These keto diet mistakes could actually hurt your health.

If you are on the keto diet, you're probably cutting way back on carbs (down to under 25 net grams a day) and bulking up on fats (to meet about 80 percent of your daily calories), but it's not just a matter of keeping macronutrients in check.

While we're not the biggest fans of the keto diet at EatingWell (learn more about the science behind the keto diet in our beginner's guide), we also want you to do what's best for your personal lifestyle. So if you're going to try the keto diet, make sure you're avoiding these mistakes because they can be detrimental to your overall health.

You're Missing Out on Key Nutrients

Salmon-Stuffed Avocados

It's easy to miss out on key nutrients on the keto diet like electrolytes (potassium, magnesium and sodium), B vitamins, C vitamins, vitamin D and calcium. Many keto dieters also struggle to get enough fiber, since many fiber-rich foods—like whole grains, beans and fruit—are higher in carbs. Make sure you're loading up on high-fiber, low-carb foods like avocado, chia seeds and leafy greens for optimal health. Consider chatting with a registered dietitian to make sure your version of the keto diet is as rich in nutrients as possible.

You're Not Drinking Enough Water

The keto diet has a diuretic effect that can cause changes in your fluid and electrolyte status, especially in the beginning, so it's a mistake to let yourself get dehydrated throughout the day. "Carbohydrates in their storage form (glycogen) are stored along with water. As you decrease your carb intake and deplete these glycogen stores, you lose this water as well," explains Charlotte Martin, MS, RDN, CPT.

Low-carb diets also lower insulin levels, causing your kidneys to excrete excess sodium. "This means you end up retaining less water as well," she says. Dehydration is a common side effect of the keto diet, which is why it's important to stay adequately hydrated. "A good rule of thumb is to drink when thirsty, and aim for at least half your body weight in ounces. Pay attention to the color of your urine as well: if it's a light or clearish yellow, you're drinking enough and if it's a darker yellow, consider upping your water intake," she says.

Thinking All Fats Are Created Equal


The source of fat you're eating matters when on the keto diet. So, it's a mistake to think you can just put butter on everything you eat and load up on tons of saturated fat from red meat. "A ketogenic diet consists predominantly of fat so it's important to pay attention to the type you choose. Foods like butter, bacon and coconut oil are very high in saturated fat, which is certainly not beneficial to heart health," says Lauren Harris-Pincus, MS, RDN, and author of The Protein-Packed Breakfast Club.

If you are committed to keto, choose more healthy unsaturated fats like avocado, olive oil, nuts, seeds and omega-3-rich fatty fish (like salmon). Eat red meat and use coconut oil in moderation. You can still enjoy them, but make the majority of fats come from healthier sources.

You're Just Eating Meat, Eggs and Cheese

One of the appealing parts of the keto diet is the unlimited cheese, but eating large quantities of animal proteins (like steak or eggs) can actually hurt your health. (Eating less meat has been linked to better heart health, increased weight loss and a longer lifespan. Plus, it's better for the environment!)

So if you're on the keto diet, you may want to consider cutting back on your serving size of animal protein. "The max protein should be around 20%, which, on a 2000 calorie diet, is 100 grams per day. Considering you are cutting out almost all carbs, protein and fat are all that's left to eat, but with each ounce of protein providing about 7 grams, that leaves you with about 4-ounce portions at meals," says Harris-Pincus.

That's not much, since you can't fill the rest of your plate with whole grains and other filling carbs. So, that's when you can pile on green veggies, not more protein! Use non-starchy veggies to fill you up and provide much-needed fiber.

Not Paying Attention to Portions

Smoky Grilled Flank Steak on a cutting board

Recipe pictured above: Smoky Grilled Flank Steak

You don't need to "count calories" exactly, but don't think that going on the keto diet means you can eat as many calories as you want a day. Fat has lots of calories per gram, and if you are eating too many, you won't lose weight.

"Keto is not magic, you still need to consume fewer calories than you burn. It tends to work for many people because it's way easier to overeat carbs than protein and fat," says Harris-Pincus. And when you are forced to avoid pizza, fries, chips, sweets, pasta and other foods that are easy to overconsume, calorie intake is generally lower. Yet, "that pound of bacon likely has too many calories to support weight loss," she says. So, get an estimate in mind of what you are eating each day and how those calories are racking up.