Sweet tasting foods are rare in nature. Fruits and vegetables have some sweetness to them, but they’re also packed with lots of fiber, water, micronutrients and phytochemicals, and are nutritious and quite filling. Honey was hard to find for most of human history and even harder to harvest—it’s protected by an army of stinging warriors.

It’s only in our modern times that concentrated sweetness—in the form of table sugar—grew abundant, and with the invention of high-fructose corn syrup (made from subsidized corn) it became dirt cheap.

Who doesn’t love sweet tasting food? I’ll readily confess—I love chocolate and wish it was on the bottom, roomy part of the food pyramid.

Our preference for sweetness is most likely innate. Food marketers understood its seductive lure, so they started adding sugars to many foods and replaced plain water and milk with sweet drinks. And the consumption of refined sugar skyrocketed. Sweet foods sell!

Alas, too much sugar is a major factor underlying our obesity crisis. It can undermine normal satiety levels, motivating us to eat more than we need while stimulating food cravings. Too much sugar may also raise blood pressure and can elevate blood triglycerides levels (a risk factor for heart disease).

And although sugar is added to many foods—breakfast cereals, condiments and desserts are a few examples—soft drinks and other sugar-sweetened beverages are the primary source of added sugars in Americans’ diets. Soft drinks and fruit drinks combined make up almost half of an average American’s added sugar, and Americans take in about 300 calories from added sugar a day from sugary drinks alone. No other foods or beverages have been associated as clearly with weight gain and obesity as soft drinks.

To our alleged rescue came artificial, non-caloric sweeteners, offering the same intense sweetness without the caloric price tag. There are several such products in the market, all FDA approved: Aspartame (NutraSweet, Equal), Sucralose (Splenda), Saccharin (Sweet'N Low) Acesulfame K (Sweet One) and Neotame.

Are artificial sweeteners a tool in fighting obesity?

Recently David Ludwig of Harvard and Children’s Hospital of Boston and one of America's foremost obesity experts published a commentary in the Journal of the American Medical Association titled: Artificially Sweetened Beverages, Cause for Concern. In this thoughtful commentary, Dr. Ludwig contemplates the potential downsides of replacing sugary drinks with the artificial stuff. Here are some of his main points:

On the up side:

• Short-term clinical trials show that artificial-sweetened beverages may produce short-term weight loss when they replace sugary drinks.

• Artificial sweeteners have been in use for a century, and although there are recurring questions about cancer risk related to their use, no such link has been found.

However:

• There are very few long-term studies looking at what artificially sweetened beverages do to weight, and since body weight regulation is super complex, it very well may be that over time the calories saved by moving to artificial sweeteners are replaced by other foods; in other words, diet drinks may not assist with weight loss. The two long-term studies cited in the paper, which should be interpreted cautiously, surprisingly showed a dose response correlation between consuming diet drinks and the development of obesity, and a correlation between the consumption of diet drinks and the metabolic syndrome and type 2 diabetes.

• Artificially sweetened beverages habituate (or essentially train) our taste receptors to prefer intense sweetness, leading us to reject less-sweet foods (such as veggies and fruit) and “infantilizing” our taste buds to seek sweetness rather than to “grow up” and seek more complex flavors.

• Diet drinks dissociate between the signal and the outcome: Sweetness signifies to our body that energy and nutritious food are on the way, enacting hormonal and neurobehavioral pathways, yet with diet drinks no calories are actually consumed. The outcome of this disconnect isn’t yet clear, but it’s a concern.

• The popularity of artificially sweetened beverages is rising rapidly, and we’re ingesting very large amounts of these synthetic chemicals that are a relatively new addition to the human diet in what Dr. Ludwig calls “a massive, uncontrolled, and inadvertent public health experiment.”

Dr. Ludwig’s conclusion:

"Ultimately, high-quality, long-term clinical trials comparing all three beverage types are needed: sugar sweetened, artificially sweetened and unsweetened. Even if diet drinks produce long-term weight loss when substituted for sugar-sweetened beverages, they might cause weight gain when consumed instead of unsweetened drinks. For now, diet drinks may best be considered an aid in transitioning from high-calorie beverages to traditional, minimally sweetened beverages like water, mineral waters, teas, and coffee with no more than one gram of sugar per ounce (i.e., two teaspoons per eight-ounce cup).”

A perspective by two other eminent nutrition experts, Richard Mattes and Barry Popkin, in the American Journal of Clinical Nutrition came to similar conclusions, saying that: “There are long-standing and recent concerns that inclusion of NNS (nonnutritive sweeteners i.e. non-caloric sweeteners) in the diet promotes energy intake and contributes to obesity.”

Dr. Ayala

Full disclosure: I’m vice president of product development for Herbal Water, where we make organic herb-infused waters that have zero calories and no sugar or artificial ingredients. I’m also a pediatrician and have been promoting good nutrition and healthy lifestyle for many years.

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