Achieving and maintaining ketosis can be harder than many people expected. Though it’s not necessarily what you eat that causes trouble, it’s very much about what you don’t eat. 

The keto diet, while simple in theory (low-carb, high-fat), can easily be derailed by seemingly small food choices. A slice of bread, a sugary drink, or even an unsuspecting banana can nudge your body out of the ketosis fat-burning state.

To help you better understand which foods to avoid and which to pick, this guide will help you understand what not to eat on keto and which keto-friendly alternatives will actually help you stay on track, without sacrificing satisfaction.

The Basics: What Goes on in Your Body on a Keto Diet

Before we discuss what foods kick you out of ketosis, it’s essential to understand what makes the keto diet unique and why certain foods have such a big impact.

By reducing your carbohydrate intake significantly, usually to fewer than 50 grams of net carbs per day, your body enters a metabolic state called ketosis. In this state, your liver breaks down fats into ketones, which are used for fuel instead of glucose.

There are many reasons people want to go on a keto diet, most of them rooted in its many powerful benefits: 

• stable energy

• reduced hunger

• improved blood sugar regulation

But it’s also a delicate balance: just one carb-heavy meal can provide enough glucose to kick your body out of ketosis. This halts the fat-burning processes in favor of sugar-fueled energy. 

You can read up more on the ketosis process in our Ketogenic Diet 101, but for now, it is worth looking into the exact foods that will or will not keep you in ketosis.

Foods to Avoid and Include in Ketogenic Diets

Avoid High-Carb Grains and Starches

It’s no surprise that traditional grain-based foods are off the table on keto. Bread, pasta, rice, oats, and potatoes are carbohydrate-rich and known to cause rapid spikes in blood sugar, exactly what you want to avoid when trying to stay in ketosis.

Refined grains can pose a problem because they are more rapidly digested than whole grains and lack the fiber to blunt the glucose (e.g., blood sugar) spike. This means they shift your body back toward glucose metabolism almost immediately.

Common high-carb grains to avoid include:

• white or whole wheat bread

• pasta (even whole grain)

• white rice

• oats

• potatoes (sweet and regular)

Keto-friendly swaps to enjoy instead:

• cauliflower rice

• zucchini noodles (“zoodles”)

• Shirataki noodles (made from konjac root)

• mashed or roasted turnips

Avoid Sugary Foods, Sweet Beverages, and Sweeteners

Sugar is one of the fastest ways to spike your blood glucose and halt ketone production. This includes obvious culprits like candy or soda, but also some of the “natural” options like honey or maple syrup.

Beyond those options, certain foods labeled as “healthy” can pack in hidden added sugars, such as sauces, dressings, granola, and even protein shakes.

Watch out for:

• table sugar and powdered sugar

• honey and agave syrup

• maple syrup

• fruit juice and sweetened drinks

• soda (even some labeled “organic”)

Keto-friendly sweeteners include:

• Stevia

• monk fruit extract

• erythritol

High-Carb Fruits

Fruits may be rich in vitamins and antioxidants, but many are also high in sugar, meaning when on keto, you’ll have to watch your fruit choices closely.

Bananas, grapes, and mangoes, for instance, can contain over 20 grams of carbs per serving—enough to use up your entire day’s limit in one go. Dried fruits tend to be even more concentrated in sugar and should be avoided altogether.

Instead, go for lower-carb fruits that offer flavor, fiber, and fewer net carbs.

Skip these fruits:

• bananas

• grapes

• pineapple

• mangoes

• dried dates or raisins

Keto-approved fruit options:

• sour berries (raspberries, blackberries, strawberries)

• avocados

• coconut (unsweetened)

Avoid Legumes and High-Carb Vegetables

While legumes like beans, lentils, and chickpeas are plant-based and nutrient-dense, they can also be high in carbohydrates. Even certain vegetables can lean too carb-heavy on keto.

High-carb vegetables to limit:

• beans and lentils

• sweet potatoes

• chickpeas and hummus

• corn

• carrots (up to 100-200g)

• beets (up to 100-200g)

Better low-carb vegetable options:

• leafy greens (spinach, kale, arugula)

• broccoli and cauliflower

• asparagus

• bell peppers

• zucchini and mushrooms

While you’ll want to exercise caution, don’t underestimate the value of low-carb vegetables on keto, as they are essential for fiber and micronutrients. These high-volume, low-calorie foods add satisfaction to your meals.

Avoid Hidden Carb Condiments and Sauces

One particularly deceptive source of carbs is found in sauces and condiments. Even small quantities, such as a tablespoon of BBQ sauce or ketchup, may contain 5 or more grams of sugar. While that might not sound like much, it is a tenth of your daily carb limit on a keto diet.

Common high-carb condiments include:

• ketchup

• BBQ sauce

• honey mustard

• sweet chili sauce

• teriyaki sauce

Keto-friendly swaps to try:

• sugar-free ketchup or BBQ sauce

• mustard

• homemade mayo

• pesto

• hot sauce

• full-fat ranch (without added sugar)

Tip: Always read labels. While some condiments are marketed as “light” or “organic”, they often still contain enough sugars to disrupt ketosis.

Avoid Protein Bars and “Health” Foods

“Low-carb” protein bars and snacks may sound safe, but ironically, they might be anything but keto-friendly. Many use sugar alcohols that still impact blood sugar, or list misleading net carb values.

One example to avoid is maltitol, a sugar alcohol that can still spike glucose and insulin levels in many people.

Problematic options include:

• granola bars

• most commercial protein bars

• “low-carb” snacks with hidden sugars or maltitol

Keto-friendly alternatives:

• homemade fat bombs (e.g., with coconut oil, cacao, and nut butter)

• keto-certified protein bars (with verified low net carbs)

• hard-boiled eggs or cheese sticks

Keep in mind that “low sugar” doesn’t always mean keto-safe. Look for products that list total and net carbs clearly, and favor whole food options when in doubt.

Choose Alcoholic Beverages Wisely

Alcohol and keto have a complicated relationship: while some drinks are low in carbs, alcohol metabolism generally halts fat burning, because your body views alcohol as a toxin to eliminate first.

This doesn’t mean you can’t enjoy a drink, but moderation and choice matter.

Alcohols to avoid:

• beer (especially light lagers and wheat beers)

• sweet wines and dessert wines

• cocktails with sugary mixers

• flavored liqueurs

Smarter keto-friendly options:

• dry red or white wine (e.g., Cabernet, Sauvignon Blanc)

• spirits like vodka, gin, whiskey (without sweet mixers)

• sugar-free tonic or soda water with lime

Keep it social and slow, and be aware that alcohol tolerance often changes on keto.

Are All Carbs Bad When You're in Ketosis?

Luckily, not all carbs are bad, though the context matters a lot. Fiber, for example, is a carbohydrate that supports digestion and doesn’t raise blood sugar. That’s why most keto plans calculate net carbs instead of total carbs, which account for fiber content. Or, some people initially opt for modified keto diets to ease into the concept.

Some carbs, particularly those found in leafy greens and low-carb vegetables, also offer essential nutrients and keep the diet sustainable long-term. So, the goal isn’t zero carbs but strategic carbs.

7 Practical Tips to Stay in Ketosis

Because there are differences between low-carb vs. keto-diets, staying in ketosis requires more than just avoiding carbs: consistency, awareness, and a few smart strategies help just as much with its longevity in your life.

Prep Your Meals in Advance

Batch cook keto-friendly staples like cauliflower rice, boiled eggs, or grilled proteins to stay prepared and avoid impulsive choices.

Make Healthy Fats the Star

Think of avocados, olive oil, nuts, and seeds as a central part of your meals. They help you stay full, stabilize energy, and maintain the keto balance.

Prioritize Quality Proteins

Focus on moderate portions of high-quality proteins like grass-fed beef, salmon, or pasture-raised eggs.

Check Labels Religiously

Carbs can hide in sauces, dressings, and “diet” snacks. Always read the fine print—even on “keto” branded products.

Stay Hydrated and Replenish Electrolytes

Ketosis can flush out water and minerals. Drink water consistently and consider adding magnesium, potassium, and sodium to your diet to replenish any lost electrolytes.

Experiment with Meal Timing

Intermittent fasting can help some people enter and maintain ketosis more easily but it’s not required for everyone.

Create a Keto-Friendly Kitchen

Stocking up on essentials and removing high-carb temptations can help reduce friction and decision fatigue.

Wrap-Up for the Keto Diet: What Not to Eat

The ketogenic diet can unlock powerful health benefits, but only if you protect the state of ketosis. By avoiding carb-heavy foods and replacing them with smart, satisfying alternatives, you’ll not only stay in fat-burning mode, but you’ll also make the diet more enjoyable and sustainable.