At this point, it's common knowledge that too much sugar bad for us. In fact, some doctors even think we should regulate them like we do alcohol. But given all the marketing hype behind different "natural" alternatives, it's hard to know which sweeteners really are the best. Complicating matters, studies—including one published in 2010 in the journal Cancer Research—are finding that fructose, a sugar found in high-fructose corn syrup, agave, honey, and, in much tinier amounts, even in fruit, actually feeds some cancers. That's no reason to give up on fruit or even honey, but when you're in need of a sweetener, make sure you know the difference between the good guys and the bad. And use them in moderation: "Sweeteners should, first and foremost, always be thought of as treats," says Joy Manning, nutrition editor at Prevention magazine.
Bad Guy #1: Aspartame
There's conflicting evidence regarding the safety of aspartame, a common chemical sweetener used in diet soda and other low-cal foods, but some people report headaches or generally feeling unwell after ingesting anything containing the chemical. To make life easier for everyone, this is one instance where you may want to follow the "better safe than sorry" principle. That's because a University of Liverpool test-tube study found that when mixed with a common food color ingredient, aspartame actually became toxic to brain cells.
Aspartame is used in many diet sodas, and researchers are finding that drinking two diet sodas a day can lead to a 500 percent greater increase in waist size. Furthermore, animal studies suggest that aspartame
actually increases blood glucose levels similarly to sugar, which could explain the association between diet soda and diabetes. A final insult: Researchers have found that one harmful breakdown product is formaldehyde, a known cancer-causer. Sweet? We don't think so.
Read More: 9 Disturbing Side Effects of Soda
Bad Guy #2: Agave Nectar
While your health food store likely stocks agave sweeteners, it may be best to keep them out of your cart. Many agave nectars consist of 70 to 90 percent fructose—that's more than what's found in high-fructose corn syrup! "Agave nectar is probably one of the worst sweeteners on the market, and it's deceptive because it's been marketed as a healthy alternative," says nutritionist and author Jonny Bowden, PhD, CNS. "Everybody thinks it's a health food."
Even though it doesn't cause a big blood sugar spike the way regular table sugar does, agave's high fructose levels go directly to the liver, where the organ repackages it as blood fats called triglycerides, increasing heart disease risk.
These high fructose levels can also contribute to insulin resistance, a risk factor for diabetes, as well as nonalcoholic fatty liver disease. "The liver is fat-metabolizer central; it gets rid of toxins," says Bowden. "When there's a lot of fructose coming in, it tends to build up fat deposits around the liver. Everything gets blocked up—it's like the non-EasyPass lane at the tollbooth."
Still, Bowden notes that it's not all or nothing. Using a teaspoon of agave nectar here or there in dessert recipes is reasonable, but you want to avoid drinks and foods sweetened with it.
Read More: 10 Foods That Can Wreck Your Mood
Bad Guy #3: Sucralose
Sucralose, better known by its brand name, Splenda, but sold under other generic labels as well, may originate with sugar, but the end product is anything but natural. It's processed using chlorine, and researchers are finding that the artificial sweetener is passing through our bodies and winding up in wastewater treatment plants, where it can't be broken down. Tests in Norway and Sweden found sucralose in surface water released downstream from treatment discharge sites. Scientists worry it could change organisms' feeding habits and interfere with photosynthesis, putting the entire food chain at risk.
Bad Guy #4: Sugar
Sugar is made up of 50 percent glucose, the component that spikes blood sugar, and 50 percent fructose, the stuff that goes straight for the liver. It's the sheer quantity we're eating that's driving obesity and other diseases. About 100 years ago, humans ate the equivalent of one tablespoon of sugar a day; now it's up to 7 tablespoons daily because sugar is hidden in everything from juices and cereals to bread and condiments.
If your main use for sugar is to sweeten your coffee, Manning suggests experimenting with different coffee brands and roasts until you find one you like black. "There are so many roasts and beans that have different intensities of flavor," she
says. "To my mind, putting sugar in coffee is like putting sugar in a glass of wine."
However, if it's absolutely necessary, a few drops of honey create a surprisingly nice cup of coffee. On those rare occasions that you do use sugar, choose organic to avoid pesticide residues and to ensure the sugar was grown without the use of genetically engineered crops. And choose less processed sugars, like rapadura or turbinado. Although these aren't "healthy," sugars closer to their natural state are likely to be richer in minerals.
Read More: 10 Tactics for Overcoming Sugar Addiction
Bad Guy #5: High-Fructose Corn Syrup
Waistlines have been growing ever since high-fructose corn syrup, or HFCS, sneaked onto the food scene around 30 years ago. With a slightly higher fructose level than sugar, HFCS does most of its damage because it's added to an array of processed foods, including breads, yogurts, ketchup, and even salad dressing. Today, Americans ingest at least 200 calories of HFCS daily. (It's banned for use in organic food.)
According to Robert Lustig, MD, professor of pediatrics at the University of California–San Francisco, HFCS is preferentially stored as fat in the liver and makes people resistant to leptin (a
hormone), which actually increases appetite. A 2009 study published in the journal Environmental Health also found that HFCS is sometimes laced with mercury, a heavy metal linked to autism and heart disease.
Read More: The 5 Best Sweeteners to Have in Your Kitchen