The Keto Diet: Your Guide To Ketogenic Eating & Weight Loss

There’s a good reason keto is so popular.

Low-carb, high-fat eating plans like the ketogenic diet have been proven to produce rapid weight loss and a reduction in body mass for those who are obese (1)(2).

Keto provides a number of other health benefits as well, like lowering blood sugar, LDL (“bad” cholesterol) and triglycerides. (3) Those effects are crucial for the prevention of diabetes and heart disease, among other illnesses. (4) There’s even preliminary research suggesting a keto diet may help fight cancer. (5)

A low-carb keto lifestyle calls on you to make big changes to what you eat. After all, bread, pasta, soda, fast food and desserts are all high in carbohydrates. But the millions who’ve lost weight on keto obviously feel the trade-off is worth it.

This guide will explain everything you need to know to get started on a keto diet:

Let’s get into it.

What Is the Keto Diet?

“Keto diet” is shorthand for a ketogenic eating plan. It’s designed to put the body into a metabolic state known as ketosis.

Obviously, that definition doesn’t help very much if you didn’t major in biology or physiology. So let’s start our explanation by putting things into terms an “end user” can understand.

On a keto diet plan, you eat much more fat than you would in a regular, everyday diet. At the same time, you eat virtually no carbohydrates.

That can be difficult at first. Grains, starches and sugars are all carbs, so a rigorous keto diet means giving up everything from bread, pasta and potatoes to soda, desserts and fast food. Most fruits are off-limits, too.

General keto guidelines (there are different variations on the diet) say that only around 5% of your daily calorie intake should come from carbohydrates. By contrast, U.S. government guidelines suggest that carbohydrates make up about 45-65% of your daily calorie intake. (6)

That means the average person following a keto diet would eat no more than 20 grams of carbs each day – approximately one-tenth of what the government recommends.

When you put this into real world terms, the difference becomes obvious.

A piece of white bread contains about 15 grams of carbs, a can of soda contains about 40 carbs, and a medium serving of French fries contains around 50 carbs. So on keto, a piece of bread uses up almost all of your carbohydrate allowance for the day. Soda or fries? Not on a standard keto diet.

Here’s the other half of the equation. Cutting carbs eliminates about half the calories you’d normally consume each day. How do you replace them? You do it by eating 2-3 times as much fat as usual.

Getting rid of bread and soda makes sense. But why would you eat a lot of fat – when you’re trying to get rid of body fat? We’ll get to the scientific explanation shortly.

What’s important, though, is this: the right percentages of carbohydrates, fat and protein actually force your body to burn stored fat.

This isn’t just a theory or a fad. Versions of the ketogenic diet have been around for about 100 years, first used as a treatment for epilepsy and popular for many years as the Atkins diet. (7)  Modern-day research has shed a lot more light on the body’s metabolic functions, and explains why a keto diet is so effective at producing weight loss. (8)

It’s time to take a brief look at the science, but don’t worry. It will be painless. And there won’t be a quiz.


The keto diet is a high-fat, low-carbohydrate diet which calls for big changes in what you eat each day. Keto actually alters the way the body functions, forcing it into a metabolic state of ketosis. At that point it burns stored fat instead of carbs, to obtain the energy it requires.

What Is Ketosis?

The easiest way to understand ketosis – the keto diet’s golden ticket to weight loss – is to go step-by-step. If you don’t really care about the “why,” just skip to this section’s summary.

  1. The body normally gets energy by breaking down the carbs in your diet. It changes them into glucose, also known as blood sugar, which powers the metabolism.
  2. If there’s leftover glucose, it’s stored in the liver and muscles in a form called glycogen.
  3. When you don’t consume enough carbs to meet the body’s fuel needs, it has to find a different energy source.
  4. First, it uses stored glycogen.
  5. If that’s still not enough, the body has to find another alternative.
  6. Here’s what happens. The stored fat in your body is broken down and turned into molecular compounds called ketone bodies, or ketones for short. The body can run just fine on ketones when glucose isn’t available.
  7. If the body doesn’t get more carbohydrates to burn, it keeps burning stored fat instead.
  8. And that metabolic state, when the body is relying on ketones for fuel, is called ketosis.

Why is ketosis the “golden ticket” to the weight loss we mentioned? Because the key to losing weight is burning stored fat. That’s exactly what the body is doing when it’s in ketosis.

The fastest way to reach ketosis is by fasting. However, that’s not a healthy long-term eating plan. And intermittent fasting will simply put you on a treadmill where you get into ketosis and then fall back out.

The keto diet is designed to put the body into ketosis and keep it there. As long as you only consume a small amount of the “right type” of carbs, your body remains in ketosis – and you lose weight.


The body normally gets energy by breaking down carbs into glucose. Keto diet guidelines deprive the body of almost all carbs, so it turns to an alternative energy source called ketones. They’re produced when the body burns stored fat, leading to weight loss. When the body continuously relies on ketones for energy, it is said to be in ketosis. If followed properly, the keto diet puts the body into ketosis and keeps it there.

How to Know When You’re in Ketosis

There are two ways to know that you’re doing things right and your body has achieved ketosis.

One method is scientific. You can use home testing kits to check your blood, urine or breath for ketone levels.

The other way to know if you’re in ketosis is by the physical signs.

All of these symptoms show that you’re entering ketosis. Once you’re there, they’ll go away.


Blood, breath or urine tests can confirm when you’re in ketosis. But you more easily can tell that you’re entering ketosis when you suffer with “Keto Flu” symptoms like exhaustion, cramping and frequent urination. Stomach problems, bad breath and increased thirst are also common. When those symptoms ease or end, your body is in ketosis.

Losing Weight on the Keto Diet

There’s very little argument: keto helps people lose weight. (9)

The primary reason why the ketogenic diet works? It forces the body to burn fat. The question most people want answered, however, is how much they can lose.

The honest answer is “it depends.” Factors like body weight and composition, overall health, and how rigidly you follow the diet all play major roles.

Scientific research doesn’t guarantee how much you can expect to lose on a keto diet. But some studies and vast numbers of anecdotal reports show that it’s quite possible to lose 1-2 pounds per week (after an initial weight loss of 5+ pounds of water weight).

What research does tell us is whether keto is the best diet for weight loss over a short period of time.

A number of studies have shown that a ketogenic diet is a better choice for weight loss than a traditional low-fat diet (10)(11)(12) or a Mediterranean diet (13). The difference in weight loss varies by study, but participants in controlled research lost an average of 2-5 pounds more on keto, than those on a low-fat diet.

Some claim, though, that the weight loss on keto is due to lower appetite and not fat burning (14), since most people who follow a keto diet experience a significant decrease in their appetite. (15)

Two factors are believed to lower your appetite when you’re on keto. First, ketones suppress hormones that stimulate the appetite (like insulin and ghrelin), while increasing another hormone (known as cholecystokinin) that makes you less hungry. (16) Second, the increased amounts of protein and fat you eat on keto make you feel full. (17)


The keto diet works because it induces the body to burn stored fat, and because it lowers the appetite. No one can accurately predict how much weight you will lose on the keto diet, but studies show that keto is more effective than other common diets like low-fat or Mediterranean diets. Preliminary research and anecdotal reports point to an average weight loss of 1-2 pounds per week.

Other Benefits of the Keto Diet

Weight and fat loss are just some of the benefits of a ketogenic diet.


Low-carb diets are often recommended for type 2 diabetics, and the keto diet has been shown to be particularly effective for both diabetics and prediabetics. In multiple studies it’s been found to produce weight loss, while reducing blood sugar levels and free fatty acids. Studies have also shown keto reduces cholesterol and triglyceride levels, and can improve glycemic sensitivity by as much as 75%. (18)(19)(20)

Better glycemic control on a keto meal plan allowed most patients in several trials to reduce or completely discontinue their diabetic medications. (21)(22)

Metabolic Syndrome and Heart Health

Metabolic syndrome (also known as syndrome X) is a combination of conditions closely linked to obesity and diabetes. Those conditions include excess body fat, plus cardiovascular risk factors like high blood sugar, high levels of “bad” cholesterol and high blood pressure. (23)(24) They often occur together, and dramatically increase a person’s risk for heart attack and stroke.

Improving these metrics is key to the treatment of metabolic syndrome (and important for overall heart health). A keto diet has been shown to lower them all. (25)(26)

Neurological Issues and Epilepsy

Preliminary clinical trials and animal studies have shown promise for the treatment of neurological problems with ketogenic eating plans. Among the conditions which may benefit from a very low-carb diet: Alzheimer’s disease, Parkinson’s disease, and traumatic brain injuries. (27)

Those studies were largely motivated by the successful use of keto to treat epilepsy. A version of the keto diet has been used for decades to treat seizures caused by childhood epilepsy, and in recent years it has been used successfully to treat adult patients as well. (28)

Other Possible Health Benefits

Research has shown a number of additional potential health benefits to the keto diet. They require additional study, but the possibilities include:


Evidence is limited at best, but ketogenic diets show promise for a wide range of serious and even critical illnesses ranging from IBS to cancer. Studies and clinical trials continue.

Types of Keto Diets

There isn’t a single set of universally-accepted keto guidelines. We’re basing this discussion on what’s often called the “standard” ketogenic diet with very low cabs, high fat and moderate protein levels.

You’ll also see references to keto 2.0, moderate keto, therapeutic keto, high-protein keto, very-low-carb keto, MCT keto, Mediterranean keto, targeted keto, cyclical keto, clean keto and “dirty” (or “lazy”) keto.

Dirty keto is the way some people “cheat” on a keto diet, which can work if you’re careful but can knock you right out of ketosis if you aren’t. By contrast, clean keto focuses on high-quality and organic foods. High-protein, targeted and cyclical keto are versions designed primarily for athletes or workout warriors, because vigorous exercise (especially anaerobic exercise) makes unusual energy demands on the body.

The others are variations on the standard keto diet, with different emphasis on the types of foods you can eat. No research has shown one to be better than another, but standard keto is most-commonly followed, and the one for which most keto recipes are designed.


There are many varieties of keto eating plans, but guidelines for the standard keto diet are the ones normally followed when the phrase “keto diet” is used.

The Basics of Keto Eating

We’ve already looked at the overall guidelines for a standard keto diet. As a reminder:

Carbohydrates: 5%
Healthy fat: 75%
Protein: 20%

However, that doesn’t mean you can eat any carbs you’d like. Keto also deals with the types of carbs you should be eating – as well as the types of fat and protein to include on your diet.

Here’s a little more detail.


How do you know what “5% of daily calories from carbs” even means?

First, let’s define carbs. They’re basically starches and sugars. Processed and packaged foods contain enormous amounts of carbs. But pasta and cereal, potatoes and rice, bread and bakery products, and many dairy products are all high in carbohydrates as well. Those are the “bad” carbs.

On the flip side, vegetables, fruits, seeds and nuts contain lower levels of carbs (usually in the form of sugar). Some are more carbohydrate-heavy than others.

You probably don’t want to spend your days looking up carb content, tracking your food consumption on an app, and then using a calculator to figure out percentages. Thankfully, there are easier ways to do it.

For example, you could count carbs instead of percentages. 5% of the diet means around 20 grams of net carbs per day for most people. (If you’re checking food labels, net carbs = total carbs minus dietary fiber; dietary fiber can’t be digested, so it doesn’t count.)

The even simpler approach is to just eat the right carbs in limited amounts. Don’t worry that you won’t be getting “enough” carbs; the US Institute of Medicine reports that the body doesn’t actually require any carbs at all. (37)

We’ll look more closely at “good” and “bad” carbs shortly.


A diet that’s 75% fat sounds amazing, doesn’t it?

Eating lots of fat is quite a change from the diets promoted by major health organizations like the American Heart Association. They recommend avoiding saturated fat, because it can easily be stored as body fat. (38) However, a number of recent studies have shown that saturated fat and fatty acids are actually “health neutral” and don’t necessarily increase the risk for heart disease or high cholesterol levels. (39)(40)

Not all fats are created equal, though. There are fats you should and shouldn’t eat on the keto diet.

Foods containing polyunsaturated fats that are high in Omega-3 fatty acids, like salmon and eggs, are excellent sources of fat. Monounsaturated fats, like avocados and olive oil, are particularly good for a keto diet.

Trans fats and partially hydrogenated oils, on the other hand, are bad for your overall health and should be avoided. The same goes for highly-processed oils like safflower and corn oils.

A more complete rundown will follow shortly.


Almost all proteins are fair game (please forgive the pun) on the keto diet. The only ones which should be avoided are those which have been heavily processed, and breaded or stuffed meats with hidden carbs.


On a keto diet it’s crucial to keep carbohydrate consumption low, and consume only a limited number of “good” carbs like those found in vegetables. Most fats are fine, except for the unhealthy ones, and just about all proteins are acceptable. The best way to stick to a standard keto diet is to consume no more than 20 net carbs per day.

What You Can’t Eat On Keto: The Specifics

It’s human nature to want to know the bad news first – so here it is. These are the foods you should avoid on a keto diet. Stay calm; you’ll soon see there are lots of goodies you can eat.


Sugar doesn’t just mean the white stuff you put into your coffee. Almost anything sweet has a form of sugar in it, even if it’s called something like corn syrup, cane juice or caramel. Honey and maple syrup are forms of sugar, too.

That means skipping nearly all of the desserts and beverages you’re probably accustomed to eating and drinking regularly. Bakery goods and sweets of nearly all types, soda, fruit juice and ice cream are among them. (Don’t panic, you can make delicious and keto-friendly substitutes for many of them.)

You should also check out ingredient lists for “hidden sugars,” because foods you buy off the shelf usually have some form of sugar in them. Examples include salad dressings, tomato sauce, marinades, energy drinks and flavored water, flavored yogurt, granola bars, applesauce, non-dairy milk and even gummy vitamins. The easiest approach is to avoid packaged or processed foods whenever possible, so you know no sugar has snuck its way in.

Starches and Grains

Wheat-based foods are perhaps the worst of all when it comes to net carb content. They headline the “naughty list” for a standard keto diet, as do most other grains.

Some of the grain-based foods we’re talking about here are bread, pasta, tortillas, cereal and oatmeal. And that doesn’t just mean white bread or white pasta. Whole-grain starches acceptable on some diets are off-limits on keto. So is anything made from corn, buckwheat, barley, oats and sorghum.

Starchy vegetables and plants are a no-go; vegetables that grow below ground are almost all out, as are some above-ground varieties. The list of veggies to avoid includes potatoes (including sweet potatoes), artichokes, corn and parsnips. (A few can be eaten in very small amounts, like carrots and onions.) Rice is on the “bad” list too, as is quinoa.


You may know the word, but not what it means. It’s easier to just list examples of these carb-laden vegetables which are not keto-friendly: all forms of beans, peas and lentils.


Trans fats (including hydrogenated oils) and margarine are definitely not acceptable on a keto diet; in fact, they’re unhealthy for anyone to eat, diet or not. Processed vegetable oils (including safflower, sunflower, corn, soybean, palm and peanut oils) are to be avoided or limited. Be sure they’re not used to cook fried food, either.


Finally, a list that’s much shorter. Skip processed and breaded meats or proteins, and any bacon that has added sugar. That’s about it!


Fruit is often people’s dessert of choice when they can’t have sweets. Sadly, most fruits are high in carbohydrates. Citrus fruits, apples and pears, bananas and grapes are among the high-carb fruits which can throw your body out of ketosis. Dried fruits are usually off the “good” list also, as are frozen fruits which are likely to have added sugar.


Keto guidelines say you should skip non-fat or low-fat dairy products completely. Most semi-soft cheeses (like swiss and cheddar) have more carbs than hard cheeses (like parmesan) so you should limit your consumption of semi-soft cheeses. Processed cheeses like American should be avoided.


Want to live a keto lifestyle? Say goodbye to store-bought barbeque sauce, ketchup and any other condiment or dressing with added sugar. Yes, that means most of the processed salad dressings and marinades you buy at the store are out too, but you can make delicious substitutes (without sugar) at home.


We’ve already pretty much addressed this category, since most people’s favorite beverages contain sugar. There are also a few sneaky ones on the list, like smoothies, cocoa, mixed drinks and beer.

Finally, it’s a good idea to steer clear of “low-fat” or “diet” foods. Almost all of them aren’t good for keto diets, because they use artificial sweeteners which can stimulate the appetite, hurt the gut biome and cause inflammation. A few are even believed to be toxic. A list of sweeteners that are good keto substitutes can be found in the next section.


There’s a long list of foods that are problematic when on the keto diet, but the biggest keys to staying in ketosis are avoiding sugar, starches, grains and high-carb fruits.

What You Can Eat On Keto: The Specifics

A keto diet is mainly composed of proteins, vegetables – and lots of healthy fats. Here are the foods that will get you into ketosis and keep you there.


You can eat almost all meats, poultry, seafood and fish on a ketogenic diet.

When possible, choose meats that have been pastured and grass fed, free range-poultry and wild-caught fish. They’re the least likely to contain antibiotics, hormones or pesticides, and they contain more essential nutrients than meat sourced from commercially-farmed animals.

The best fish and seafood for keto dieters are the ones with the highest levels of Omega 3 fatty acids, including salmon, sardines, tuna and mackerel. Look for fatty cuts of meat like ribeye or strip steak, lamb chops, ribs, pork belly, bacon without added nitrates and skin-on chicken thighs.

Hot dogs, sausages and deli meats are usually OK, although you should check to make sure they haven’t had starchy fillers or sugar added. Leaner cuts and types of meat like chicken breasts are fine but should be eaten in moderation.

Eggs are also on the approved protein list, but it’s best that they’re from free-range or pastured poultry and are high in Omega-3s. Many nuts and seeds are loaded with protein and good choices for a keto diet. They include flaxseed, pecans, Brazil nuts, macadamia nuts, chia seeds and walnuts.


The right dairy products are key ingredients for a keto diet.

Butter and heavy/whipping cream are your friends on keto (just don’t overdo it since they have a lot of calories). Cream cheese, cottage cheese, Greek yogurt and sour cream are all fine as well, as long as they’re eaten in moderation. Stick to full-fat milk instead of skim, and don’t drink a lot of it.

Cheese is one of the foods that always comes to mind when thinking about low-carb eating, since it’s low in carbohydrates and high in fat. But some cheeses are better than others.

Hard cheese like parmesan, asiago and romano usually have fewer carbs than semi-soft varieties like cheddar and swiss, but the semi-soft ones are OK as long as you don’t make them a diet staple. Soft cheeses which are great for keto diets include blue cheese, mozzarella, brie and mascarpone.

Oils and Fats

Butter is always a go-to when cooking on keto. There are also a number of oils which can do the trick when preparing food or dressing salad: extra-virgin olive oil, avocado oil, coconut oil, flaxseed oil, sesame oil and walnut oil. Before we move completely away from the subject of butter, give coconut butter a try. It’s delicious.

There are other healthy fats that are good to use on a keto diet, like ghee and lard.

The best source of fat on keto? Avocado, in all of its forms,

Vegetables and Fruits

Get ready to eat lots of low-carb veggies on a keto diet. That includes just about all leafy greens and green veggies, from lettuce and spinach to kale and broccoli. Salad staples like tomatoes, cucumbers, olives and green peppers are on the “good” list, as are asparagus, cauliflower, cabbage, zucchini and Brussels sprouts. Onions and carrots are higher in carbs and should be eaten sparingly.

Almost all fruits, sadly, are high in carbs. You’ll basically be limited to small amounts of watermelon and cantaloupe, strawberries, blackberries and raspberries, star fruit, and perhaps the occasional peach.

Spices and Condiments

You’re good to go with most natural herbs and spices, plus salt and pepper. Hot sauce and salsa are OK if homemade or if they have no added sugar; the same goes for mayonnaise, yellow mustard and salad dressings made with healthy ingredients.

If you’re going to be cooking and are looking for something to use instead of sugar, Stevia is your best alternative. Allulose, Inulin and monkfruit are also good, as are sugar alcohols like xylitol, maltitol and erythritol.


Do you like water? Great, you’ll be drinking a lot of it; flat and sparkling water are both allowed and encouraged. Unsweetened tea and coffee is good, and adding heavy cream to it is even better. When you’re craving milk, substitute almond, cashew or another unsweetened nut milk. An underrated beverage is keto-friendly bone broth.

You can drink kombucha in moderation, but be aware that it will eat up much of your carb allowance for the day. The same goes for diet sodas – but unfortunately, one soda usually makes you crave another one. It’s best to stay away.

We’re just about finished with these lists and at this point, you may need a drink. Just stick to carb-free alcoholic beverages like rum, vodka, gin, tequila and whiskey, and be aware that the carbs in most mixed drinks come from the mixer, not the alcohol. A glass or two of wine is fine every once in a while, as is a light beer.

If you need a general rule-of-thumb when eating or cooking according to keto guidelines, use this one: fresh is best. Packaged and processed foods are likely to contain sugars and starches and can easily kick you out of ketosis.

The good news: more and more keto-friendly alternative foods are now on supermarket shelves. Substitutes for peanut butter, pasta, hot cereal, salad dressings, pizza crusts and snack foods – all made with keto-friendly ingredients – have become widely available, thanks to the keto diet’s explosion in popularity.


There are a huge number of delicious foods you can eat on a keto diet. It’s not just a meal plan loaded with meat, butter and cheese; when you use lots of low-carb veggies and fats, low-carb alternatives for cooking, or keto-friendly foods sold at the supermarket, the variety of meals you can prepare is enormous.

What about Snacks?

It’s difficult enough to stay on a keto diet. Doing it without snacks can be nearly impossible for many people.

Repurposing some of the ingredients we’ve discussed, however, can let you feel like you’re “getting away” with snacking without cheating on your diet. For example:

The most popular keto snacks are known as “keto bites” and “fat bombs.” Many varieties are sold in stores, but if you want to do a little preparation work the possibilities are endless:

And you’ll be relieved to know that small amounts of high-quality dark chocolate (at least 70% cocoa, 90% is better) are also allowed on most versions of the keto diet. Just make it an occasional treat and don’t go overboard.


You can’t grab cookies or ice cream when you feel the need to snack on keto, but there are a wide variety of sweet and savory snack options – both homemade and store-bought – to keep you satisfied between meals.

Can You Eat Out When You’re On Keto?

The COVID-19 epidemic taught us that eating out isn’t essential. But most keto dieters still crave restaurant meals at least once in a while.

Thankfully, you don’t have to give up dining out when on keto. You just have to pay close attention to the menu.

The most obvious steps are avoiding bread, pasta, rice, potatoes, soda and dessert. Most restaurants are familiar enough with the needs of low-carb dieters that they’ll substitute veggies for the starches, and lettuce for burger buns.

If a meal comes with a sauce you can’t eat on keto, ask your server to have the kitchen hold it. Not sure what’s in a sauce? They’ll be happy to tell you ahead of time. Be aware that the dressings served in restaurants usually aren’t keto-friendly, so ask for vinegar and olive oil instead. You can also ask for some extra butter to melt on your food.

A great way to make keto ordering more comfortable when you get to the restaurant is to check out their menu online first; most eateries now offer full details on their websites. And don’t be afraid to ask your server if the restaurant has keto-friendly meal options. Many do.


Restaurants aren’t off-limits to those on a keto diet, but sticking to the diet (and remaining in ketosis) requires skipping some of the foods you’d normally eat when out for a meal, and a willingness to ask questions about ingredients and options.

How Long Should You Stay on a Keto Diet?

Weight loss is great. But so are the rice, apples and ice cream sundaes that don’t play well with a keto diet.

Many people who start keto have no problem altering their eating preferences. It’s normal, though, that they also look forward to the day when they can have rice or potatoes with their meat, an apple for a snack, or an ice cream sundae with their kids.

That leads to an important question: how long should a keto diet last?

Substantial research hasn’t yet been done on the overall long-term implications of a keto diet. (8) However, there are a number of studies showing that staying on keto for long periods of time may be a bad idea.

No research suggests that a short-term keto diet will cause any of those problems. However, most experts agree that keto is not optional for a permanent approach to eating.

Doctors and dietitians often suggest a maximum of three months on the diet. However, it’s possible to cycle on and off of the ketogenic diet, either by taking a month off, or by following a modified keto plan which lets you eat moderate amounts of carbs one day per week. That minimizes the possible risks (and lets you eat carbs for a little while), and then lets you hop back onto the keto bus for additional weight loss.


There’s no definitive research on whether staying on a keto diet indefinitely can hurt you. Most doctors and experts, though, suggest a maximum of three months at a time, due to lack of evidence on keto’s effectiveness over the long-term and possible risks.

Who Shouldn’t Follow A Keto Diet?

Some groups of people shouldn’t consider a ketogenic eating plan without consulting a physician.


Certain medical conditions may make a keto diet risky. You should always consult your doctor before starting if you have any underlying health conditions.

Possible Side Effects of Keto

We’ve already discussed the Keto Flu, the aggravating collection of symptoms like exhaustion, cramps and frequent urination which are common when your body is first entering ketosis. We’ve also discussed ways to minimize the flu-like effects such as increased hydration and mineral supplements.

There are several other side effects you might encounter when following a keto diet. Most are relatively uncommon or rare, but all have been observed.


A few minor side effects may accompany a ketogenic eating plan, but they’re not serious, many are rare, and most can easily be treated.

Before Starting the Keto Diet

Ready to lose some weight? Ready to start a new, healthier lifestyle?

Here’s how to prepare for the keto diet.

  1. Get comfortable with the guidelines. Dieting is a lot easier if you know ahead of time what you should (and shouldn’t) be eating. Checking lists or websites for “permission” whenever you get hungry gets tedious at best. At worst, you may just throw up your hands and eat whatever’s handy.
  2. A related step: find some keto recipes that look really good to you. That way you can start to get excited about the diet, and will have some tasty meals to look forward to once you start.
  3. Clean up the kitchen. Take the “no-go” foods and tuck them away in the back of a cabinet or put them into a corner of the pantry. That will remove temptation and make your keto cooking simpler.
  4. Take a few test runs. Before trying to get into ketosis, sample a few keto meals to see how you handle them “emotionally.” Have your burger on lettuce instead of a bun. Eat your steak with avocado and cauliflower on the side, rather than fries. Switch out soda for water and bone broth for a few days. These practice runs can help get you psychologically ready for a full keto eating plan.
  5. Make sure you have salt and electrolytes (or electrolyte-rich foods) on hand, so you’ll be prepared to deal with the keto flu and put it to rest quickly.
  6. Be sure you realize, and accept, that any diet can be difficult at first. Be prepared to put the work in – but also give yourself permission to be human; don’t beat yourself up if you fall off the wagon. There’s always another chance to start again!

Frequently Asked Questions

Is keto healthy?

Absolutely, particularly for short periods of time. Just double-check with your doctor first if you’re concerned.

Do I have to permanently give up all the carbs I love?

No. But when you plan to come off of a strict keto diet, don’t overdo it. Maintaining lower carb intakes and consuming healthy carbs are the best ways to stay in maintenance mode without gaining back the weight you lost.

Isn’t ketosis dangerous?

No. You may be thinking of ketoacidosis, a serious condition you can develop when you have uncontrolled diabetes. Ketosis is a perfectly safe metabolic condition and doesn’t lead to ketoacidosis except in extremely rare cases.

What about exercising?

High-intensity workouts may be more difficult, because the body uses energy from carbs for the short boosts of power that high-intensity exercise requires. Keto can boost athletes’ endurance, however, and those who favor aerobic exercise may burn more fat than those who don’t exercise.

Will I lose muscle mass on the keto diet?

It’s possible, since the combination of protein and carbs is what’s most responsible for maintaining or building muscle mass. Some small studies suggest that a few months on keto won’t affect muscle all that much (50), but more research is needed.

Should I take ketone supplements?

It’s usually not necessary, but some people find that MCT oil or exogenous ketones can boost energy and mental focus when on a keto diet.

What do I do if I’m always tired?

That’s when ketone supplements may help. You may also not be in full ketosis, so measuring your ketones with a blood, breath or urine test could be a good idea.

Can vegans, vegetarians or the lactose-intolerant follow a keto diet?

Definitely, but it takes careful planning to ensure you’re getting all necessary vitamins and minerals.