The ketogenic diet, which is a form of a low-carb diet, is currently on the rise as more people are recognizing its benefits for their health and fitness goals. But you might still be wondering, “what is the ketogenic diet all about, and can it work for me?” And that’s what we’re here to cover.
You can use this page as your comprehensive guide for everything you need to know about the ketogenic diet, or “keto” diet, and how to get started today!
KETOGENIC DIET BASICS
Basically, the purpose of the ketogenic diet is to force the body into burning fats instead of carbohydrates. Those who follow it eat a diet that contains high amounts of fat, moderate amounts of protein, and low levels of carbohydrates.
Through this breakdown of macronutrients, you’re able to change how the body uses energy to produce some pretty awesome benefits. But to fully understand how it works, it’s important to have a grasp on exactly how the body uses energy in the first place.
FAT FOR ENERGY VS CARBS FOR ENERGY
Normally, when you eat a diet rich in carbohydrates, your body converts the carbs to glucose for energy and makes insulin to transport the glucose into your bloodstream. Glucose is the “preferred” energy source of the body, so if it’s is present, the body will turn to it first.
When you lower your carbohydrate intake through a ketogenic diet, your body doesn’t have that same amount of carbs for fuel. Without prior knowledge, this might seem like a bad thing, but it actually produces remarkable results — because this sends your body into a state known as ketosis, which is the basis of a ketogenic diet.
Ketosis happens when the body turns to fat, instead of carbs, for fuel. Specifically, the liver converts the fatty acids in your body into ketone bodies, or ketones, to be used for energy. So when you overload the body with fats as the main energy source, it adapts and becomes “keto-adaptive,” or more efficient at burning fat!
The process of ketosis is a natural survival function of the body that helps it adapt when there’s not much food available. Similarly, the ketogenic diet focuses on “starving” the body of carbohydrates to facilitate ketosis and burn fat while also provide the body will great nutrition.
TYPES OF KETOGENIC DIETS
There are three types of ketogenic diets, although not all are suited for most people. The difference in each is fully dependent on carb intake:
The Standard Ketogenic Diet (SKD):
most common and recommended version of the diet where you stay within 20-50 grams of net carbs per day and focus on moderate protein intake and high fat intake.
Targeted Ketogenic Diet (TKD):
involves eating around 25-50 grams of net carbs or less around 30 minutes to an hour before exercise.
Cyclical Ketogenic Diet (CKD):
involves higher-carb periods where you eat a low-carb, ketogenic diet for several days followed by a couple days eating high-carb.
High-Protein Ketogenic Diet:
very close to a SKD, but with additional amounts of protein.
It’s important to note that out of each variation, the SKD is the most researched and best for the majority of people, so that’s what we’ll mostly be referring to in this article.
LOW CARB DIETS VS KETOGENIC DIETS
The keto diet often gets lumped in with any type of low-carb diet, but there are differences that should be noted. Some low-carb diets are not ketogenic, and the biggest difference is the level of carbohydrate intake.
For example, a low-carb diet might involve a moderate decrease in carbohydrates but not a large enough decrease to send you into ketosis. For example, the more modern version of Atkins often involves people adding in more carbs over time, which may be too much to go into ketosis or stay in ketosis for long periods of time.
HOW TO KETO? MODERATE PROTEIN AND HIGH FAT
Another difference between some low-carb diets and the keto diet is the amount of protein eaten. Those on the standard ketogenic diet, as described above, eat only a moderate amount of protein, which is less than what’s called for during other low-carb diets. This is because the body can also break down protein for glucose (known as gluconeogenesis) and prevent the body from reaching full ketosis.
The goal is to eat enough protein to main muscle mass and have your body turn to fat stores for energy.
Also, when the body goes through gluconeogenesis and starts using protein for fuel, it can raise your blood sugar and insulin levels — and these higher levels of insulin can affect the production of ketones.
On the other hand, fats have little, if any, effect on your blood sugar and insulin. And again, eating more fats prevents the body from pulling from your lean muscle mass, which is important for a lean, healthy body.
MACRONUTRIENTS ON A KETOGENIC DIET
The general breakdown of a keto diet looks like this:
- high in fat
- moderate in protein
- and low in carb
It’s important to note, as you’ll see, that the ketogenic diet is not a high-protein diet. As we explained above, the categorization of a diet as ketogenic depends on the amount of protein and carbs eaten each day.
Here are the general percentages of nutrients on a ketogenic diet:
- Calories from carbs: 5-10%
- Calories from protein: 20-25%
- Calories from fat: 70-80% (sometimes more for certain people)
This is a general range, although numbers can vary slightly depending on each person’s needs and goals on the diet.
For most people, a range of 20-50 grams of carbohydrate intake per day is ideal for the keto diet. Some people can go as high as 100 grams per day to stay in ketosis, but the majority should stay in the initial range.
Some factors to take into account when determining your protein needs of the keto diet include:
- Lean body mass
- Ideal body weight
- Activity level
As mentioned before, too much protein intake can impede ketosis. To avoid the breakdown of protein instead of fat for glucose, you’ll want to avoid eating more than 1.5 to 2 grams per kilogram of lean body mass.
After you’ve calculated your carb and protein requirements, the remaining caloric intake will come from fats in the diet.
Counting of specific calories are generally not required on a ketogenic diet (since a diet high in satisfying fat rarely leads to overeating), but you do want to make sure you’re keeping general track of your macronutrient percentages versus how much you eat, since big changes in calorie intake can affect those percentages.
Don’t forget that the type of fat is important when eating a ketogenic diet. Be cautious about consuming a lot of oils, as they are usually high in omega-6 fatty acids, which are inflammatory in large amounts.
Instead, opt for fat sources that are high in monounsaturated and saturated fats and low in polyunsaturated fats. Here are some common fat sources on the ketogenic diet:
- MCT oil or coconut oil (as they can be easily converted to ketones)
- Butter (look for sources from cows that were grass-fed)
- Olive oils
- High oleic sunflower and safflower oils
- Full-fat cheese and other dairy products
- Full plant-based fats like avocado
To break it down even further, here’s a general guide for what to eat and avoid on a ketogenic diet:
RECOMMENDED FOODS FOR KETOGENIC DIET
- Meats including: beef, chicken and other poultry, pork, lamb, goat, turkey, veal, and fish sources like salmon, sardines, catfish, tuna, trout, etc.
- Fats and oils including: nuts and seeds (whole or as butters), oils like olive oil, sesame oil, or high oleic sunflower and safflower oils, ghee, and grass-fed butter.
- Eggs(preferably free-range).
- Dairy products including: cheeses, sour cream, yogurt, and heavy creams.
- Low-carb vegetables including: spinach, kale, broccoli, Brussels sprouts, asparagus, peppers, and onions.
- ONLY lower-sugar fruits including: blueberries, strawberries, raspberries, and avocados (and only in small amounts).
- Herbs and spices: as long as they have no added sugars.
FOOD TO ELIMINATE ON KETOGENIC DIET
- Beans and legumes including: kidney beans, chickpeas, black beans, lentils, and green peas.
- Grains including: whole grains and breads and pastas made from grains like oats, wheat, barley, rice, rye, and corn.
- Fruits besides small portions of berries.
- Starches including: potatoes, sweet potatoes, parsnips, and carrots.
- Low-fat diet products that are packaged and processed.
- Sugar-laden products including: smoothies, sodas, fruit juices, ice cream, cookies, cakes, and candies.
- Unhealthy oils including: mayonnaise products and processed vegetable oils
- Alcohols, as they can take you out of ketosis from the high carb content.
- Artificial sweeteners, which can sometimes affect blood sugar levels.
- Condiments that contain added sugar or unhealthy oils.
HEALTH BENEFITS ON A KETOGENIC DIET
Since a low-carb diet has been shown to have greater effects on weight loss than other diets, it’s a good option for obese people who are looking to reduce their weight, blood pressure, and cholesterol over a short period of time. Plus, a ketogenic diet may also help improve insulin resistance and lower glucose levels.
Ketogenic diets may also be helpful for:
- Eliminating diseases related to blood sugar like type II diabetes
Reducing risk factors for heart disease, including improvement in:
- HDL cholesterol
- LDL cholesterol (related to plaque in the arteries)
- Lessening skin inflammation and lesions in those with acne
- Less hunger, since fat is more dense and satisfying, helping you feel full longer
- Preventing seizure in people, especially children, with epilepsy
HOW TO WORK OUT ON A KETOGENIC DIET
The ketogenic diet may also be helpful in improving endurance levels for athletes. That being said, for some people it might first take some time to adjust to the diet change.
If there are any limitations in fitness performance at the beginning of a ketogenic diet, it’s just because the body is still adapting to the switch from carbohydrates to fat for its main energy source. Studies have shown thataerobic endurance overall is not decreased with a ketogenic diet.
Bodybuilders and serious athletes might also consider try the targeted ketogenic diet or cyclical ketogenic diet (as described above) if they find themselves needing a further boost in performance.
Protein Intake and Muscle
If you’re goal is to continue putting on muscle mass, be sure you’re eating 1-1.2 grams of protein for pound of body mass. Also note that those eating a ketogenic diet won’t be putting on as much body fat as someone eating carbs, so it can look like you aren’t gaining muscle as fast, but that’s not the case.
HOW TO KNOW WHEN YOU’RE IN KETOSIS
Ketosis can be a gray area, as there are varying degrees of it. In general, it can often take around 1-3 days to reach full ketosis.
The best way to monitor your ketone levels is through testing, which you can do right from your home own.
When you eat a ketogenic diet, excess ketones spill over into several areas of the body, giving you a few different ways to monitor your ketone levels:
- In your urine with a urine strip
- In the blood with a glucose meter
- On the breath with a breathe meter
Each have their advantages and disadvantages, but measuring ketones in the blood is often the most effective. Urine testing can be less accurate, but it’s also the most affordable and simple option when you’re just starting with a keto diet.
For more information on checking your ketone levels, see this article.
THE KETOGENIC DIET VS HIGH CARB DIET
Due to the popular-yet-false message that fat is bad and harmful being spread through the nutrition community in the last 30 years, many people are afraid of eating too much fat, especially saturated. That’s why high-carb and/or low-fat diets continue to be a popular form of diet and weight loss method.
Obviously, a ketogenic diet flies in the face of this philosophy and turns it on its head for several reasons:
- A diet that is high in carbs, especially when they are refined and processed carbs from traditional low-fat diet products, can increase insulin and blood sugar levels and promote inflammation in the body.
- A very low-carb diet can help reduce inflammation far better than a low-fat diet.
- Saturated fat is not shown to be harmful within the context of a low-carb diet, as it helps simultaneously increase the amount of HDL (good) cholesterol while decreasing total triglyceride levels, and these two factors are what we look at most for determining heart disease.
- A ketogenic diet is shown to be more effective for health and
cholesterol levels than a low-fat diet.
- Also, a high-carb diet AND high-fat diet is even worse. Since it involves eating lots of carbohydrates, it’s easy for your body to immediately produce glucose and leave excess fats for immediate storage.
POSSIBLE SIDE EFFECTS OF KETOGENIC DIET
Some people may experience certain short-term side effects within the first one to two weeks of starting a ketogenic diet. These are temporary and could include:
- Mental fogginess
- Flu-like symptoms
- Mild irritability or fatigue
Note that these only occur as your body and brain are adjusting to the sudden removal of carbohydrates from the diet, and they should go away completely once your body has adapted to the low carb intake. They are also fairly easy to alleviate until then.
Be sure to drink plenty of water during this time to easy any possible side effects. Increasing salt intake can also help minimize symptoms, since less carbs can cause your body to lose water and this will help you replenish and retain it.
Another option is to lower your carb intake more gradually until you reach ketosis if you feel your body needs a longer adjustment period.
KETOSIS VS KETOACIDOSIS
Those with diabetes should be aware of diabetic ketoacidosis, which is a dangerous state that can be a risk for diabetics that don’t take enough insulin, get sick or hurt, or aren’t drinking enough fluids. Other causes of ketoacidosis could include alcoholism, an overactive thyroid, or true starvation.
With ketoacidosis, ketones levels reach an extremely high level that can turn the blood acidic. This is not the same as safe and healthy ketosis that occurs from eating lowcarb with a ketogenic diet.
As you can see, there are many health and nutritional benefits of adopting a ketogenic diet. If you’re interested in trying it for yourself, be sure to listen to your body and follow the guidelines carefully to ensure a healthy and successful keto experience.