Debunking These 14 Keto Diet Myths - Dr. Axe

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Debunking These 14 Keto Diet Myths


Keto diet myths - Dr. Axe

Never heard of the keto diet? Or maybe you have, but are discouraged from ever giving it a try due to some of the keto diet myths you’ve encountered. Below we’re talking about what the ketogenic diet is, what it is not, and what type of results you can expect to get from following the keto diet correctly.

The keto (ketogenic) diet is a very high-fat, very low-carb diet that alters the source of energy your body uses to function. Instead of using glucose from carbohydrates (your body’s preferred energy source) for fuel, you begin using fat — whether it’s fat from your diet, or your own stored body fat. When you eat a low enough level of carbohydrates (usually about 20–50 net grams) for several days in a row, then you enter the metabolic state called ketosis, which is what forces your body to break down fat for fuel.

Ketosis is characterized by the production of ketone bodies that circulate in your blood; ketones become critical for supplying your brain, organs and cells with enough ongoing energy. Since ketosis is very different from the normal metabolic state in which you burn carbs for fuel, it’s necessary to go through a brief transition phase, and some side effects can be expected.

That being said, not every person will experience “the keto flu.” And contrary to popular belief, each person reacts a bit differently to the ketogenic diet. Factors like your gender, age, overall health and physical activity level all affect hormonal health, your metabolism and your ability to adapt to ketosis. Therefore, let’s examine 14 keto diet myths and see what the real truth is.

Debunking These 14 Keto Diet Myths

1. Keto is a high-fat, high-protein diet.

Unlike other low-carb diets, such as the Atkin’s Diet, the keto diet is not particularly high in protein. In fact, protein intake actually must be “moderate” while on the keto diet because this allows you to transition into ketosis and stay there. Too much protein in your diet will actually result in some of the protein being converted to glucose (or sugar) once consumed — and obviously this is counterproductive when it comes to keeping glucose levels very low.


So how much protein do you need? A standard recommendation for following the ketogenic diet is to get about 75 percent of daily calories from sources of fat (such as oils or fattier cuts of meat), 5 percent from carbohydrates, and 20 percent from protein (give or take a little depending on the individual). In contrast, high-protein, low-carb diets might entail getting 30–35 percent (or more) of daily calories from protein. (1)

2. Keto is a weight loss diet only.

No doubt about it, the ketogenic diet can definitely help many people with weight loss and fat burning. (2) But if losing weight is not one of your goals, this doesn’t mean you can’t follow the keto diet and maintain or even gain weight.

Can you gain weight on the keto diet? It’s certainly possible, especially if you don’t follow the diet correctly and aren’t actually in ketosis.

There’s some controversy surrounding the topic of weight loss due to very high-fat, low-carb diets: some people believe that weight loss is due to decreasing calorie intake, while others believe it’s due to the hormonal effects that the diet has. (3) Still, most experts will agree that despite the type of diet someone follows, if calorie intake exceeds someone’s needs then weight loss can still occur, no matter where the calories come from.

The bottom line? If you eat more calories consistently than you actually need, even if the calories are from fat or protein sources, then you may start to see the scale creep up.

Maybe you’re wondering, “If someone is not looking to lose weight, why would they still follow the keto diet”? The benefits of the ketogenic diet extend far beyond weight loss — they also include regulating hormone production, helping to normalize blood sugar, improving cognitive functioning, improving digestive health, and potentially even reducing the risk for certain diseases and disorders like diabetes or heart disease.

3. Health benefit claims are only claims. There’s no science yet.

This couldn’t be further from the truth! The ketogenic diet was originally developed in the 1920s for patients with epilepsy by researchers working at Johns Hopkins Medical Center, and since this time dozens of studies have showed that the diet offers real benefits. As mentioned above, some of the many health conditions that scientific studies suggest the ketogenic diet may help manage include: obesity, insulin resistance, type 2 diabetes, dyslipidemia, high blood pressure, epilepsy, Alzheimer’s disease, muscle loss and even cancer. (4, 5, 6, 7)

4. You can’t exercise on keto.

Exercise is something that’s beneficial for just about everybody, including those on the keto diet. Initially you might feel less energized during your workouts, but this should dissipate as your body adjusts. Even in the midst of high-intensity workouts, the ketogenic diet doesn’t seem to cause any decline in performance. (8)

In order to support your workouts, make sure you consume enough calories in general and plenty of fat. Also give yourself ample time for recovery between tougher workouts.

If you’re really struggling with being active and recovering while on the diet then consider upping your carbs a bit and trying more of a “modified ketogenic diet” that is more flexible. If you plan on fasting while following the keto diet, then save your tough, high-intensity workouts for days/times of the day when you’re more fueled.

5. You will lose muscle mass on the keto diet.

Can you actually gain muscle on the keto diet? Based on results that many people have experienced, there’s good evidence that yes, you can. One study involving active, college-aged men have found that combining the ketogenic diet with strength-training is a great way to build muscle and increase strength. (9) Despite the American Heart Association’s insistence that low-carbohydrate diets result in the loss of lean muscle tissue, there is actually no physiological requirement for dietary carbohydrates for humans and the keto diet doesn’t cause a loss of muscle mass on its own. (10)

Does the ketogenic diet work without exercise? Yes, it should still lead to many health improvements, but exercise will definitely take things up a notch in terms of leading to body composition improvements and health benefits.


Keto diet myths - Dr. Axe


6. Ketosis and ketoacidosis are the same thing… and both are dangerous.

These two conditions are very different and should not be confused. Ketoacidosis is a serious diabetic complication that occurs when the body produces excess ketones (or blood acids). While it can affect people without a history of diabetes, this is unlikely to happen if someone has no history of metabolic dysfunction.


Ketoacidosis can in part be avoided by having diabetics adjust insulin during times of illness and learn how to monitor their glucose and ketone levels carefully. (11) Diabetics can definitely do keto (it may even help reverse diabetes naturally and limit the need for medications!), but they should only do so under the care of a medical professional. (12)

7. Everyone gets the keto flu.

Every person reacts to the ketogenic diet somewhat differently, so it’s hard to say what type of side effects you might experience, how severe they will be, and for how long they will last. Some people transition into ketosis smoothly, while others might deal with more fatigue, brain-fog, digestive issues and sleep-related problems for several weeks (this phase has been nicknamed “the keto flu”).

While these side effects might be uncomfortable, it’s common for them to go away within a couple weeks, so try to be patient. You can reduce the changes that you’ll experience side effects by consuming enough water, salt, fiber and electrolytes (like potassium or magnesium) from vegetables.

8. You will always be low energy on keto.

Many find that after they adjust to being in ketosis their energy and concentration actually increases. Initially your energy might be lower than normal, but it’s likely that this will change. Ketones do a great job of providing the brain with a steady fuel-source, so it’s common to experience more mental clarity, increased focus and more upbeat moods once you get going on the keto diet.

9. You should only stay on keto for short periods of time.

The first time you start the keto diet it’s recommended that you follow the diet for about 2–3 months, then take a break. Give your body several weeks to adjust, then jump back into the keto diet if it’s working well for you. You might choose to safely cycle in and out of ketosis for many months or even years, depending on how you feel.

There’s no specific time limit to the ketogenic diet; it’s all about figuring out what works best for you given your lifestyle and goals. The longest study to date involving the ketogenic diet lasted a full 10 years, in which no significant heart or other risk factors were noted. (13)

10. You can occasionally cheat on keto.

It might not be realistic to expect that you’ll stick to the keto diet guidelines 100 percent of the time. But unlike other diets, where “cheat days” might be encouraged to give you a mental break and even support your metabolism, cheating on the keto diet can cause you to transition out of ketosis.

This may not be a problem — if it’s intentional. As long as you’re aware that it’s happening and you adjust your diet accordingly, cycling out of the keto diet here and there is okay. If you find that you’re no longer in ketosis due to “cheating” and increasing your carb intake, then you can simply take several days to transition back in by upping your fats and cutting your carbs.

11. Like Atkin’s, you should eat any kind of fat on keto diet.

Because the ketogenic diet is not all about weight loss, healthy fats are encouraged, as opposed to any and all types of fatty foods. For example, most people on the keto diet choose to avoid processed meat products that are high in fat like bacon, salami and poor-quality sausage.

If you want to get the most from the diet, continue to “eat clean”; avoid trans-fats, processed foods made with low-quality vegetable oils, fast food, most fried foods, and poor quality meats and cheeses. To get your fats from healthy sources, opt for organic, cold-pressed oils (like virgin olive or coconut oil), grass-fed butter and meats, pasture-raised poultry, wild-caught fish and cage-free eggs.

12. Keto is the same for men and women.

Overall women are more sensitive to effects of dietary changes and weight loss compared to men. It’s definitely possible for women to safely follow the keto diet, and to practice intermittent fasting if they choose, but they should do so more carefully. It’s recommended that women focus on eating an alkaline diet in addition to a keto diet, meaning they include lots of non-starchy vegetables to make sure they obtain enough electrolytes and nutrients. The diet should ideally be approached in step-wise fashion, focusing on alkaline first before adding in fasting and the keto aspect.

Women should also reduce other sources of stress as much as possible and always listen to their bodies. Stress can cause hormonal changes that might make ketosis more difficult to withstand. If you’re a women following the keto diet then always pay attention to how exercise impacts your energy and moods, how much sleep you get nightly, the amount of sunlight exposure you get, your alcohol and caffeine intake, and the level of environmental toxicity you’re exposed to. Make adjustments as needed if you feel run down or overwhelmed by the diet, since pushing yourself too hard may backfire.

13. Intermittent fasting must occur with keto

Intermittent fasting (IMF) is encouraged during the keto diet and may help accelerate results (such as detoxification and weight loss), but it’s not a requirement to achieve or maintain ketosis. Many people find IMF to be easier when following the keto diet because ketosis is known to kill cravings and reduce your appetite. (14)

If you’re feeling less hungry overall — not only due to eating lots of satiating fats, moderate protein and fiber from veggies during the keto diet, but also because ketones tend to curb hunger — then you’ll find that fasting is not as challenging as it otherwise would be.

14. You can’t drink any alcohol on keto.

Some people choose to still consume alcohol in moderation while on the keto diet, especially organic red wine or hard liquor. The key is to keep alcohol intake low-to-moderate and to consume alcohol with a meal that contains plenty of fat and some protein (this helps prevent a blood sugar surge). Drinks that are high in sugar and carbs, such as sweetened mix drinks and most beers, are not good choices.

You’ll want to keep an eye on how alcohol effects you, since everyone reacts a bit differently. If drinking alcohol causes blood sugar levels to rise too much, and this makes staying in ketosis too difficult, then you’ll need to reduce or avoid alcohol to make the keto diet work for you.

Final Thoughts on Keto Diet Myths

  • The keto (ketogenic) diet is a very high-fat, very low-carb diet that alters the source of energy your body uses to function — from burning carbs/sugar to burning fat.
  • Some common keto diet myths are that the keto diet is only beneficial for weight loss, it always causes low energy and other symptoms, it’s unsafe for women or to follow long-term, and that it leads to muscle loss.
  • Despite what you may have heard about the ketogenic diet, it’s safe for most people to stick with long-term (although keto cycling is a good option for many), it can be used to build muscle and gain energy when coupled with exercise, and it has many benefits beyond burning body fat.

Read Next: The Ketogenic Diet Food List

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