Many of us have a love-hate relationship with sugar. We love consuming sweet foods; they taste good and make us happy. But sometimes even a moderate amount puts a dent in our health, triggering reactions like post-sugar bloating, gas, or diarrhea.
Lately, there’s been some buzz that these and other definitely unpleasant flare-ups might be the result of an allergy to sugar. Food allergies are common, but an allergy to sugar—could that explain the crappy way you sometimes feel not long after you have some?
Probably not. “True sugar allergies are extremely rare,” says Cynthia Sass, RD, Healthcontributing nutrition editor. Most people who experience unwanted symptoms after eating sugar, she says, are experiencing a sugar intolerance.
What’s the difference between a food allergy and a food intolerance? “With a food allergy, the body’s immune system, which normally fights infections, sees a food as an invader,” explains Sass. “This leads to an immune response in which chemicals like histamine are released, triggering symptoms such as breathing problems, throat tightness and swelling, hoarseness, coughing, and hives.”
A food intolerance (sometimes called a food sensitivity; they mean the same thing) means that your body can’t digest a food properly, and as a result it irritates your system, adds Sass, typically causing GI distress.
One common type of sugar intolerance is a sensitivity to carbs like fermentable oligosaccharides, disaccharides, monosaccharides, and polyols, which are grouped together and called FODMAPs, says Brooke Alpert, RD, founder of the New York City nutrition practice B Nutritious and author of The Sugar Detox: Lose Weight, Feel Great and Look Years Younger. What makes things even more confusing is that these sugars aren’t just in sweets; they’re in veggies like cabbage, broccoli, and asparagus.
Another kind of sugar intolerance has to do with the natural sugar in milk. “Lactose intolerance is also a type of sugar intolerance,” says Alpert. “It stems from a deficiency of the enzyme lactase, which breaks down the lactose sugar in milk and dairy products when you eat them.” Without lactase, the sugar can’t be digested, and food moves into the colon instead of being processed and absorbed by the gut. Cue the stomach aches, bloating, and gas.
Gastrointestinal issues aren’t the only problems that can crop up if you suffer from a sugar intolerance. In addition to GI distress, you might also experience nausea, headaches, or migraines.
Skin issues are another thing people who are sugar intolerant deal with. Just ask Kristen Bell. Last month, the actress said she cut out sugar after finding that it exacerbated her eczema. Explained Bell on The IMDB Show: “When I eat a bowl of ice cream or something, all night, I call them ‘the sugar shakes’ because all night I wake up and am like trying to metabolize it out or I’m itching and I wake up and am like ‘Oh cool! A really sexy patch of eczema!'”
Everybody is different, of course, so the types of sugars that mess with your body may not be the same as the ones that mess with another person’s system. If you’re sugar intolerant, Alpert says that depending on which enzymes your body lacks, you may have to avoid some foods—but are clear to consume others.
“People with gut disorders like Crohn’s disease and colitis are at risk for adverse reactions to certain sugars, for instance in the form of fructose malabsorption,” says Alpert. These people are often advised to follow a low FODMAP diet or a specific carbohydrate diet to avoid sugars that trigger their symptoms.
How can you determine if you really suffer from sugar intolerance? Meet with a GI specialist or nutritionist, who can pinpoint the specific foods that cause a reaction, as well as help you develop a game plan for nixing them from your plate. Alpert also advises trying an elimination diet—where you remove foods you normally eat from your diet and then reintroduce them, so you can figure out which specific food triggers your symptoms.
“I generally advise my clients to avoid foods that give them any unwanted or uncomfortable physical reactions upon consumption,” says Alpert. “You may be tested for intolerances and told you are clear, but if you feel a reaction or discomfort upon eating a certain food, I advise against consuming it.”