3. Artificial Sweeteners
Hype: In the 1960s, artificial sweeteners found their way into soft drinks and were marketed as a dieter’s dream: all the sweet and none of the sin. Today, saccharin (Sweet’N Low), aspartame (NutraSweet, Equal) and acesulfame-K and sucralose (Splenda) are ubiquitous parts of the American diet. Aspartame alone appears in more than 6,000 products and is gulped down by 54 percent of Americans. Because artificial sweeteners are low in calories and sugar-free, food makers market them to both dieters and people with diabetes (two groups with ever-expanding memberships). The sell is that calorie-free sweeteners are healthier than sugar and less likely to contribute to weight gain or blood-sugar disorders.
Reality: Research has shed light on the possibility that these sugar substitutes may hurt the very people they are purported to help. In a study of more than 3,600 people, published in 2008 in the journal Obesity, researchers at the University of Texas Health Science Center at San Antonio were stunned to discover that people who drank artificially sweetened beverages, such as diet sodas and artificially sweetened tea and coffee, gained 47 percent more weight during a seven- to eight-year follow-up period than people who avoided artificial sweeteners. These findings were based on long-term changes in individuals’ body mass index, or BMI, and all analyses were adjusted for each person’s BMI at the start of the study. Specifically, it found that consuming more than 21 artificially sweetened beverages per week (vs. none) was associated with an almost doubled risk of becoming overweight or obese among the 1,250 individuals who were normal weight at the study’s outset.
So what gives? Although the study didn’t investigate the underlying mechanisms of weight gain, lead investigator Sharon Fowler, MPH, suggests a couple of plausible scenarios: For starters, she says, “The brain is very good at counting calories.” Meaning, it likes to consume the same amount of calories every day. “So, if you switch from Coke to Diet Coke and cut out 400 calories a day from sugar, your body may try to compensate elsewhere.” The upshot is that you may end up eating all the calories you saved, and then some.
Then there’s a dynamic known as “taste distortion.” Artificial sweeteners, made to fit snugly into the mouth’s sweet-taste receptors, are up to 13,000 times sweeter than sugar. Fowler and her colleagues speculate that teasing the taste buds with noncaloric sweeteners may stimulate appetite without providing any of the calories that would produce satiety. Instead, she explains, “they create a craving for intensely sweet, highly caloric food.”
Other research suggests that noncaloric sweeteners may also trigger the body’s cephalic phase response, in which the brain responds to the taste of something sweet by releasing insulin (the body’s normal response to a rise in blood sugar) even though there’s no sugar for the insulin to process. The net result: disrupted blood sugar, sugar and carb cravings, and resultant weight gain.
If you’re svelte, it might take more than a fear of weight gain to pry that Diet Coke from your hand. But Fowler cautions people not to underestimate the other health risks of artificial sweeteners. “These drinks are just a slurry of chemicals, and we’ve not yet begun to understand their total health risks.” She is particularly leery of sucralose and aspartame, pointing to research and consumer experiences that indicate aspartame can trigger responses ranging from skin rashes to migraines — and worse. One possible culprit may be formaldehyde, an indirect metabolite of aspartame. “People who are highly sensitive to formaldehyde may be the canaries in the mineshaft,” she says. “I’m concerned that the long-term effect on other vulnerable individuals may be a slow, neurological toxicity.”
Better choice: First, strive to reduce your intake of sweets and sweetened beverages overall. If you are in the habit of enjoying several sweetened beverages a day (regardless of how they are sweetened), make it a priority to replace them with water or herbal tea.
When you do choose to enjoy a sweetened food or beverage, give preference to sweeteners closest to their natural state, such as honey, maple syrup, agave nectar or raw sugar. But remember, sugar is sugar, and most natural sweeteners digest as quickly as refined sugar — so don’t overdo it.
If an inflammatory disease, such as diabetes, heart disease, cancer or arthritis, has you cutting back on the sweet stuff, but you still crave the occasional treat, agave nectar is probably your best bet. Extracted from cactus sap (the same cactus used to make tequila), agave nectar is three times sweeter than white sugar but its glycemic index is four to five times lower than that of honey. That means it digests more slowly and, therefore, won’t spike blood-sugar levels.
Stevia is another option, but its calorie-free status raises some of the same concerns critics have noted about artificial sweeteners. While small amounts of Stevia (and its processed brand-name counterpart, Truvia) are not likely to pose any health risks, high doses of the herb have caused reproductive problems in rats, so consider it a second choice, and avoid commercial products that rely on Stevia as a sweetening ingredient.
No matter which sweetener you choose, keep in mind that feeding a sweet tooth is simply going to increase your cravings for more sweets and refined carbs and will also reduce your ability to enjoy the natural sweetness of fruits, vegetables and whole grains. So, swap good sweeteners for bad, but use them in moderation.