of finding new substances that can satisfactorily replace the taste of sugar. Grant DuBois, a former Coca-Cola-researcher who is now a sweetener-consultant, points out that apart from sweetness, sugar substitutes must satisfy numerous additional metrics. These include lack of aftertaste, stability in solution, resilience to wide variations in temperature and low manufacturing cost.
Despite the growing push for more “natural” sweeteners, the pool of viable candidates is small. Stevia has emerged as a contender in recent years. Derived from a genus of plants in the sunflower family, it contains steviol glycosides—which are natural non-caloric sweeteners—as well as antioxidants. But the plant-based sweetener has a major downside: when used in sodas, which require high concentrations of sweetener, Stevia does not compare favorably with sugar, producing a bitter aftertaste. And while the bitterness might be minimal in a single teaspoon, it is difficult to ignore in the several teaspoons of sweetener required for beverages like Coke and Pepsi. As a result, Stevia would be inadequate as the sole sweetener of a low-calorie soft drink. It is instead used to reduce sugar in mid-calorie sodas.
So, what if you are looking for the “perfect” sweetener—with just the right quality of sweetness, no calories and a low glycemic index?
It probably does not exist at this point. While researchers are still excited about the potential health benefits of Dolcia Prima, only time will tell whether or not it yields significant improvement over existing sweeteners. Until then, it is a matter of picking your poison.
Or selecting your saccharide, as it were.