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Thinking about going keto? Research shows a ketogenic diet could help you drop pounds faster than other weight loss plans. And plenty of proponents say going super low carb boosts their energy and helps them think more clearly.
In other words, giving this trendy eating style a try could deliver big benefits. That is, if you know what you’re doing.
There are lots of ways a keto diet can go wrong — and when that happens, you might find yourself feeling pretty crappy. Here are seven common missteps keto newbies make and what you can do to steer clear.
The modern approach to fats is often one of fear and trepidation, but that’s no way to go about the keto diet.
Your body needs fats to replace the lost calories from the carbs you’re skipping — otherwise, your calorie deficit could end up f*cking with your metabolism and hormone function in the long term.
Consuming fats also lets your body know it’s OK to burn fats for energy and gets it used to doing so. It’s time to get over the lifelong hang-up that fats make you fat.
While you should be eating certain fats on the keto diet, not all fats are created equal. Some may well be harmful for your weight loss or health goals, while others can get you closer to the outcome you’re after.
Fats to eat on a keto diet
Prioritize monounsaturated fats (from foods like avocados, fish, nuts, and seeds) and unprocessed oils. Cooking foods in olive oil or coconut oil can support a keto diet without adding an excessive health risk.
Fats to avoid on a keto diet
Some fats can increase your risk of health problems if they become a main source of calories in your diet. These include:
- An excess of meat. While many keto recipes recommend meat, you shouldn’t replace all your food with meat. Cooking meat at high temperatures can produce harmful compounds that could increase your risk of cancer. Processed meat takes the risk even further.
- Trans fats. While they’re in shorter and shorter supply since a 2015 ban by the FDA, are still part of the food chain in farmed animals.
- Processed vegetable oils. According to a 2016 study, the process of continually heating vegetable oils generates free radicals, compounds that can contribute to health problems throughout your body.
There’s not much research that confirms the health risks of naturally occurring trans fats, but if you’re essentially swapping your carb intake for an increased fat intake, it doesn’t hurt to be extra careful.
It’s always smart to stay hydrated, but since you’re losing all those extra fluids and minerals, you *really* want to drink up while you’re eating keto.
“Make sure to drink at least 64 ounces of water a day,” suggests Georgie Fear, RD, author of Lean Habits for Lifelong Weight Loss. And if you’re still thirsty, drink more.
Make an effort to replenish those lost electrolytes by eating plenty of potassium– and magnesium-rich foods such as:
You get rid of sodium via your pee, especially when you’re in ketosis, so it makes sense to stay topped up.
As for how to get enough sodium? “Don’t worry about adding extra salt to your food, since most of us get plenty,” Fear says.
But if you really need a boost of salt, you might enjoy a hot cup of bone broth from a health-food store (we promise it tastes better than it sounds).
Think keto diets are all about the protein? That’s not exactly true. Eating keto is actually all about the fat. Now would be a good time to memorize this mantra: It takes fat to burn fat.
“A ketogenic diet essentially swaps the percentages of fats and carbohydrates,” says Robert Santos-Prowse, RD, author of The Cyclical Ketogenic Diet. That means you’ll get 60 to 90 percent of your calories from fat and 5 to 10 percent from carbs.
The remaining 10 to 35 percent should come from protein, which is about the same as standard higher-carb diets. In other words, the goal isn’t to pile your plate with steak or chicken.
So, what should you be filling up on instead? At each meal, aim for 3 to 4 ounces of protein, like lean beef, fish, or pork, depending on your macronutrient needs. Cook with butter or oil (yes, seriously).
Santos-Prowse suggests including 1/2 cup of nonstarchy veggies (like leafy greens, broccoli, or cauliflower) and a few servings of healthy fats (like olive oil, coconut oil, or avocado).
If you suddenly find yourself backed up and bloated after a few days of eating keto, you’re not alone. It’s a thing.
Putting all the focus on fat can make it easy to forget about that other important F: fiber. Add even a touch of dehydration to the mix and you’re looking at the potential for a bad case of constipation.
Since high fiber foods like whole grains, beans, and fruit also tend to be high in carbs, you’ll need to find other ways to get enough roughage. Eat as many high fiber vegetables as you can within your carb limit, Fear says.
Artichokes, broccoli, and brussels sprouts are some good options. Make avocado a mainstay too — it’s one of the few fat sources that also provides fiber. A cup of mashed avo packs 15 grams of fiber, so get at that guacamole.
And remember to drink. that. water.
Eating keto can help you drop pounds, but some experts question whether it’s OK to stick with the diet for the long haul.
“We don’t have long-term data to tell us what happens to humans when they are in a state of ketosis constantly over long periods of time,” says Julie Stefanski, RDN, LDN, a spokesperson for the Academy of Nutrition and Dietetics.
Based on common sense, though, if you decide to stay in ketosis for a long time, you could miss out on important nutrients that some higher-carb foods offer.
So if you plan to live the keto lifestyle, it’s a good idea to talk with a registered dietitian, says Stefanski. They can assess your eating plan to fill any nutritional gaps and help keep possible health problems at bay.
The first few days on a keto diet can feel a lot like having the flu. It’s common to get slammed with a headache, weakness or fatigue, muscle cramps, nausea, diarrhea, or constipation.
When you’re in ketosis, your body breaks down its fat stores to produce handy little molecules called ketones, which it can use for energy instead of the glucose you’d normally get from carbs.
“You’re asking your cells to do something they aren’t used to doing,” explains Santos-Prowse. “When you suddenly deprive them of the fuel they’re used to using, there may be a period of sluggishness or brain fog.”
Another reason you might feel like garbage: Transitioning to keto may also cause your body to shed more water (read: you’ll pee more).
“Especially in the first week of a low carbohydrate diet, your body is shedding a large amount of stored water as it breaks down glycogen in your muscles and liver,” says Fear. “Just like an athlete who sweats heavily loses a large number of salts and minerals, a person excreting large amounts of fluids can also become dehydrated or low on electrolytes like sodium and potassium.”
As your body gets used to this new form of fuel, know that the discomfort is temporary. Most people start to feel better within a few days. Pencil in some self-care, apologize in advance to your loved ones, and adjust your schedule a little (maybe don’t run a 5K during the transition). Hang in there!
Before starting any new nutrition plan, it’s important to know what you’re getting yourself into. The side effects of keto are called “keto flu” for a reason.
To set yourself up for success, give your body time to adjust, drink plenty of water, amp up your electrolytes a bit, and keep your diet balanced. This is not an excuse to eat bacon 24/7, peeps.
You’ll also feel better if you eat low carb foods that are high in fiber (yay, avocados!), stick to the suggested macronutrient ratios, and work with a dietitian to talk about your long-term strategy.