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Randall Evans, MS, RDN, LD

Is Keto Safe? How To Decide If It’s Right For You

For some, there is a great deal of uncertainly regarding the keto diet. Eating high-fat can seem scary, so here’s what to know before going keto.


Studies show that the keto diet can help you lose weight. It’s generally safe for most people, but it’s not a healthy choice for people who suffer from certain medical conditions.

There’s been a lot of debate about whether or not keto is good for you.

And it can be hard to sift through conflicting data when you don’t know what’s truly right or wrong.

Here’s what you need to know about the safety of the keto diet.

  • Keto diet is safe and proven to work for short-term benefits, like weight loss.
  • Keto diet isn’t safe for pregnant women and people with kidney and liver complications without approval from a doctor.
  • There are side-effects during the transition to keto, but they are manageable.

On one hand, we know keto has been proven to help the masses lose weight, blast fat, and feel better within a few weeks.

Yet on the other hand, keto restricts carbs and limits certain food groups, like fibrous beans and legumes, as well as healthy whole grains. On top of that, you’re increasing your fat intake to make up the bulk of your diet. Where does that fat go exactly?

And how can you make sure you’re getting what your body needs and staying healthy with such carb restriction and high amounts of fat, while still losing weight? Here are the facts.

Is the Keto Diet Safe?

In a nutshell, it’s totally safe to use the standard keto diet as an effective plan for rapid weight loss and health perks!

There’s been a great amount of research done on its ability to help you shed weight fast and provide more energy in the day. As shown in studies, you can thank ketones for that. Due to the body’s use of ketone production as a means for fuel, it helps provoke weight loss and trim body fat more effectively. Your body’s normal metabolic process of using fat for fuel is called “ketosis” and it’s completely natural and safe.

As you practice keto and your body begins using fat to burn fat you’ll naturally feel better, lighter and healthier. Plus, new research shows that keto might even help lower risk of the flu this winter, as a keto-based diet can fire the immune system to ward off illness and fight infection. (Though don’t forgo your flu shot based on this info!)

Is Keto Healthy Long-Term?

Keto has not shown any real adverse, worrisome side effects for overall health, but more research is needed to completely confirm the long-term safety of keto. The good news is research is continually coming forward, as it’s such a hot, trendy diet that shows so much promise and powerful results!

So as long as it’s done in the short-term (3-6 months) and there’s physician approval—you can safely grab that avocado, chicken, steak, and grass-fed butter and hop on board!

And while many have stuck to the diet and reaped the rewards beyond the 6 month mark, more research is needed to determine the sustainability of long-term keto. Luckily, you don’t need to be on keto forever in order to achieve your goals! And if you come off, it’s about coming off in the right way to keep your results.

Bottomline: as long as you get approval from your physician or dietitian to give it a go, you can definitely try keto without worrying about any dangerous side effects. (Of course, with any lifestyle change there are some minor side effects, but we’ll discuss that in-depth in another post.)

Is Keto Right For You?

As with any “diets,” keto might not be the right one for you.

While many have found success with this diet, practicing keto may have potential drawbacks.

Research is still being studied to determine how keto truly works and who it works best for. Time will tell the long-term effects of keto!

This same research also confirms what we’ve always known—the benefits of eating plant-based foods, like whole grains, beans, and legumes are unmatched. Unfortunately, these foods are somewhat restricted on keto due to high carb counts.

So, as with any other diet or lifestyle, it’s important to consider your specific health conditions and to talk to a medical professional before deciding to go full-on keto.

If you’re still not sure whether keto is right for you, read our previous post to learn more about how the keto diet works.

General Keto Diet Guidelines

That being said, keto might be better or worse for some than others depending on their specific goals, conditions and lifestyle.

Who should avoid keto?

If you suffer from medical conditions of the pancreas, liver, or thyroid, you might need to confirm the safety of keto from a doctor before trying it out.

As the high amounts of fat can cause stress to these organs, such nutrient breakdowns of the keto diet might not be the best diet plan for you.

Plus, going keto might not be healthy for women who are pregnant, either. According to research, it could disrupt embryonic development and growth, which could lead to complications with the fetus that could extend until later in life. So, it’s best to avoid it to keep your baby safe.

What’s more, if you are someone who doesn’t do well on restrictive diets that include counting carbs and limiting certain food groups, it could be hard to follow and enjoy.

Yet, if you can get past that as you start to feel the benefits, you’ll build momentum to keep going!

Who could benefit from keto?

The keto diet is effective for those with blood sugar complications. According to a recent study it helps in various conditions such as:

  • Diabetes
  • High cholesterol
  • Blood pressure
  • Heart disease

Where it allows the body to run more efficiently and can lead to weight loss and balanced blood sugar levels.

Since the body uses fat over glucose for fuel, you can avoid blood sugar spikes, decrease cravings for sugary items, and lower total sugar intake in general, too, all of which is great for your ticker.

And if you’re training, you might want to try keto, too. It’s also good for athletes, since you’re ditching high-sugar foods, which can lead to energy “crashes” and fatigue. By eating more wholesome foods that are low in refined carbs and sugars, you’ll have more stamina and endurance for muscle gains.

And if you’re eating a good amount of healthy fats and moderate protein, you can build strong, lean muscles, too. It’s way better than a post-workout snack of refined carbs and sweets!

The Risks of the Keto Diet

As with any diet, there are risks.

For the keto diet, risks include dehydration and nutritional deficiency, but taking the right measures to get enough nutrients and calories in the day and to drink ample fluids can prevent them!

But you can avoid them with the right measures!

So, drink lots of water, coffee, and tea to keep the body hydrated, and you might even want to take electrolyte supplements, as well. You can find these from many brands, like Perfect Keto.

Electrolytes will be a handy aid for getting in enough sodium, calcium, magnesium, and potassium, but you should also eat foods high in these nutrients to stay hydrated, too. A few great ones?

  • Leafy Greens
  • Nuts and Nut Butter
  • Chia and Flax Seeds
  • Grass-fed beef
  • Turkey jerky
  • Plain full-fat cottage cheese.

As for calories, speak to a dietitian to figure out how many you need each day to lose weight but also get enough fuel to have energy, focus, and drive in the day and to keep your body running at its prime! Or you can even use a calorie counter on an app, such as the Healthline Calculator, to determine your recommended daily intake.

Still, you might notice some short-term side effects.

As you begin keto you may go through what’s known as the “keto flu,” which happens as you transition from normal eating to the keto diet. However, this will resolve itself within a week or two, so it’s not permanent!

For more serious side effects, you could be at risk of kidney stones or gallbladder issues if you have kidney or liver medical conditions. However, as long as you speak to a physician about the keto diet before embarking on it, you’ll be able to know if you’re at risk or not.

It’s nothing to fret about too much!

Keto Safety: Commonly Asked Questions

Here are some of the commonly asked questions around the short and long term effects of the ketogenic diet.

Is keto bad for your heart?

No! While it’s assumed that high fat is bad for your ticker, it’s really only excess saturated fat, and you can eat unsaturated fats from nuts, seeds, avocados, and fatty fish like salmon for the bulk of your fat content! And saturated fat in excess is good for you, so enjoy grass-fed steak and butter more so in moderation, compared to the other unsaturated sources.

Is keto safe for PCOS?

Yes! In fact, according to a study, going on a low-carb keto diet actually improved symptoms in women with PCOS. So, it could be beneficial! Yet, definitely speak to a physician first, as you should if you have any medical conditions that could be worrisome.

Does keto cause kidney stones?

No, it doesn’t. High-protein diets can put stress on the kidneys, leading to kidney stones, but keto is not a high-protein diet. It is a high-fat diet, and so since you’re eating moderate amounts of protein, you should be fine. Yet, speak to a physician first if you have kidney complications.

Is keto bad for your liver?

No it is not. Excess buildup of fat can lead to damage in the liver, but for the average person on the keto diet, this should not be a worry. If you have liver disease or other complications, you should speak to a physician before going keto, as it might not be advised. However, as long as you eat healthy fats and don’t have any predispositions for liver failure, your liver should be fine!

Is keto safe for women?

Yes, it is. It might be beneficial for women with PCOS in managing symptoms, and it can be helpful for women looking to lower blood sugar levels and cholesterol levels, as well as lose weight. It is not safe for women who are pregnant though, so if you are pregnant, do not go on the keto diet until the baby is safely delivered and you have permission from your doctor.

Is keto bad for your teeth?

No, it is not. In fact, since you are lowering carb and sugar intake, you are actually protecting your teeth. So, you will have healthier gums, teeth, and enamel, simply due to the decrease in sweet and carbohydrate-rich foods. And as long as you drink ample fluids, like water, and practice dental hygiene, such as brushing twice a day and flossing, you can keep your breath fresh and clean. As you adapt to ketosis, bad breath can be a side-effect, but with the right measures, you can prevent it.

To learn more about the ketogenic diet, read our in-depth keto guide for beginners.


Long-term effects of a ketogenic diet in obese patients: This study shows that in a 24-week ketogenic diet (comprised of 30 g carbohydrate, 1 g/kg body weight protein, 20% saturated fat, and 80% polyunsaturated and monounsaturated fat) in obese patients, there was a reduction in weight and body mass index across the board, as well as decreased level of triglycerides, LDL cholesterol and blood glucose, and an increase in the level of HDL cholesterol for the short-term.

Keto diet has potential in military, researchers say: For short-term of 3 months, keto might help those serving in the military, where obesity is common. As a group, participants lost more than 5 percent of body fat, nearly 44 percent of belly, or visceral fat, and showed a 48 percent improvement in insulin sensitivity, which is a marker for higher risk of diabetes.

On the keto diet? Ditch the cheat day, says UBC study: This study says that keto is very effective for weight loss and improving diabetes symptoms and aiding in management; however, that cheat day (or a variation that includes cycling and going out of ketosis regularly), can derail progress. This shows that just one 75-gram dose of glucose, which you can think of as a large bottle of soda or a serving of fries, can lead to damaged blood vessels if you are on a high-fat, low-carb keto diet. So, be careful not to blast your cells with glucose when your body is used to ketosis as a primary state, as it may lead to adverse effects.

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