To Eat, or Not to Eat (Artificial) Sweets?


For decades, artificial sweeteners offered the promise of delivering the sweet fix consumers crave, but with zero calories and zero effect on blood sugar. As a result, they have become one of the most widely used food additives in the world. Food companies have progressively added artificial sweeteners to all sorts of foods and beverages, from Greek yogurt to sodas and even salad dressings, with the appealing allure of weight loss and diabetes prevention.

But new research calls into question whether these very products that promised to help could be doing more harm than good. Scientists have zeroed in on a surprising way that artificial sweeteners may actually accelerate the development of glucose intolerance and metabolic disease through altering our microbiome, the colony of friendly bacteria in our gut that actively plays a role in shaping our health.

The Microbiome/Metabolic Health Connection

Scientists found that consuming artificial sweeteners can actually spur glucose intolerance by altering the makeup and functioning of the microbiome. In mice, consuming artificial sweeteners lead to higher blood glucose levels after 11 weeks compared to mice who consumed water, or even sugar water. Researchers mapped some startling changes to the mice’s microbiome after consuming artificial sweeteners, including a shift in their gut bacteria population that favored obesity and diabetes.

But what about humans, researchers wanted to know? Here the microbiome was also modified. In humans, four out of seven study volunteers without any prior history of using artificial sweeteners showed early signs of developing glucose intolerance within just one week of adding them to their diet. And here’s the microbiome/metabolism connection: those who had poorer glycemic response after consuming the artificial sweeteners for a week also underwent changes to their microbiome, while those with no metabolic changes showed no change in their microbe gut profile. 

What to Do Now

This groundbreaking study may shed light on one of the questions that has long perplexed researchers and health experts, which is why Americans have continued to get heavier despite decades of widespread use of artificial sweeteners. It also helps to pinpoint exactly how the products we eat and drink actively shape our microbiome in a surprisingly brief amount of time. 

The bottom line is that while artificial sweeteners may have zero calories, mounting evidence suggests they still have metabolic consequences. Until we know more, it’s best to avoid them rather than seeing them as a silver-bullet solution for sweet taste without any calories.  If you do choose to consume sweets, and don’t currently have insulin resistance or type-2 diabetes (in which, case talk to your doctor before adding any additional carbohydrates to your diet) indulging in small amounts real sugars may be best. But the key is to keep it small. The American Heart Association recommends no more than 10% of total calories come from added sugars over the course of a day in all the foods and beverages you consume. That’s about six teaspoons (100 calories) for the average woman, and nine teaspoons (150 calories) for the average man. And remember, an optimal diet for deep metabolic health should be based in minimally processed whole foods, plenty of vegetables and fruits, nuts, fish, beans and lean meat and poultry, whole grains and no sugar sweetened beverages.