A ketogenic diet is a high fat and low carb diet. Reducing carbs may put your body in ketosis, which causes it to use fat for energy. This may help with weight loss.
If you find yourself in a conversation about dieting or weight loss, chances are you’ll hear about the ketogenic, or keto, diet. The keto diet has become one of the most popular methods worldwide among people trying to lose weight and improve their health.
If you’ve been thinking about trying the keto diet and have gotten the thumbs up from your healthcare professional, use this article to learn more about what to eat and what to limit while following a keto diet.
The keto diet, as a rule, is very low in carbs, high in fat, and moderate in protein. While you can eat some carbs, you’ll need to monitor your intake.
While different versions of the keto diet exist the percentageTrusted Source of calories a person will consume will be approximately as follows:
- carbs: 5–10%
- fats: 70–75%
- protein: 15–20%
This carb reduction forces your body to rely on fats for its main energy source instead of glucose — a process known as ketosis.
While in ketosis, your body uses ketones — molecules produced in the liver from fats when glucose is limited — as an alternate fuel source. Plus, keto diets reduce hunger and increase satiety, which can be helpful when trying to lose weight.
ResearchTrusted Source shows that ketogenic diets are effective at promoting weight loss — though they may be no more effective than other weight-loss diets.
The ketogenic diet relies on a very low carb routine. Carbs are typically restricted to 20–50 gramsTrusted Source
per day on a 2,000-calorie diet. Instead, you’d eat mostly fat and protein.
Ketogenic diet meal plan
Switching to a ketogenic diet may seem overwhelming, but it doesn’t have to be difficult. Your focus should be on reducing carbs while increasing the fat and protein content of meals and snacks. Some online tools and calculators can be helpful.
In order to reach and remain in a state of ketosis, carbs must be restricted. While certain people might only achieve ketosis by eating 20 grams of carbs per day, others may be successful with a higher carb intake.
Generally, the lower your carbohydrate intake, the easier it is to reach and stay in ketosis.
This is why sticking to keto-friendly foods and avoiding items rich in carbs is the best way to successfully lose weight on a ketogenic diet.
Keto-friendly foods
When following a ketogenic diet, meals and snacks should center around the following foods:
- Eggs: pastured, organic, or conventional all work fine
- Poultry: chicken and turkey
- Fatty fish: salmon, herring, and mackerel
- Meat: beef, venison, pork, organ meats, and bison
- Full-fat dairy: unsweetened yogurt, butter, and cream, but check the labels as dairy does contain some carbs
- Full-fat cheese: cheddar, mozzarella, brie, goat cheese, and cream cheese
- Nuts and seeds: macadamia nuts, almonds, walnuts, pumpkin seeds, peanuts, and flaxseeds
- Nut butter: no-sugar-added peanut, almond, and cashew butters
- Oils rich in healthy fats: olive oil, avocado oil, and sesame oil
- Avocados: whole avocados can be added to almost any meal or snack
- Non-starchy vegetables: greens, broccoli, tomatoes, mushrooms, and peppers
- Condiments: salt, pepper, vinegar, lemon juice, fresh herbs, and spices
Foods to limit
When possible, it’s best to avoid or limit foods rich in carbs while following a keto diet.
The following foods should be limited:
- Bread and baked goods: white bread, whole wheat bread, crackers, cookies, doughnuts, and rolls
- Sweets and sugary foods: sugar, ice cream, candy, maple syrup, honey, agave syrup, and coconut sugar
- Sweetened beverages: soda, juice, sweetened teas, and sports drinks
- Pasta: spaghetti and other noodles
- Grains and grain products: wheat, rice, oats, breakfast cereals, and tortillas
- Starchy vegetables: potatoes, sweet potatoes, butternut squash, corn, peas, and pumpkin
- Beans and legumes: black beans, chickpeas, lentils, and kidney beans
- Fruit: citrus, grapes, bananas, and pineapple
- High carb sauces: barbecue sauce, ketchup, honey mustard, sugary salad dressings, and dipping sauces
- Certain alcoholic beverages: beer and sugary mixed drinks
Though carbs should be restricted, you can eat them in small amounts while monitoring your intake.
For instance, you can enjoy low glycemic fruits, such as berries, in limited amounts as long as you’re maintaining a keto-friendly range of macronutrients (carbs, protein, fat).
Be sure to choose plenty of whole foods and steer clear of processed foods and trans fats when possible.
Keto-friendly beverages
Sugar can be found in a wide variety of beverages including juice, soda, iced tea, and coffee drinks. While on a ketogenic diet, you should limit or avoid high carb drinks, just like high carb foods.
Sugary beverages have also been linkedTrusted Source to various health concerns — from obesity to an increased risk of type 2 diabetes.
There are many tasty sugar-free options for those on the keto diet. Keto-friendly beverage choices include:
- Water. Water is the best choice for hydration and should be consumed throughout the day.
- Sparkling water. Sparkling water can make an excellent soda replacement.
- Unsweetened coffee. Try using heavy cream to add flavor to your cup of coffee.
- Unsweetened green tea. Green tea is delicious and may provide many health benefits.
If you want to add some extra flavor to your water, try experimenting with different keto-friendly flavor combinations. For example, tossing some fresh mint and a lemon peel into your water bottle can make hydration a breeze.
Though alcohol should be restricted, enjoying an occasional low carb drink like vodka or tequila mixed with soda water is acceptable on the keto diet.
The ketogenic diet revolves around high fat, low carb food choices and limits highly processed foods and trans fats. Keto-friendly beverage options should be sugar-free when possible. Consider water, sparkling water, or unsweetened green tea and coffee.
A sample keto menu for 1 week
The following menu provides fewer than 50 grams of total carbs per day. As mentioned above, some people may have to reduce carbohydrates even further in order to reach ketosis.
This is a general, 1-week ketogenic menu that can be altered depending on individual dietary needs.
Monday
- Breakfast: two eggs fried in butter served with sauteed greens
- Lunch: a bunless burger topped with cheese, mushrooms, and avocado atop a bed of greens
- Dinner: pork chops with green beans sauteed in olive oil
Tuesday
- Breakfast: mushroom omelet
- Lunch: tuna salad with celery and tomato atop a bed of greens
- Dinner: roast chicken with cream sauce and sauteed broccoli
Wednesday
- Breakfast: bell pepper stuffed with cheese and eggs
- Lunch: arugula salad with hard-boiled eggs, turkey, avocado, and blue cheese
- Dinner: grilled salmon with spinach sauteed in sesame oil
Thursday
- Breakfast: full-fat yogurt topped with Keto granola
- Lunch: steak bowl with cauliflower rice, cheese, herbs, avocado, and salsa
- Dinner: bison steak with cheesy broccoli
Friday
- Breakfast: baked avocado egg boats
- Lunch: Caesar salad with chicken
- Dinner: pork chops with vegetables
Saturday
- Breakfast: cauliflower toast topped with cheese and avocado
- Lunch: bunless salmon burgers topped with pesto
- Dinner: meatballs served with zucchini noodles and Parmesan cheese
Sunday
- Breakfast: coconut milk chia pudding topped with coconut and walnuts
- Lunch: Cobb salad made with greens, hard-boiled eggs, avocado, cheese, and turkey
- Dinner: coconut chicken curry
Although many ketogenic meals are based around animal products, there are vegetarian options. However, following a keto vegetarian diet will be more challenging, as the choice of foods will be less varied.
Anyone following a keto diet should aim for as much variety as possible in their ingredients to reduce the risk of nutritional deficiencies.
If you’re following a more liberal ketogenic diet, adding a cup of berries to your breakfast or a small serving of a starchy vegetable to your dinner will increase the number of carbs in this meal plan.
A ketogenic meal plan, like any nutritious diet, should include whole foods and many fiber-rich, low carb vegetables. Choose healthy fats like sesame oil, avocado oil, olive oil, and butter to increase the fat content of dishes.
Ketogenic snack options
Snacking between meals can help moderate hunger and keep you on track while following a ketogenic diet.
Here are some excellent, keto-friendly snack options:
- almonds and cheddar cheese
- half an avocado stuffed with chicken salad
- guacamole with low carb veggies
- trail mix made with unsweetened coconut, nuts, and seeds
- hard-boiled eggs
- coconut chips
- kale chips
- olives and sliced salami
- celery and peppers with herbed cream cheese dip
- berries with heavy whipping cream
- jerky
- cheese roll-ups
- Parmesan crisps
- macadamia nuts
- greens with high fat dressing and avocado
- keto smoothie made with coconut milk, cocoa, and avocado
- avocado cocoa mousse
No matter which diet you are following, it’s important to eat the appropriate number of calories based on your activity level, weight loss goal, age, and gender. Working with a nutritionist can help you make sure you get the proper amount of nutrients and calories for your personal goals or health history.
Keto-friendly snacks should be high in fat, moderate in protein, and low in carbs. You can increase your fiber intake by snacking on sliced, low carb vegetables with a high fat dipping sauce.
A simple ketogenic shopping list
A well-rounded ketogenic diet should include lots of fresh produce, healthy fats, and proteins.
Choosing a mixture of both fresh and frozen produce will ensure that you have a supply of keto-friendly vegetables and fruits to add to recipes.
The following is a simple ketogenic shopping list that can guide you when perusing the grocery aisles:
- Meat and poultry: beef, chicken, turkey, and pork
- Fish: fatty fish like salmon, sardines, mackerel, canned tuna, and herring
- Shellfish: oysters, shrimp, and scallops
- Eggs: organic or conventional
- Full fat dairy: unsweetened yogurt, butter, heavy cream, and sour cream
- Oils: olive, sesame, and avocado oils
- Avocados: a mixture of ripe and unripe avocados (so that your supply will last)
- Cheese: Brie, cream cheese, cheddar, and goat cheese
- Frozen or fresh berries: blueberries, raspberries, and blackberries
- Nuts: macadamia nuts, almonds, pecans, and pistachios
- Seeds: pumpkin seeds, sunflower seeds, and chia seeds
- Nut butters: almond butter, sunflower butter, and peanut butter
- Fresh or frozen low carb vegetables: mushrooms, cauliflower, broccoli, greens, peppers, onions, and tomatoes
- Condiments: sea salt, pepper, salsa, herbs, garlic, vinegar, mustard, olives, and spices
It’s always worthwhile to plan your meals ahead of time and fill your cart with the ingredients needed for a few days’ worth of healthy dishes.
Plus, sticking to a shopping list can help you avoid foods that don’t fit within your nutrition plan.
Preparing a shopping list can help you decide what foods will fit into your ketogenic meal plan. Fill your cart with meat, poultry, eggs, low carb veggies, full-fat dairy, and healthy fats.
Benefits of the keto diet
Some researchTrusted Source suggests that adopting this low carb, high fat diet may promoteTrusted Source weight loss and improveTrusted Source glycemic control in people with type 2 diabetes.
The keto diet may also have neuroprotective effectsTrusted Source and help improve cognitive functionTrusted Source in people with Alzheimer’s disease, though more research is needed.
Drawbacks and risks
While the keto diet does seem to have some benefits, it is unlikely to be suitable in the long term. There are some risks and possible drawbacks for people on the keto diet.
Keto Flu: this includes a range of symptoms that can develop when starting a ketogenic diet. This can feel similar to the flu, and it’s caused by the body adapting to a new diet consisting of very little carbohydrates. Your body enters a process known as ketosis, which may cause you to experience other symptoms that include leg cramps, digestive issues, and bad breath. Ketosis is safe and healthy, but may not be for everyone.
Weight regain: While it may help you lose weight, stopping can lead to weight regain.
Not for everyone: The keto diet is not recommendedTrusted Source for everyone. This may include people with kidney failure or liver disease, as well as type 1 diabetes as it can lead to diabetes-related ketoacidosis. Make sure to consult your healthcare team before beginning the keto diet.
Cholesterol impact: A keto diet is typically high in saturated fat and trans fats. These can raise LDLTrusted Source (“bad”) cholesterol in some individuals, which may increase the riskTrusted Source of cardiovascular disease and cardiovascular events like heart attack and stroke.
Fiber and vitamins: It can also be low in vegetables, grains, and legumes, meaning you may not get enough fiber and B vitamins to maintain essential body functions.
Restrictive: The diet is very restrictive and needs careful planning, which makes it hard to sustain. The lack of diversity can lead not only to nutritional deficiencies but also boredom. It can affect social events, as eating out becomes more difficult.
Pregnancy and nursing parents: It may not be safeTrusted Source for those who are pregnant or nursing.
For these reasons, it’s best to check with a health professional before trying a keto diet.
Summary
A ketogenic diet may help manage weight and glucose levels, among other benefits. However, it also involves a high fat intake, and may not be suitable for everyone.
Frequently asked questions
What do you eat on a keto diet?
Depending on the precise keto diet you choose, carbs will make up 5–10%, fats 70–75%, and protein 15–20%. Examples of foods you can eat would be a mushroom omelette, chicken curry, yogurt, nuts, and seeds. It’s best to get your carbs from fruits or low-carb vegetables.
What are the basic rules of keto?
People who follow a keto diet focus mainly on high-quality fats and proteins while keeping carb intake to 5–10% of their total calories. To benefit from the diet, you’d need to opt for less processed foods such as nuts and fresh fish.
What are the main foods to avoid on a keto diet?
Foods to avoid include carbs, and particularly highly processed carbs, such as white bread, cookies, and so on.
Bottom line
Ketogenic diets vary but will consist of about 70–75% fat, 15–20% protein, and 5–10% of carbs per day.
Focus on high fat, low carb foods like eggs, meats, dairy, and low carb vegetables, as well as sugar-free beverages. Be sure to limit highly processed foods and trans fats.
The popularity of the ketogenic diet has made it easier than ever to find a wide array of interesting and healthy keto meal ideas online.
Because the keto diet may not be advisable for those with high cholesterol or who are living with heart or liver disease, be sure to consult a registered dietitian, physician, or other qualified healthcare professional before starting the keto diet to ensure it is safe for you.
7 Tips to Get into Ketosis
Cutting carbs, increasing your intake of healthy fats, and getting more exercise may help you enter ketosis.
Ketosis is a normal metabolic process that provides fuel for your body at times when fewer carbohydrates are available. Nutritional ketosis may offer health benefits.
During nutritional ketosis, your body converts fat into compounds called ketones and begins using them as its main source of energy. Ketones are also known as ketone bodies.
Diets that promote ketosis are highly beneficial for weight loss, partly due to their appetite-suppressing effects. Ketosis may also be helpful for type 2 diabetes and neurological disorders, among other conditions.
But getting into a state of ketosis can take some work and planning. It’s not as simple as just cutting carbs.
There is still debate about the long-term safety of the ketogenic diet. Before making major dietary changes, such as trying a ketogenic diet, it’s important to consult a qualified health professional. This is especially the case for children, those who have underlying health conditions, and those who are pregnant or breastfeeding.
Potential risks of this style of eating include nutritional deficiencies, kidney stones, changes in electrolyte levels, and bone loss.
Here are 7 effective tips to get into ketosis.
. Minimize your carb consumption
Eating a very low carb diet is by far the most important factor in entering ketosis.
Your cells typically use glucose (sugar) as their main source of fuel. However, most of your cells can also use other fuel sources, including fatty acids and ketones.
Your body stores glucose in the form of glycogen in your liver and muscles.
When your carb intake is very low, your glycogen stores are reduced and your levels of the hormone insulin decline. This allows fatty acids to be released from fat stores in your body.
Your liver converts some of these fatty acids into the ketones acetone, acetoacetate, and beta-hydroxybutyrate. Portions of your brain can useTrusted Source these ketones as fuel.
The degree of carb restriction needed to induce ketosis varies by the person and can be affected by certain factors, such as the types of exercise you do.
Some people need to limit their net carb intake to 50 grams (g) or fewer per day, while others can get into ketosis while eating more than that.
For this reason, the induction phase of the Atkins diet requires restricting carb intake to 20 g or fewer per day for 2 weeks to guarantee that you get into ketosis.
After that, you can add small amounts of carbs back to your diet very gradually, as long as you maintain ketosis.
Each person will potentially have a different carb intake limit to reach and maintain ketosis, depending on the total number of calories they eat and their daily activity levels. Generally, eating 5–10% of total calories from carbs will produce ketosis.
These carb and ketone ranges are advisedTrusted Source for people who want to get into ketosis to promote weight loss, manage their blood sugar levels, or reduce their heart disease risk factors.
Ketogenic diets used in epilepsy management and as experimental cancer therapy may also restrict carbsTrusted Source. However, anyone using the diet for therapeutic purposes should do so only under the supervision of a medical professional.
2. Include coconut oil in your diet
Eating coconut oil can help you get into ketosis.
Importantly, not all commercial coconut oil products you can buy in stores have the same content and health benefits.
Generally, coconut oil contains fats called medium-chain triglycerides (MCTs).
Unlike most fats, MCTs are rapidly absorbed and taken directly to your liver, where they can be used immediately for energy or converted into ketones.
Consuming coconut oil and these MCTs may be one of the best ways to increase ketone levels in people with Alzheimer’s disease and other nervous system disorders.
Although coconut oil contains four types of MCTs, around 50% of its fat comes from the kind known as lauric acid.
Some research suggests that fat sources with a higher percentage of lauric acid may produce a more sustained level of ketosis. This is because it’s metabolized more gradually than other MCTs.
MCTs have been used to induce ketosis in children who have epilepsy. In a high MCT diet, ketosis occurs without restricting carbs as drastically as in the classic ketogenic diet.
Other researchTrusted Source has found that a high MCT diet containing around 20% of calories from carbs produces effects similar to those of the classic ketogenic diet, which provides fewer than 5% of calories from carbs.
When adding coconut oil to your diet, it’s a good idea to do so slowly to minimize possible digestive side effects such as stomach cramping and diarrhea.
3. Ramp up your physical activity
Being more physically active each day can help youTrusted Source get into and stay in ketosis. It may also be beneficial for some types of athletic performance.
When you exercise, you deplete your body’s glycogen stores. These are normally replenished when you eat carbs, which are broken down into glucose. The glucose that isn’t needed immediately is stored as glycogen.
However, if you minimize your carb intake, your glycogen stores remain low. In response, your liver increases its production of ketones, which can be used as an alternative fuel source for your muscles.
Working out in a fasted state has been shownTrusted Source to drive up ketone levels.
But. keep in mind that although exercise increases ketone production, it may take 1–4 weeks for your body to adapt to using ketones and fatty acids as primary fuel sources. During this time, your physical performance may be temporarily reduced.
4. Increase your healthy fat intake
Consuming plenty of healthy fats can boost your ketone levels and help you reach ketosis.
Indeed, a very low carb ketogenic diet not only minimizes carbs but also calls for a high fat intake.
Ketogenic diets for weight loss, exercise performance, and metabolic health usually provide 55–60%Trusted Source of calories from fat.
The classic ketogenic diet used for epilepsy is even higher in fat. Typically, 85–90%Trusted Source of calories come from fat.
However, extremely high fat intake doesn’t necessarily translate into higher ketone levels.
A 3-week studyTrusted Source from 2015 that included 11 healthy people compared the effects of fasting on breath ketone levels. Overall, ketone levels were found to be similar in people consuming 79% of calories from fat and people consuming 90% of calories from fat.
Because fat makes up such a large percentage of a ketogenic diet, it’s important to choose high quality fat sources.
Healthy fats include fatty fish, olive oil, and avocado oil. Many healthy, high fat foods are also very low in carbs.
However, consuming high fat foods can lead to side effects such as:
- constipation
- diarrhea
- fatigue
- abdominal pain
- vomiting
- gastroesophageal reflux disease (in some children)
If weight loss is your goal, it’s important to make sure you’re not consuming too many calories in total, as this can cause your weight loss to stall.
5. Try a short fast or a fat fast
Another way to get into ketosis is to go without eating for several hours.
In fact, many people go into mild ketosis between dinner and breakfast.
Children with epilepsy traditionally fasted for 12–48 hours before they started a ketogenic diet. This approach often required supervision in a hospital.
Nonfasting protocols are more commonplace now. However, fasting can help ensure that some children get into ketosis quickly so that seizures can be reduced sooner.
Intermittent fasting, a dietary approach that involves regular short-term fasts, may also induce ketosis.
6. Maintain adequate protein intake
Getting into ketosis requires a protein intake that’s adequate but not excessive.
The classic ketogenic diet used in people with epilepsy restricts both carbs and protein to maximize ketone levels.
The same diet may be beneficial for people with cancer, as it may limit tumor growth.
However, for most people, drastically cutting protein intake to increase ketone production isn’t a healthy practice.
First, it’s important to consume enough protein to supply your liver with amino acids that can be used for gluconeogenesis, or making glucose.
In this process, your liver provides glucose for the few cells and organs in your body that can’t use ketones as fuel, such as your red blood cells and portions of your kidneys and brain.
Second, protein intake should be high enough to maintain muscle mass when carb intake is low, especially during weight loss.
Although losing weight typically results in the loss of both muscle and fat, consuming enough protein on a very low carb diet can help preserve muscle mass.
Several studies have shown that the preservation of muscle mass and physical performance is maximized when protein intake is in the range of 0.55–0.77 grams per pound (g/lb), or 1.2–1.7 grams per kilogram (g/kg), of lean mass.
A daily protein intake of 0.45–0.68 g/lb (1–1.5 g/kg) will help you maintain lean mass while losing weight.
To calculate your protein needs on a ketogenic diet, multiply your ideal body weight in pounds by 0.55–0.77 (1.2–1.7 in kilograms). For example, if your ideal body weight is 130 lb (59 kg), your protein intake should be 71–100 g.
7. Test ketone levels and adjust your diet as needed
As with many things in nutrition, reaching and maintaining a state of ketosis is highly individualized.
Therefore, it can be helpful to test your ketone levels to ensure you’re achieving your goals.
The three types of ketones — acetone, acetoacetate, and beta-hydroxybutyrate — can be measured in your breath, urine, and blood, respectively. Using one or more of these methods to test ketone levels can help you determine whether you need to make any adjustments to get into ketosis.
Acetone and the breath test
Acetone is found in your breath, and studies have confirmed that testing acetone breath levels is a reliable way to monitor ketosis in people following ketogenic diets.
The Ketonix meter measures acetone in your breath. After breathing into the meter, a color flashes to indicate whether you’re in ketosis and how high your levels are.
Acetoacetate and the urine tests
The ketone measured in urine is acetoacetate. Ketone urine strips are dipped into urine and turn various shades of pink or purple depending on the level of ketones present. A darker color reflects higher ketone levels.
Ketone urine strips are easy to use and fairly inexpensive. Although their accuracy in long-term use has been questioned, they should initially confirm that you’re in ketosis.
A small 2016 studyTrusted Source found that, in people on a ketogenic diet, urinary ketones tend to be highest in the early morning and after dinner.
Beta-hydroxybutyrate and the blood test
Lastly, ketones can be measured with a blood ketone meter. It works similarly to a glucose meter — you place a small drop of blood on a strip and insert it into the meter.
It measures the amount of beta-hydroxybutyrate in your blood, and this has been found to be a valid indicator of ketosis levels.
The disadvantage of measuring blood ketones is that the strips are very expensive.
Shop for ketone strips and blood test strips online.
Is Ketosis Safe and Does It Have Side Effects?
Because the keto diet is a low-carb diet, your body may enter ketosis naturally. Symptoms may be similar to that of the flu. But you may be wondering if ketosis is safe for everyone.
A ketogenic diet induces a state called ketosis. This is different from ketoacidosis, a serious condition that can happen when a person is unable to manage diabetes.
Ketosis is a natural metabolic state that may have benefits for weight loss (1Trusted Source, 2Trusted Source).
It may also have therapeutic effects for people with epilepsy, type 2 diabetes, and other chronic conditions (3Trusted Source, 4Trusted Source, 5Trusted Source, 6Trusted Source).
Ketosis is likely safe for most people, especially if they follow it with a doctor’s supervision.
However, it can have some negative effects, especially at the start. It’s also unclear how a ketogenic diet may affect the body long term (7Trusted Source).
How to minimize potential side effects
Here’s how to minimize the potential side effects of ketosis:
- Drink plenty of water. Consume at least 68 ounces (2 liters) of water a day. A significant amount of weight lost in ketosis is water, especially in the beginning.
- Get enough salt. The body excretes sodium in large amounts when carb intake is low. Ask your doctor if you should be adding salt to your food.
- Increase mineral intake. Foods high in magnesium and potassium may help relieve leg cramps.
- Avoid intense exercise. Stick to moderate levels of exercise in the first week or two.
- Try a low carb diet first. This might help you reduce your carbs to a moderate amount before moving onto a ketogenic (very low carb) diet.
- Eat fiber. A low carb diet is not a no-carb one. Ketosis typically starts when your carb intake is less than 50 grams a day. Eat fiber-rich foods like nuts, seeds, berries, and low carb veggies (7Trusted Source).
Summary: There are a few ways to minimize the negative symptoms of ketosis. These include drinking enough water and eating foods rich in fiber and minerals.
The low carb/keto flu
In the beginning of ketosis, you may experience a range of negative symptoms.
People often call these the “low carb flu” or “keto flu” because they resemble symptoms of the flu.
These may include:
- headache
- fatigue
- brain fog
- increased hunger
- poor sleep
- nausea
- decreased physical performance (8Trusted Source)
These issues may discourage people from continuing to follow a ketogenic diet before they start noticing the benefits.
However, the “low carb flu” is usually over within a few days.
Summary: The “low carb flu” or “keto flu” is a set of symptoms that can occur in the initial stages of ketosis. While it may cause some people to discontinue the diet, it’s usually over in a short amount of time.
Bad breath is also common
One of the more common side effects of ketosis is bad breath, often described as fruity and slightly sweet.
It’s caused by acetone, a ketone that’s a byproduct of fat metabolism.
Blood acetone levels rise during ketosis, and your body gets rid of some of it via your breath (9Trusted Source).
Occasionally, sweat and urine can also start to smell like acetone.
Acetone has a distinctive smell — it’s the chemical that gives nail polish remover its pungent odor.
For most people, this unusual-smelling breath will go away within a few weeks.
Summary: In ketosis, your breath, sweat, and urine may smell like acetone. This ketone is produced by the liver from fat and increases on a ketogenic diet.
Ketosis is healthy and safe, but is not suitable for everyone
A ketogenic diet may benefit some people, such as those with obesity or type 2 diabetes and children with epilepsy.
However, it can cause some side effects, including the “low carb flu,” leg cramps, bad breath, and digestive issues, especially in the first few days or weeks.
Experts also note that, while the diet can help you lose weight in the short term, the weight can return when you stop the diet. Many people don’t manage to stick with the diet (7Trusted Source).
Finally, a keto diet may not suit everyone. Some people experience significant benefits, while others feel and perform better on a higher carb diet.
People who are thinking of starting a keto diet should first talk to a healthcare provider who can help them decide if it’s a good option for them.
A medical professional can also help you follow the diet safely to minimize the risk of adverse effects.
Summary: A keto diet may be safe and helpful for some people, but you should check with your doctor before starting this diet.
