7 Healthy Foods That Can Actually Make You Sick

Why does eating right sometimes feel so wrong?


Cara Cormack

A few years ago, I was having a lot of sinus issues, so I went to an allergist who tested me for environmental and food allergies. I was convinced the test would tell me I was allergic to dairy and gluten—the big baddies. Instead, it showed I had an intolerance to foods such as salmon, blueberries, bananas, and avocados.

I was allergic to superfoods? Who's allergic to superfoods? I had to eliminate those things from my diet and then slowly reincorporate them over time. Luckily, most of the sensitivities went away, but I did learn a lesson: Foods that are deemed "healthy" aren't necessarily healthy for you, especially if you have a sensitive stomach. So I spoke to a couple of nutrition experts to find out what good-for-you foods might make you feel not so good.

01 of 07

Cruciferous Veggies


Cara Cormack

Before you dip into that crudite platter or broccoli slaw, consider whether those raw veggies might give you an upset stomach. "Cruciferous vegetables like cabbage, broccoli, and cauliflower are rich in anti-cancer compounds like indoles and sulforaphane," explains LA-based nutritionist LeeAnn Weintraub, MPH, RD. "But they also contain a high amount of insoluble fiber which, especially when consumed raw, can cause digestive upset including gas, bloating, and cramps." You don't have to skip these nutritional powerhouses entirely, but try roasting, sautéing, or steaming your veggies in olive oil (to break down some of the hard-to-digest compounds before you consume them). Or cut down on how much you eat in a sitting.

RELATED: 7 Natural Remedies for Soothing An Upset Stomach

02 of 07

Milk and Dairy Products

While dairy may be full of protein and calcium, the lactose could be creating digestive issues for you. In fact, according to the National Library of Medicine (NIH), about 65 percent of the population has a decreased ability to process lactose, an intolerance most common in people of East Asian, West African, Arab, Jewish, and Mediterranean descent. "When an individual eats a food that they are sensitive to, they can experience gastric distress, develop headaches, and notice a lack of energy," explains nutritionist Kristin Kirkpatrick, MD, RDN. Those with lactose intolerance tend to get gas, bloating, and abdominal pain after consuming dairy.

03 of 07

Citrus Fruits

Despite the fact that they're loaded with immune-boosting vitamin C, lemons, limes, oranges, and grapefruits can all mess with your digestion. "If you have certain conditions like heartburn or gastritis, the high acidity levels in these fruits can worsen your symptoms," says Weintraub.

RELATED: 7 Strategies to Form Healthy Eating Habits, According to RDs

04 of 07

Whole Grains

Of course fiber is a good thing to have in your diet. That said, too much fiber can be problematic, causing bloating, pain, constipation, gas, or diarrhea. The recommended amount of daily fiber is about 25 grams for women and 34 grams for men, so don't go overboard on the oats and grains. And try to spread out your intake throughout the day so you don't get an upset stomach. Drinking lots of water can also help to minimize any ill effects.

05 of 07

Spicy Peppers

You may have heard that spicy foods are the secret to longevity, and they do have excellent health benefits: "Spicy peppers like jalapeños are loaded with nutrients and contain a compound called capsaicin, which boosts your metabolism," says Weintraub. But too much of a good thing can have painful results."Some people with sensitive digestive tracts might find that spicy foods worsen their symptoms."

RELATED: 14 Healthy Food Swaps That Taste So Good

06 of 07


If you've ever noticed stomach distress after digging into your avocado toast, you could be sensitive to this superfruit. Avocados are a high-histamine food (which can cause sinus issues in some people), so if you tend to have food intolerances, this could be a problem for you. It was for me, so I can only eat my beloved guac in small doses. Kirkpatrick adds that if you have gallbladder issues, the high-fat content of an avocado could be triggering as well.

07 of 07

Sugar-Free Foods

These days, we're regularly reminded that sugar is the devil, which leads many to flock to sugar substitutes. "Sugar alcohols like sorbitol and xylitol are used as weight-loss and diabetes-friendly sweeteners in everything from sugar-free candy to jams to beverages," says Weintraub. "While these products are considered a more natural sugar alternative [than artificial sweeteners], too much can cause gastrointestinal distress including, gas, cramping, and diarrhea." Some people are more sensitive than others, but if you notice an upset stomach after eating a sugar-free indulgence, consider just treating yourself to the real deal.

RELATED: We Know Whole Grains Are Good for You, but These 11 Are the Healthiest

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