9 Healthy Foods and Drinks You Shouldn’t Binge — and Why

“We always want to incorporate a variety of vegetables, a variety of protein options, and a variety of different fat sources,” says Holly Klamer, RDN, a nutrition educator based in Kalamazoo, Michigan.

The 2020–2025 Dietary Guidelines for Americans from the U.S. Departments of Agriculture (USDA) and Health and Human Services recommend making half your plate fruits and vegetables. And certainly, kale, broccoli, Brussels sprouts, cabbage, and other cruciferous vegetables are loaded with nutrients like folate and vitamin K. But they’re also high in soluble fiber, which contributes to excess gas production, as the Mayo Clinic notes. Eating too much of these vegetables, especially in quantities your body isn’t accustomed to, can cause gastrointestinal discomfort.

Plus, cruciferous vegetables can interfere with how your thyroid uses iodine, Klamer says. Iodine helps your body make thyroid hormones, and plays a role in bone and brain development during pregnancy and infancy, according to the National Institutes of Health.

Eating these vegetables in moderation is likely fine, Klamer says, but having an excess amount every day could be problematic for people who are iodine-deficient, according to a study. But note that cooking the cruciferous veggies lessens the effect on the thyroid.

People who take blood thinners like coumadin (Warfarin) should watch their intake and be sure to check with their doctor if they decide to add more of these vegetables or suddenly cut back, Klamer says, because the vitamin K can impact the medication’s effectiveness. “At least run it past your healthcare team first,” she says.

Avocados, nuts, and olive oil fall into this category. They’re high in monounsaturated fats, which can help improve your cholesterol and decrease the risk of heart disease, according to the American Heart Association (AHA).

Foods with healthy fats are good for you when eaten in moderation, but they’re packed with calories that quickly accumulate.

For example, one avocado contains around 322 calories, according to the USDA, and 1 cup of whole almonds has 828 calories.

Plus, many brands of packaged nuts are “salted with common table salt and sometimes even soaked in vegetable oil,” says Shannon Henry, a San Francisco–based registered dietitian who works with EZCare Clinic, an online healthcare service. That can lead to high blood pressure and increase the risk of heart disease, she says.

Lemon water is a low-calorie, low-sugar way to make drinking water more fun. But lemon is acidic, Klamer points out, and it can damage your tooth enamel and make you more prone to cavities.

“I actually have personal experience with this,” she says. “I went through a phase where I was like, ‘I’m going to start drinking a lot of lemon water,’ and I noticed it made my teeth more sensitive.” Limit other acidic fruits, including oranges, limes, and tomatoes, as well as acidic drinks like lemonade and orange juice for the same reason, advises the American Dental Association.

When sipping lemon water and other acidic drinks, use a straw and rinse your mouth afterward. That can help mitigate any side effects.

Yogurt makes for an easily accessible, nutrient-packed snack, but some brands contain lots of added sugar, says Rachel McBryan, RD, who is based in Nanaimo, British Columbia. That tends to be especially true for lower-fat varieties, “making them more of a dessert than a snack,” she says.

One container of low-fat peach yogurt, for example, typically contains 10 grams (g) of added sugar, notes the USDA. The AHA suggests that women stick to 25 g of sugar per day (which is about 6 teaspoons and 100 calories) and men consume no more than 36 g daily (about 9 teaspoons and 150 calories).

McBryan suggests opting instead for plain, low-fat yogurt and adding your own nutritious fixings, such as fruits and nuts. To take the yogurt itself to the next level, go Greek: This variety contains nearly 20 g of protein per 7-ounce serving versus about half that amount in regular yogurt, notes the USDA.

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Oats contain beneficial fiber, magnesium, and zinc, according to the Harvard T.H. Chan School of Public Health. Yet many brands of instant oatmeal go heavy on sugar, McBryan says. For example, a packet of Quaker Instant Oatmeal Maple and Brown Sugar contains 12 g of added sugars.

McBryan suggests instead making homemade overnight oats: Mix a half cup of plain, raw oats and a half cup of dairy or plant-based liquid, mix, and refrigerate. In the morning, top it with fruit or a tablespoon of peanut butter, she says.

Fish can be a terrific source of protein, vitamin B12, zinc, iodine, and omega-3 fatty acids, according to the U.S. Food and Drug Administration (FDA). An analysis of 20 studies that involved hundreds of thousands of participants found that eating one or two 2-ounce (oz) servings of fatty fish a week reduced the risk of death from heart disease by 36 percent.

But if you eat too much of certain kinds, you may increase your risk of mercury poisoning.

According to the FDA, the best fish choices include catfish, flounder, haddock, salmon, scallops, squid, and tilapia. That’s because they contain the least amount of mercury. Canned light tuna is also a smart choice — it contains 3 times less mercury than albacore tuna, the FDA says. It’s okay to have all these types of fish two to three times a week in a 4-oz serving.

The FDA recommends having other types of fish (those with a medium level of mercury), such as bluefish, grouper, monkfish, and halibut, only once a week, again in 4-oz servings. On the other hand, avoid choices with the highest mercury levels, including king mackerel, shark, marlin, bigeye tuna, orange roughy, tilefish, and swordfish, the agency advises.

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Adequate fiber in the diet reduces the risk of coronary heart disease, according to the USDA’s Dietary Guidelines for Americans. High-fiber foods include chia seeds, berries, black or baked beans, and lentils, the Mayo Clinic says.

But a word of caution: Eating too much too quickly can cause the opposite of the intended effect and lead to constipation, gas, and bloating, according to the Mayo Clinic.

To combat this, slowly increase the amount of fiber you consume, and drink lots of water.

Dark-chocolate lovers reach for their bar for a helping of antioxidants, but this healthier treat isn’t innocent. Specifically, its calories can add up quickly: About 30 g, or 2½ squares, of a typical 90-g dark chocolate bar with 70 to 85 percent cacao contains 170 calories, notes the USDA. Most registered dietitians recommend sticking to 1 square (about 68 calories), especially if you are looking to lose or maintain weight.

Carrots, cantaloupe, winter squash, and sweet potatoes are all high in beta-carotene, according to Mount Sinai. Beta-carotene is an antioxidant that may contribute to immunity and lower your risk of heart disease and cancer, the hospital says, and it plays a role in vision and eye health.

But foods high in beta-carotene contain pigments that can turn your skin yellow or orange, a condition called carotenemia. The discoloring typically happens on thick areas of the skin, like the palms of the hand and soles of the feet, according to a case study. It’s caused by “excessive” and “prolonged” consumption of carotene-rich, yellow- or orange-colored foods, which typically means more than 30 milligrams (mg) of beta-carotene a day, according to StatPearls. (The Cleveland Clinic reports that one carrot has about 4 mg of beta-carotene, so eating about eight carrots per day regularly may result in carotenemia.)

The condition is “unlikely to lead to any serious consequences,” according to the case study. But the study authors noted it’s important to know about the condition so that it’s not confused with jaundice, a more serious condition that causes the skin and whites of the eyes to turn yellow, as the Centers for Disease Control and Prevention notes.

As Klamer says, all these foods can be part of a healthy, balanced diet. “I’m not saying that no one should eat these foods,” she says. “You just want to avoid overdoing it on one.”

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