The ketogenic diet is a very low-carb, high-fat diet that shares many similarities with the Atkins and low-carb diets.
It involves drastically reducing carbohydrate intake and replacing it with fat. This reduction in carbs puts your body into a metabolic state called ketosis.
When this happens, your body becomes incredibly efficient at burning fat for energy. It also turns fat into ketones in the liver, which can supply energy for the brain.
Ketogenic diets can cause massive reductions in blood sugar and insulin levels. This, along with the increased ketones, can have numerous health benefits
Different Types of Ketogenic Diets
There are numerous versions of the ketogenic diet, including:
Standard ketogenic diet (SKD): This is a very low-carb, moderate-protein and high-fat diet. It typically contains 75% fat, 20% protein and only 5% carbs. (Source)
Cyclical ketogenic diet (CKD): This diet involves periods of higher-carb refeeds, such as 5 ketogenic days followed by 2 high-carb days.
Targeted ketogenic diet (TKD): This diet allows you to add carbs around workouts.
High-protein ketogenic diet: This is similar to a standard ketogenic diet, but includes more protein. The ratio varies but is often 60% fat, 35% protein and 5% carbs.
However, only the standard and the high-protein ketogenic diets have been studied extensively. Cyclical or targeted ketogenic diets are more advanced methods and primarily used by bodybuilders and athletes.
The information in this blog-post mostly applies to the standard ketogenic diet (SKD). Having said that, many of the same principles also apply to the other versions of the keto diet.
In fact, research shows that the ketogenic diet is far superior to the often recommended low-fat diet Source
What’s more, the diet is so filling that you can lose weight without counting calories or tracking your food intake.
Furthermore one study found that people on a ketogenic diet lost two and a half times more weight than those on a calorie-restricted low-fat diet. Triglyceride and HDL cholesterol levels also improved. If you'd like to read more on that, here is the link.
There are several reasons why a ketogenic diet is superior to a low-fat diet, including the increased protein intake, which provides.
The increased ketones, lower blood sugar levels and improved insulin sensitivity may also play a key role.
Reasons Behind The Weight Loss
A “keto” or “ketogenic” diet is so called because it causes your body to produce small fuel molecules called “ketones.”
There are three different ketones, or “ketone bodies” used as fuel by your body.
Ketones are an alternative fuel source for your body that can be used when blood sugar (glucose) is in short supply.
When you eat very few carbs or very few calories, your liver produces ketones from fat. These ketones then serve as a fuel source throughout the body, especially for the brain.
Brain-food
The brain is a very hungry organ that consumes a lot of energy all day long. It can’t run on fat directly furthermore the brain can only run on glucose or ketones.
“As an energy-consumer, the brain is the most expensive organ we carry around with us,” says Dr. Marcus Raichle, a distinguished professor of medicine at Washington University School of Medicine in St. Louis. While the brain represents just 2% of a person’s total body weight, it accounts for 20% of the body’s energy use, Raichle’s research has found.
This could be a bonus for weight loss, if your hungry brain burns fat for you.
Another note: ketosis is why the old idea that “the brain needs carbohydrates” is wrong – the brain requires limited amounts of glucose even in ketosis, but the body can create that glucose from protein and fat in a process called gluconeogenesis.
On a ketogenic diet, your entire body switches its fuel supply to run mostly on fat, burning fat 24-7. When insulin levels drop very low, fat burning can increase dramatically. It becomes easier to access your fat stores to burn them off.
In a large majority of high-quality trials, low-carb diets have been found to be more effective for weight loss than other diets:
Low-carb diets might increase metabolism – potentially increasing fat burning by between 200 and 500 calories per day. As mentioned above.
When the body produces ketones, it enters a metabolic state called ketosis. The fastest way to get there is by fasting, not eating anything, however it is highly unlikely that we can all fast forever and maintain our current standard of life.
Starvation Ketosis
The ketosis experienced after a longer period of fasting is called starvation ketosis. But since starvation is neither healthy nor sustainable, we focus more on nutritional ketosis. However, intermittent fasting may have a role as an adjunct to diet for health gains and weight loss.
A keto diet, on the other hand, also results in ketosis and can be eaten indefinitely. It has many of the benefits of fasting – including weight loss – without having to fast long term.
The ketosis experienced on a ketogenic diet is often called nutritional ketosis. This seems to be sustainable long term.
Studies have demonstrated that ketosis can be maintained for years; for instance, in children treated with a ketogenic diet for epilepsy, and for at least a year or two when treating obesity or type 2 diabetes.
It may even be possible to stay on a ketogenic diet indefinitely. There is no obvious or proven upper limit for how long nutritional ketosis can be maintained. This is based on clinical experience of low-carb practitioners.
Ketogenic Diets for Diabetes and Prediabetes
Diabetes is characterized by changes in metabolism, high blood sugar and impaired insulin function.
The ketogenic diet can help you lose excess fat, which is closely linked to type 2 diabetes, pre-diabetes and metabolic syndrome. Source
One study found that the ketogenic diet improved insulin sensitivity by a whopping 75%.
Another study in people with type 2 diabetes found that 7 of the 21 participants were able to stop using their diabetes medications.
Other Possible Health Benefits of Keto
The ketogenic diet actually originated as a tool for treating neurological diseases such as epilepsy.
Studies have now shown that the diet can have benefits for a wide variety of different health conditions:
Heart disease: The ketogenic diet can improve risk factors like body fat, HDL cholesterol levels, blood pressure and blood sugar.
Cancer: The diet is currently being used to treat several types of cancer and slow tumor growth Results on these studies are not expected to come in for quite some time tho.
Alzheimer’s disease: The keto diet may reduce symptoms of Alzheimer’s disease and slow its progression.
Epilepsy: Research has shown that the ketogenic diet can cause massive reductions in seizures in epileptic children.
Parkinson’s disease: One study found that the diet helped improve symptoms of Parkinson’s disease.
Acne: Lower insulin levels and eating less sugar or processed foods may help improve acne.
However, keep in mind that research into many of these areas is far from conclusive. It takes many years to conduct reliable studies.
Keto Friendly Foods to Eat
You should base the majority of your meals around these foods:
Meat: Red meat, steak, ham, sausage, bacon, chicken and turkey.
Fatty fish: Such as salmon, trout or tuna.
Eggs: Look for pastured or omega-3 whole eggs.
Butter and cream: Look for grass-fed butter.
Cheese: Unprocessed cheese (cheddar, goat or mozzarella).
Nuts and seeds: Almonds, walnuts, flax seeds, pumpkin seeds, chia seeds, etc.
Low-carb veggies: Most green veggies, tomatoes, onions, peppers, etc.
Condiments: You can use salt, pepper and various healthy spiced oils, herbs and spices.
It is best to base your diet mostly on whole, single-ingredient foods.
Healthy Keto Snacks
In case you get hungry between meals, here are some healthy, keto-approved snacks:
Fatty meat or fish
Cheese
A handful of nuts or seeds
Cheese with olives
1–2 hard-boiled eggs
90% dark chocolate
A low-carb milkshake with almond milk, cocoa powder and nut butter
Strawberries and cream
Celery with salsa and guacamole
Foods to Avoid when on Keto
Any food that is high in carbs should be limited or avoided.
Here is a list of foods that need to be reduced or eliminated on a ketogenic diet:
Sugary foods: Soda, fruit juice, smoothies, cake, ice cream, candy, etc.
Grains or starches: Wheat-based products, rice, pasta, cereal, etc.
Fruit: All fruit, except small portions of berries like strawberries.
Beans or legumes: Peas, kidney beans, lentils, chickpeas, etc.
Root vegetables and tubers: Potatoes, sweet potatoes, carrots, parsnips, etc.
Low-fat or diet products: These are highly processed and often high in carbs.
Some condiments or sauces: These often contain sugar and unhealthy fat.
Unhealthy fats: Limit your intake of processed vegetable oils, store bought mayonnaise, salad dressings etc.
Alcohol: Due to their carb content, many alcoholic beverages can throw you out of ketosis.
Sugar-free diet foods: These are often high in sugar alcohols, which can affect ketone levels in some cases. These foods also tend to be highly processed - avoid whenever possible.
Tips for Eating Out on a Ketogenic Diet
It is not very hard to make most restaurant meals keto-friendly when eating out.
Most restaurants offer some kind of meat or fish-based dish. Order this, and replace any high-carb food with extra vegetables.
Egg-based meals are also a great option, such as an omelet or eggs and bacon.
Another favoriteof ours is a bun-less burger. You could also swap the fries for vegetables instead. Add extra avocado, cheese, bacon or eggs.
At Mexican restaurants, you can enjoy any type of meat with extra cheese, guacamole, salsa and sour cream.
For dessert, ask for a mixed cheese board or berries with cream. Also coconut-cream chocolate deserts are more and more often found on bistro and restaurant menus.
Side Effects and How to Minimize Them
Although the ketogenic diet is safe for healthy people, there may be some initial side effects while your body adapts.
This is often referred to as the keto flu and is usually over within a few days.
Keto flu includes poor energy and mental function, increased hunger, sleep issues, nausea, digestive discomfort and decreased exercise performance.
To minimize this, you can try a regular low-carb diet for the first few weeks. This may teach your body to burn more fat before you completely eliminate carbs.
A ketogenic diet can also change the water and mineral balance of your body, so adding extra salt to your meals or taking mineral supplements can help.
At least in the beginning, it is important to eat until you’re full and avoid restricting calories too much. Usually, a ketogenic diet causes weight loss without intentional calorie restriction.
A Ketogenic Diet Is Not for Everyone
A ketogenic diet can be great for people who are overweight, diabetic or looking to improve their metabolic health.
It may be less suitable for elite athletes or those wishing to add large amounts of muscle or weight.
And, as with any diet, it will only work if you are consistent and stick with it in the long term.
For more details about pros and cons in different situations, check with your doctor, physician or nutritionist. Furthermore you should also look into scientific papers exploring the potential contradictions of being on any sort of keto diet.
Disclaimer
Disclaimer: While the ketogenic diet has many proven benefits, it’s still controversial and not fully scientifically explored. The main potential danger regards medications for various conditions, e.g. for diabetes, where doses may need to be adapted. Discuss any changes in medication and relevant lifestyle changes with your doctor.