13 Things Everyone Gets Wrong About the Keto Diet

Updated: Mar. 24, 2021

The ketogenic—keto—diet is an increasingly popular eating plan that promises big results. However, it's not the easiest diet to follow, and these early mistakes can sabotage your weight-loss goals.

Woman writing in a notebook.

You don’t track your carbs

The goal of a ketogenic diet is to force your body to stop burning its favorite fuel—glucose from the carbs you eat—and start burning fat stores for energy. The body does this by converting the fats to ketones—a state called ketosis. Keto dieters accomplish this digestive feat by cutting way back on their carbohydrate intake. In fact, the average daily goal for keto is 20 grams of net carbs. But to do it right, it’s not enough to just guess your carb intake. “If you are a beginner to the ketogenic diet, counting carbs is an absolute necessity to avoid frustration in the future,” says Steven Santo, president of Kegenix/Real Ketones, a keto supplement company. Track your food intake with a health app or just use old-fashioned paper and pen. What you learn may surprise you. “You may be wearing ‘carb-blinders,’ meaning you are unaware of how many carbohydrates you are really consuming in a day,” says Santo.

Avocado cut in half.
New Africa/Shutterstock

You aren’t getting enough fat

Keto runs counter to many of the low-fat diet fads of the 1980s and 1990s: It actually emphasizes fat. “That is hard to comprehend because we don’t eat anything that’s pure fat, says Kristen Mancinelli, RD, who practices in New York City and Los Angeles, California. “We don’t eat a stick of butter or a spoonful of olive oil or even a nice cup of lard,” says Mancinelli, who is also the author of The Ketogenic Diet.  “That would be unpleasant, so we really have a hard time wrapping our heads around this concept of the ketogenic diet.” In order to succeed on a keto diet, 60-80% of your food intake will be healthy fats, according to Sara Gottfried, MD, author of the Brain Body Diet. Nuts, seeds, salmon, butter, coconut oil, olives, and bacon are some keto-approved options.

Two salmon steaks.

You’re eating too much protein

Getting your macronutrients—fat, protein, carbohydrates—in balance ensures your body has the best sources of energy. “The ketogenic diet for ‘nutritional ketosis’ is 20 percent protein, 5 percent carbs, and 75 percent fat,” says Jake Crandall, founder and owner of Okie Crossfit in Tulsa, Oklahoma. “If you go too high in protein, you’re effectively on the Atkins Diet and are low-carb. You’ll achieve weight loss, but not the health benefits of being in ketosis.” According to Harvard Medical School, a daily 2,000-calorie keto diet might look like this: 165 grams of fat, 40 grams of carbs, and 75 grams of protein. Of course, the ratio depends on your specific requirements.

Top view of several slices of low sodium Swiss cheese.
BW Folsom/Shutterstock

You don’t eat quality foods

Many unhealthy foods easily meet keto’s low-carb, high-fat criteria. However, that doesn’t mean you can or should eat them freely. “A huge benefit to following the keto diet is that the vast majority of processed food is removed with the removal of grains,” Santo says. “Unfortunately, poor-quality dairy, meat, and veggies may fill the gap.” Look for healthier, better-quality sources of protein and fat. This includes grass-fed meats and limiting processed dairy (think cheese singles) as much as possible.

Meals and snacks portioned out in foil containers.

You don’t plan ahead

Eating out while going keto can be tricky. Planning ahead helps you know where your next snacks and meals will come from. This way, you won’t be tempted to reach for an easy high-carb fix like fast food. Each week, plan out everything from meals to snacks. If you’re using an app, fill in your estimated macronutrients ahead of time. This will help you get an idea of your overall intake, so you can make adjustments to reach your daily goals more easily.

Washed fresh mini spinach.

Your electrolytes aren’t balanced

Your dietary needs change dramatically with keto. Sodium becomes a critical nutrient, as do magnesium and potassium. “At least in the initial stages of being on the keto diet, you will urinate more,” says Carolyn Dean, MD, a naturopathic doctor, nutrition expert, and author of The Magnesium Miracle. “One of the key electrolytes lost through urination is magnesium.” She adds that it’s an energy mineral, which will help you burn fat and lose weight.

Dr. Dean suggests preventing a magnesium shortage by staying well-hydrated. She also recommends adding salt and high-magnesium foods or a magnesium supplement to your day. Foods high in magnesium include almonds, spinach, avocado, and chard.

A bunch of fresh green asparagus on green background.
Roman Pyshchyk/Shutterstock

You eat the wrong vegetables

A lot of veggies are carb-heavy—they can’t fit into an ultra-low-carb diet. These include potatoes of course, but also yams, corn, peas, and carrots. The best options for keto dieters include asparagus, bell peppers, Brussels sprouts, leafy greens, and zucchini. “What’s tough for many people to grasp when starting out on a ketogenic diet is that you can’t really eat a lot of [certain] vegetables,” Mancinelli says. “When you’re keeping carbs super low, you have to limit vegetables—which goes counter to everything you know about how to eat healthy and lose weight.”

Dieters and healthy eaters are programmed to get vegetables at every meal in order to reach their daily plant quota. However, Mancinelli says the cumulative total can blow through your daily net carbs. “The carbs in all those vegetables add up,” she says. “A few carbs here and there with cheese, nuts, and seeds, and you can really miss the mark for ketosis.”

Cashew nuts in white cup on a beige background.

Your fiber intake is too low

While you’re focusing on fat, protein, and carbs, you should also make sure you’re getting adequate fiber. “People often assume that they should only eat things like meat and butter on the ketogenic diet,” says Farshad Fani Marvasti, MD, an associate professor and director of Public Health, Prevention, and Health Promotion at the University of Arizona College of Medicine in Phoenix. “You should make sure you are eating enough vegetables because you need the fiber.”

Specific fiber goals will depend on your overall intake, current weight, and weight-loss intentions. Nuts, seeds, avocado, and squash are fiber-rich foods that are high in fat, but lower in carbs. “I see so many clients go for high protein, high saturated fat, and no carb,” says Sunny Brigham, a board-certified nutrition specialist with a private clinic in North Texas. “They become constipated because they aren’t getting enough fiber.”

Sugar cubes.
New Africa/Shutterstock

You pile on the artificial sweeteners

White sugar, honey, and most traditional sugars are out when you’re eating keto because of the high carb counts. While many artificial sweeteners deliver sweetness sans a single carb, that doesn’t mean you should eat them, Crandall says. “We have demonized sugar—rightly so—for causing unneeded insulin spikes,” Crandall says, but “many artificial sweeteners do the exact same thing.”

A measuring tape on a pink background.
Africa Studio/Shutterstock

You give up too soon

You probably expect to see results with keto quickly. Many keto eaters lose a lot of water weight rapidly after beginning this diet. Without carbs to maintain your glycogen (energy) stores, your body burns through them and dumps all the water they hold. That’s the “water weight” you will rapidly lose in the early days of a keto diet. “We see people quitting before they feel all the benefits of being a fat-burning machine,” Santo says. “Some quit even as soon as the first week.” That’s often the result of keto flu. It’s a temporary condition that many keto eaters experience as their body transitions natural energy sources. Keto flu symptoms include mood swings, nausea, headaches, sluggishness, and more.

Female hand taking a glass of water.
Alex SG/Shutterstock

You aren’t getting enough water

You’ve heard this proclamation even before starting keto diet: You need plenty of water each day for your health. That’s especially true with the keto diet. Without carbs, your body won’t store as much water. Anything you drink passes right through—you can expect to urinate frequently. “Starchy foods have more water retention,” Dr. Marvasti says. “When you avoid these types of foods, you need to make sure you are compensating by drinking enough water.” These 7 clever ways to stay hydrated can help.

Hands typing on a laptop keyboard.

You skip the research

“The biggest mistake people make is that they neglect to do any substantial research into the keto diet,” says Stephanie Lincoln, founder and CEO of Fire Team Whiskey Health and Fitness in Jacksonville, Florida. “They hear about a new fad diet or know someone who has tried it, they do a Google search, read about 10 sentences, then start the plan.” Lincoln recommends taking more time to prepare yourself. Otherwise, the diet may be a total failure. “Basing your behaviors on ‘what I heard,’ or a few sentences read on a random article online is not smart for any health-related question,” Lincoln says. “Do some real research. Read a book or two on the subject.” Here are more things you need to know before starting the keto diet.

Bathroom scale and measure tapes on a blue background.

You focus on the scale

Weight loss for most people will be significant for the first couple of weeks,” Lincoln says. “But just like any eating lifestyle change, your body will adapt and the weight loss will slow down.” Lincoln suggests focusing on “non-scale victories.”

“The argument is that after decades of abusing your body with carbohydrates and thus creating insulin resistance, your body is not going to magically heal itself from a measly 30 days on a low-carb eating plan,” she explains. “If you need things to celebrate while you wait for the scale to start ticking down, look toward your other accomplishments—body composition, pictures, and measurements after three months.”

Give your body time to adjust, and the results will show up and become permanent.

Every product is independently selected by our editors. If you buy something through our links, we may earn an affiliate commission.