15 Foods You Can’t Eat on Keto (and What to Choose Instead)

Sure, croutons are a way to make a pile of lettuce more interesting, but the reality is that on a keto diet, every crumb counts. According to the U.S. Department of Agriculture (USDA), just 2 tablespoons (tbsp) contain 5 g of net carbs, which will severely limit the other veggies and add-ons you can include.

Instead, add crunch with hemp hearts, says Bonnie Nasar, a registered dietitian-nutritionist with a virtual private practice based in Freehold, New Jersey. Not only are these seeds more nutrient dense than croutons, but you can pile on more for fewer carbs: 3 tbsp of hemp hearts have just 1.4 g of net carbs, according to the USDA. Bonus: Hemp hearts are a rich source of unsaturated fat that can help you meet your fat goals for the day in a healthy way.

Peas are a starchy vegetable with a higher amount of carbs than green nonstarchy veggies, such as broccoli or zucchini. That said, if you have eaten a bowl of them recently, don’t feel bad: “If the food you’re going overboard on is peas, it’s not the worst thing you can do,” says Stephen Herrmann, PhD, the director of the University of Kansas Weight Management Program in Kansas City. Just know that because they have 12 g net carbs per cup, per the USDA, they’re likely to put you off track on keto.

Try to stick to nonstarchy veggies. According to the USDA, per cup, broccoli contains 3.7 g of net carbs, zucchini has 2.6 g of net carbs, and raw spinach has 0.4 g of net carbs per cup. While you’re cutting carbs, it’s important to use your carb allotment to eat high-fiber foods to help keep constipation, an unpleasant side effect of keto, at bay, says Nasar. Nonstarchy veggies are the best way to do this, as they offer the most fiber for the lowest amount of net carbs.

On keto, you’ll eat far more fresh foods than you do on the standard American diet. (The U.S. Department of Health and Human Services notes that most Americans don’t eat enough fruits and veggies, and also eat too many foods high in saturated fat, sodium, and added sugar.) Therefore, the days of focusing on fat-free — and carb-rich — snacks, like pretzels or 100-calorie packs of crackers, are over unless you’re noshing on keto-friendly packaged fare. That said, many people on a keto diet consume foods high in saturated fat and sodium, which aren’t the healthiest choices, so when you do keto, you’ll want to choose snacks wisely.

“People are used to eating what’s easy and right in front of them, but there are just-as-easy snacks readily available,” says Nasar. Those include sunflower seeds, toasted pumpkin seeds, and nuts.

Potato chips are out, though you probably already guessed that. A 1 ounce (oz) serving (a measly 22 chips) has about 14 g of net carbs, per the USDA.

Here's a worthy keto- and heart-friendly snack substitute to scratch that salty itch, says Nasar: Finely chop up nuts and seeds in a food processor, and add white vinegar and salt. Roll the mixture up in pieces of nori seaweed (like a cigar) and cook in the oven for 5 to 10 minutes until crispy.

According to the USDA, one banana has more than 20 g of net carbs, which means you may blow your entire allowance on a single one. “We advise people on a lower-carb diet to avoid bananas, particularly in the beginning and when they’re aiming to lose weight,” says Burnison. If you increase your carb goals once you’ve lost weight and are in maintenance mode, you may opt to eat bananas occasionally.

If you want to eat fruit, berries are a good lower-carb choice. You still have to keep portions low, as fruits are naturally higher in carbs. Raspberries are packed with fiber, making them a good go-to. They contain 1.7 g of net carbs per ¼ cup, according to the USDA.

When Nasar recommends the keto diet for folks, she suggests a Mediterranean keto diet, which leans heavily on plant foods. For that reason, while some processed meats are keto-friendly but may not be the most heart-healthy choice (like bacon), others may not be compliant at all with the diet. You’ll want to check the ingredients list first. One that you should avoid is glazed ham. It’s not only considered a processed meat but is also often cooked with a sugar coating. One serving (about 3.5 oz) contains 7.3 g of net carbs, according to the USDA.

If you’re looking for ham, go for a traditional sliced deli ham, which has 0 g of carbs per slice, per the USDA. Still, you’ll want to read the ingredients list to make sure it’s not made with added sugar.

Old-fashioned stick margarines were rich in trans fats, which increase the risk of heart disease, according to Harvard Health. Today, margarine spreads are made from oils like soybean, palm, or palm kernel, which are not recommended on a keto diet.

Nasar suggests using extra-virgin olive oil, because a ton of research backs up olive oil’s heart-healthy properties. Olive oil is rich in monounsaturated fatty acids that temper inflammation and promote blood flow, noted a review published in Endocrine, Metabolic & Immune Disorders in 2018.

If you’re on the diet because you want to lose weight, Dr. Herrmann advises skipping alcohol entirely. “The body chooses to metabolize alcohol first; that, along with a loss of water and micronutrients, increases the risk of dehydration,” he says. If you choose to drink, the worst choice you can make is a blended, frozen drink, which is usually packed with sugar — and thus carbohydrates. As an example, one very small piña colada has 32 g of net carbs, per the USDA. For some people, that represents one and a half days of their carb allotment.

When you’re on keto, you can drink small amounts of alcohol occasionally and in moderation. For the lowest number of carbs, choose a shot of hard liquor and pair it with unsweetened soda water. A vodka soda has zero carbs per drink, notes the USDA.

Even light beers generally pack 6 g of carbohydrates per 12 oz can, as the USDA notes. In the context of keto, a beer means you’ll have to borrow carbohydrates from elsewhere — and if it’s a matter of vegetables versus a beer, the tough — but necessary — choice is the veggies.

If you’ve tried Whole30 or a paleo diet, you may have eaten a lot of sweet potatoes; they're packed with vitamins, minerals, and fiber, but they're a starchy veggie, and you should think twice about them now that you're on keto, says Herrmann. A medium sweet spud has about 20 g of carbs, according to the USDA.

Cauliflower is a fine substitute for sweet potatoes, and it’s frequently used as a replacement for other starchy foods. (Mash them with olive oil and garlic, and voilà, a tasty side!) One cup of cauliflower florets contains only 3.2 g of net carbs, per the USDA.

Whole milk is richer in fat than reduced-fat or skim, but that doesn’t make it keto compliant. One cup of whole has 11.3 g of net carbs, notes the USDA. If you’re making a smoothie, this can derail your goals.

If you really need a liquid base for a smoothie or want to sip on something, go for almond milk. With 1 net carb gram per cup, as the USDA notes, this nondairy alternative can work in your keto diet. Just be sure to read the ingredients and choose an unsweetened variety.

Check out what’s in your trail mix. Are there raisins and other dried fruit? Pretzel pieces? Chocolate candies? If so, that mix is off-limits. A standard 1 oz serving (a small amount, by the way) has more than 12 g of carbs, notes the USDA.

Plain or roasted salted nuts can't be beat as a snack. Nuts have carbs, but they're a great source of fiber, which brings down their net carb count. An ounce of almonds supplies 2.6 g of net carbs, according to the USDA.

They may be packed with vision-friendly vitamin A, as the National Institutes of Health points out, but one medium carrot has 5 g of carbs, per the USDA. If you eat more than a single carrot in one sitting, that small number of carbs can easily tip you over the edge.

You’re better off getting your A from nonstarchy sources like red bell peppers. These can be just as sweet as carrots but contain fewer carbohydrates. An entire small pepper has just 2.9 g of net carbs, the USDA says.

For many people, the keto diet involves a drastic shift in eating — and drinking — habits. If you are a soda drinker, in particular, you’ll want to avoid that, or potentially switch to a diet version, says Herrmann. It may be tough to do at first, but soda is saturated with sugar, and soaking up less of the sweet stuff will benefit your health, whether or not you’re on keto, he says. (Cola has 35 g of sugar per 12 oz can, as the USDA notes.)

Soda was associated with greater odds of death from cardiovascular disease in a study published in Circulation in March 2019. Ultimately, you’re marching toward a healthier pattern of eating, and a registered dietitian who’s knowledgeable about the keto diet can help you figure out how to cut back on or replace these beverages in your diet.

Because it’s carb-free, diet soda is technically an okay option. But sparkling water is an even better choice when you want that fizz, since it doesn’t even contain the artificial sweeteners present in diet drinks. Though technically sugar-free, these sweeteners may stimulate appetite and increase the risk of weight gain, per Harvard Health. Choose naturally flavored but unsweetened sparkling waters, like those from the brands LaCroix or Waterloo. Both have zero carbs.

Butternut squash is another nutrient-packed veggie that simply offers too many carbs for a keto diet. One cup of cubed squash has more than 15.3 g of net carbs, according to the USDA. It’s always a bummer when foods that are nutrient rich (squash is rife with beta-carotene, according to Mount Sinai), versatile, and delicious are off-limits, but the reality of the keto diet is that it does eliminate some traditionally good-for-you foods.

Spaghetti squash can fit into your diet as long as you use small amounts. For instance, as the USDA notes, a ½ cup portion of cooked spaghetti squash as “noodles” amounts to 3.9 g of net carbs (sans sauce).