8 Healthy Foods That Can Still Mess With Your Blood Sugar
Watching your sugar intake? Here's how to keep things balanced.
Keeping blood sugar stable isn’t just about preventing type 2 diabetes. Blood sugar, also known as glucose, is an important energy source for your body. When you don’t have enough (or you have too much) it can cause pesky symptoms like brain fog, mood swings, and junk food cravings, all of which can put a damper on your energy level and productivity.
You might assume that simply steering clear of foods with a high glycemic index (meaning they raise blood sugar levels too quickly) is all it takes to keep your glucose from going haywire—but food-based blood sugar fluctuations are actually completely unique to the individual, says Monica Auslander Moreno, R.D., Florida-based registered dietitian and nutrition consultant for RSP Nutrition. The index is a good jumping off point, but even foods that are lower on the index can cause blood sugar shakeups in certain people.
The smart thing to do is to keep tabs on the foods that make you feel funky, no matter where they fall on the index, and either cut back on those foods or combine them with grub that’s higher in fiber, protein, and healthy fats, which will slow how quickly your body metabolizes them and help level out your glucose.
To get you started, here are eight healthy foods that can often cause blood sugar spikes—and the best ways to balance things out:
While couscous does contain important nutrients, such as protein and selenium, it’s also higher in simple carbohydrates, which metabolize into sugar and spike blood glucose, says Connecticut-based board-certified cardiologist Garth Graham, M.D.
The fix? Pair couscous with foods that can help even the score—a good place to start is to add it to your salads, says Graham, as spinach, kale, and other lettuces are known to lower blood sugar.
People assume that because beets are vegetables, they’re a “free” food that you can consume endlessly, and your blood sugar will remain in a stable zone. Not so, says Moreno.
Starchy vegetables—like beets, carrots, and jicama—contain higher amounts of carbs, and because of this, can raise blood sugar much faster than non-starchy veggies. Moreno recommends limiting starchy veggies to a half cup serving per day and pairing them with foods that contain healthy fats or protein to reduce the glycemic response. For example, enjoy beets with a full-fat plain yogurt onion dip, or consume carrots and jicama with your favorite go-to guac.
Most plant-based milks aren’t a source of protein or fat—they’re typically more carb-based, especially ones that are made from grains (like rice and hemp) and are flavored (like chocolate or vanilla almond milk). “While traditional milk is considered a carb food, it also has about eight times the protein of many plant-based versions and half the carbs of grain milks,” says Emmie Satrazemis, R.D., California-based registered dietitian and nutrition director at Trifecta Nutrition. Plus, it’s the protein content in cow’s milk that’s thought to help control blood sugar response, she adds.
Look for unsweetened options and check the carb count before you buy—one serving of rice milk, for example, can contain roughly 26 grams of carbs. If you opt for a higher sugar choice, either limit your portions or balance out the meal (by mixing it into oatmeal and peanut butter, say, or blending it into a protein shake).
Sure, bananas are packed with important nutrients, such as potassium, vitamin B6, and fiber, but compared to other fruits, they tend to be higher in sugar. “Some bananas have a glycemic index value comparable to honey, and can rapidly increase blood glucose, particularly in those who are carb-sensitive,” says Edwina Clark, R.D., head of nutrition and editorial content at Raised Real. (Here are 9 more fruits and veggies that aren’t as nutritious as you might think.)
Starting with half a banana and seeing how your blood sugar responds can help you nail down a portion size that agrees with you—or, instead of eating a banana on its own, pair it with 2 tablespoons of peanut butter or a handful of nuts, suggests Clark. Protein and fat tend to move slowly through the digestive tract, helping to offset the blood sugar increase.
“Açaí isn’t a natural source of protein and is often mixed with a sweetener to give it a more palatable taste,” says Satrazemis. Add to that the traditional high-carb toppings like granola, fruit, and honey, and this popular pick can be a major contributor to blood sugar spikes. Balance the scales by adding protein powder to your bowl, skipping the added sugar wherever possible (peace out, honey drizzle!), and topping it with lower-carb fruits (strawberries) and healthy fats (nut butters, chia and hemp seeds).
Many people consider frozen yogurt to be a healthy alternative to ice cream—however, it can contain just as much (or even more) sugar, says Florida-based registered dietitian Carol Aguirre, R.D. In fact, manufacturers often add more sugar to balance out the yogurt’s tart taste.
Per 1/2 cup serving, frozen yogurt contains roughly 17 grams of sugar, while ice cream contains 14 grams for the same serving size. Ice cream does contain more fat than frozen yogurt (roughly 3 grams more), but this isn’t necessarily a bad thing: “Fat can slow the body’s digestion of sugar, meaning you’ll feel more satisfied and won’t experience as rapid a blood sugar spike as you might after eating frozen yogurt,” says Aguirre. If you’re a sucker for fro-yo, seek out brands that contain real ingredients and not a laundry list of preservatives or thickening agents, she says, and try to keep your servings to 1/2 cup to help keep your blood sugar in check.
Store-Bought Salad Dressing
Food companies tend to cram sugar into their vinaigrettes and salad dressings—use just 1/4 cup of certain dressings, and you could be sweetening your salad with a full tablespoon of sugar, says Aguirre, which won’t exactly do your blood glucose levels any favors. When buying salad dressing, check the labels and seek out dressings with 0 to 2 grams of sugar per serving, she says—or, stock up on quality oils and vinegars to make your own vinaigrettes and cut out the added sugars completely. Or just make your own.
Beans are an excellent source of protein, fiber, micronutrients, and prebiotics that can nourish the gut microbiome, says Moreno. However, they’re still high in carbs—which means if beans are used as a protein source in a meal that also contains other carbs, the odds of a blood sugar spike increase (especially if you’re carb-sensitive). “Beans should be enjoyed as part of a meal with another protein source, like chicken, fish, or eggs, to potentially lower their glycemic effect,” Moreno suggests.