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The Ultimate Keto Diet Guide


calendar-iconJuly 15, 2020

Fat Loss


Nutrition Plans

There are plenty of diet trends out there on the Internet these days, but which ones really work? Which one will help me lose weight and allow me to look my best? 

One of the most well-known diets is the keto, or ketogenic diet. There’s a chance you’ve heard about it somewhere else before, as it has become quite popular among celebrities. 

If you’re curious to learn more about what the keto diet is and how it works, then this guide is for you. We will go over the basics of the keto diet, as well as some of the benefits and risks that come with it. We will also discuss how it can be used in combination with intermittent fasting.

So is this really a healthy diet? Is it effective as everyone says?

First, let’s talk about what exactly the keto diet is.

What Exactly Is the Keto Diet?

According to Healthline, the keto diet is “a very low-carb, high-fat diet that shares many similarities with the Atkins and low-carb diets”. By lowering the amount of carbohydrates you consume, your body must use fat for energy instead, which puts your body into a state called ketosis. This will be explained in more detail in the next section. 

There are many different variations of the ketogenic diet, although this article will focus primarily on the standard keto diet. Some variations of the keto diet include: 

  • Standard ketogenic diet (SKD) – A “high fat, adequate protein, low carbohydrate diet”, according to PubMed Central. This diet usually allocates your daily food intake to 75% fats, 20% proteins and only 5% carbs.
  • Cyclical ketogenic diet (CKD) – This variation of the keto diet typically revolves around a schedule where you allow yourself to have a high amount of carbohydrates on certain days, while only having a very small amount on the other days. For example, you could limit yourself to only 25-30 grams of carbs on Monday, Tuesday, Wednesday, Thursday, and Saturday, and then let yourself consume your typical amount of carbs on Friday and Sunday.
  • Targeted ketogenic diet (TKD) – The targeted ketogenic diet allows you to eat more carbs before you are going to workout, so that you have more energy and train better. For example, if you are about to go to the gym and try to get a new personal best on your deadlift, you would eat some extra carbs (like pasta or fruit) for an extra burst of energy. You are still limiting your carb intake for the rest of the day, but consuming a few more around your workouts will help you improve your athletic performance
  • High-protein ketogenic diet – This diet is similar to the standard keto diet, but lets you have more protein. Typically the ratio is 60% fat, 35% protein and 5% carbs. More protein is essential for building and retaining muscle, so bodybuilders and athletes may prefer this variation of the keto diet.

How exactly does the ketogenic diet work though, and what is ketosis? The next section will take you back to the basics of nutrition and explain why the keto diet is effective.

How Does the Keto Diet Work?

By reducing your carbohydrate intake, you are forcing your body to utilize fats for fuel. This puts your body into a metabolic state called ketosis. “Ketosis is a metabolic state in which your body uses fat and ketones rather than glucose (sugar) as its main fuel source”, according to Diet Doctor

In other words, instead of glucose being produced by your liver and used for energy, ketones become the body’s primary energy source. Ketones are small molecules that use fat, both from your own body and from food, in order to keep your brain energized. As your body starts to mainly run on ketones instead of glucose, you may see that your weight starts to decrease. Keep in mind that weight loss does not rely solely on ketones or ketosis, and that you can definitely gain weight while in ketosis if you don’t watch what you eat. To put it simply, the only real way to lose weight is to burn more calories than you take in.

Forcing your body to run on ketones and fats, instead of carbohydrates, is quite a shock for your metabolic system. The body is not normally meant to use fats for fuel, so the keto diet can be seen as a sort of metabolic reset. As we mention in our foundational nutrition guide, “carbohydrates (commonly referred to as carbs) are the main source of energy for you during everyday life and exercise”. In other words, the keto diet makes your body get rid of its main energy source, and forces it to adapt to a new one. This can help promote fat loss as long as you eat the right foods and stay in a caloric deficit.

Our article later goes on to say that “fats not only serve as a critical source of energy for your body, but they also should be consumed in moderation”. So although fats should typically not be consumed in large amounts, the keto diet requires that you significantly increase your fats intake, so that you meet your caloric needs for the day. It may seem that this diet is risky and unpractical as of right now, since it is making you change your foundational eating habits and consume a large amount of fats. However, there are numerous benefits of the ketogenic diet that are definitely worth considering.

What Are Some of the Benefits of the Keto Diet?

There are many other benefits of the keto diet besides weight loss, according to Harvard Health Publishing, Healthline, and PubMed Central. Some of them include: 

  • Improved body fat, HDL cholesterol, and blood pressure – all factors that can lead to heart disease, according to PubMed Central
  • Improved blood sugar control in those with type 2 diabetes
  • Improved symptoms of Parkinson’s disease, according to this study
  • Massive reduction in seizures in children due to epilepsy – interestingly enough, this was the original purpose of the ketogenic diet. According to Harvard Health Publishing, “Despite the recent hype, a ketogenic diet is not something new. In medicine, we have been using it for almost 100 years to treat drug-resistant epilepsy, especially in children”.
  • Reduced symptoms and slowed progression of Alzheimer’s disease
  • Used to treat several different types of cancer, including brain cancer
  • Used to treat concussions and aid in recovery from brain injury 

You should remember that not everyone will have the exact same experience on the keto diet, and that you may not always see the benefits you desire. Be sure to think carefully and consult with your doctor before going on this diet.

What Foods Can You Eat on the Keto Diet?

The most important thing to remember when deciding what to eat on the keto diet is that you want to choose foods that are very low in both carbs and sugars. Although carbs and sugars give you energy, they also take your body out of ketosis and prevent you from losing weight. Here are some of the best keto diet foods, according to Diet Doctor and Healthline: 

  • Meat – unprocessed meats that are low in carbs; should be eaten in moderation since meat has a lot of protein. The goal is to consume a high amount of fats.
  • Fish and seafood – Fatty fish like salmon is especially good to eat on the keto diet; be sure to avoid fried and other breaded fish.
  • High-fat sauces
  • Vegetables such as cauliflower, cabbage, broccoli, and zucchini 
  • Butter
  • High-fat cheese 
  • Nuts (in moderation)
  • Berries (in moderation) – blueberries, raspberries, strawberries, etc.
  • Avocados
  • Healthy oils – extra virgin olive oil, coconut oil and avocado oil

So what types of foods should you stay away from if you are on a keto diet? Here are a few of the key ones: 

  • Sugary foods – soda, cookies, cake, ice cream, fruit juice, etc.; 
  • Starches – bread, french fries, rice, potatoes, legumes (beans and lentils), most whole grain products, etc. 
  • Fruit – except for berries
  • Alcohol – only for very special occasions 
  • Root vegetables, such as carrots or parsnips
  • Low-fat/diet products – often high in carbs 

Remember that you must choose your meals very carefully, as eating too many carbs will disrupt your body’s metabolism and take you out of ketosis. Make sure to check the labels on all your food items and see how many carbs they contain before eating them.

What are the Keto Diet Side Effects?

You might be wondering: is the keto diet safe? What are the side effects? As with any diet, there are a few risks that come with intermittent fasting that should be kept in mind. Here are some of them

  • “Keto flu” – It can be tough on your body when it has to switch from using glucose to ketones for energy, and it can cause you to feel like you have the flu. Some symptoms include dizziness, fatigue, insomnia, slow thinking, and cravings for certain foods. Therefore, it might be wise to slowly decrease your carb intake over the span of a few weeks, in order for these effects to not feel as severe.
  • Loss of salts – Salts and fluids can be depleted from your body as it uses up the last of its stored energy from glycogen (sugar), so be sure to keep yourself hydrated by drinking plenty of water.
  • Constipation – Your bowel habits might change because of your new diet, so be sure to drink plenty of water, and make sure you’re getting enough fiber.
  • Leg cramps – Not having enough salt (as mentioned above) can cause cramps in your legs, so once again, it is important to stay hydrated and consume a sufficient amount of salt. 
  • Bad breath – Commonly referred to as “keto breath”, this can result from ketones being released from your body, and can leave a metallic taste in your mouth. Make sure you practice good oral hygiene and chew gum if you wish, and the bad breath should disappear within a few weeks. 
  • Reduced physical performance – A lack of fluids and salts, as well as the change to burning fat for energy instead of sugar, can result in you not being able to perform as well athletically in the first few weeks. However, many elite athletes have seen an increase in endurance over time, and have found that potentially being able to burn fat mass for energy (instead of glucose) could vastly improve their physical performance.

As stated before, make sure to know the risks and consider them carefully before starting the keto diet (or any diet). Be sure to discuss any potential dangers with your doctor.

Combining the Keto Diet with Intermittent Fasting

The keto diet and intermittent fasting are two very popular health trends currently, and there are plenty of people who have wondered about combining the two. Does an intermittent fasting keto diet work though? Is it safe? 

According to Healthline, “Combining the ketogenic diet with intermittent fasting is likely safe for most people”. Most people without any pre-existing health conditions can definitely add intermittent fasting to their ketogenic diet, but they should only do so once they feel comfortable on a keto diet. 

There are certain groups, though, that should not attempt to do intermittent fasting along with a keto diet. Everyday Health says, “If you have chronic kidney disease, a history of eating disorders, are undergoing active cancer treatment, or are pregnant or breastfeeding, it’s unlikely you’re a good candidate for this combined diet plan. Even the individual diets (keto and IF) may not be recommended for these populations”.
Combining intermittent fasting and the keto diet can help speed up weight loss and fat burn by causing your body to use fat as its primary fuel source. However, doing the two methods together is not safe for everyone, so talk with your doctor before you consider trying this. In addition, to learn more about intermittent fasting, be sure to read our article “What is Intermittent Fasting, and Should You Try It?”.

Frequently Asked Questions

How long does it take to get into ketosis?

It depends on your age and your carb intake before you started the keto diet, according to the Diet Doctor. Younger people, as well as those who did not consume a lot of carbs before starting the diet,  generally get into ketosis faster, while those with insulin resistance can take longer. It can take anywhere from 1-2 days, up to a week or more. 

Can I take supplements on the keto diet?

Absolutely. Since the keto diet can leave you at a risk for nutritional deficiencies, taking supplements can help you stay healthy. According to Healthline, here are some of the most valuable supplements:

  • Magnesium – It may be hard to meet your magnesium nutritional needs on the keto diet, since most foods with a lot of magnesium also have a high amount of carbs. Therefore, certain magnesium supplements, like magnesium glycinate, magnesium gluconate and magnesium citrate, can help you get the amount you require each day. Foods like spinach, swiss chard, avocado and mackerel are all good sources of magnesium as well.
  • MCT Oil – Supplementing with MCT Oil has helped those on the keto diet because it increases their fat intake, leading them to produce more ketones and stay in ketosis longer. It may also cause you to lose more weight and feel full, making MCT oil very useful if you’re on this diet.
  • Omega-3 Fatty Acids – Omega-3 fatty acid supplements help to keep your nutrition in check while you’re on the keto diet, and improve your overall health. This study showed that “people following a ketogenic diet who supplemented with omega-3 fatty acids from krill oil experienced greater decreases in triglycerides, insulin and inflammatory markers than those who did not”. Eating more anchovies, sardines and salmons will increase your intake of omega-3 fatty acids.
  • Electrolyte Supplements – Starting the keto diet can result in your body losing a lot of water, as well as sodium, potassium and magnesium. This loss of important minerals may lead to symptoms of the keto flu, and impede your weight loss progress. Eating the right foods and taking electrolyte supplements, however, will leave you feeling energized and healthy. Healthline says, “Dark leafy greens, nuts, avocados and seeds are all keto-friendly foods that are high in both magnesium and potassium. Electrolyte supplements containing sodium, potassium and magnesium are available as well”.

Are there any sample low-carb recipes I can use?

Yes! Diet Doctor has an excellent sample meal plan for the first 14 days of your keto diet. There are plenty of great recipes and plans online that are low in carbs and very easy to prepare for yourself at home.

How much weight can I lose on the keto diet?

Again, that completely depends on a few different things, with the major one being whether or not you are in a caloric deficit. It does not matter if you are in ketosis or not; you will not lose much weight (if any) if you are consuming more calories than your body burns on a daily basis. Although you are very limited in what exactly you can eat, it does not matter if you overeat and do not do any exercise to stay in a caloric deficit. Meal portions and exercise are two of the key factors in determining how much weight you lose, whether or not you are on a special diet plan.

Another factor that can affect how much weight you lose is how long it takes your body to go into ketosis. According to Perfect Keto, some factors that can affect how much weight you lose (and how quickly you lose it) are your current health conditions, body composition, daily habits and your fat adaption period (how long your body takes to become accustomed to running on ketones). 

Typically, though, Perfect Keto says that you could lose anywhere from 2 to 10 pounds in your first week on the keto diet, most of it in the form of water weight. In the following weeks, it should drop down to about a pound or two per week, depending on your caloric deficit. As you get close to your goal weight, your weight loss may slow down even more. As long as you keep eating the right foods and getting plenty of exercise, though, the keto diet should stay consistent and effective for as long as you do it.


Here are some of the key points that were made about the keto diet in this article: 

  • The keto diet is a diet where you consume a very small amount of carbohydrates and a large amount of fats. This will force your body to use fats for energy instead of carbs, and will put you into a state of ketosis. In this state, your body burns fat as its main energy source, potentially leading you to lose weight at a much quicker rate. 
  • There are several variations of the keto diet that people use, but the most common one is the Standard Ketogenic Diet (SKD), which consists of low carbs, moderate proteins, and high fats.
  • Some of the foods you should eat include meat, fatty fish, eggs, and low-carb veggies, and some of the foods you should avoid are grains, fruits, sugary foods (like soda or fruit juice), beans and alcoholic beverages.
  • The keto diet has been proven to help you lose excess fat, improve insulin sensitivity in those with diabetes, and reduce your risk for heart disease. In addition, studies have shown that it can also be used to treat several types of cancer, Alzheimer’s disease, and epilepsy in children. 
  • There are a few negative side effects that can occur as your body adapts to the keto diet, such as lower energy levels, nausea, sleep issues, and increased hunger. Commonly referred to as the keto flu, these effects should last only a few days. The keto diet also reduces the rate at which you build muscle because you aren’t consuming a high amount of protein, so it may not be a suitable diet for bodybuilders or professional athletes.
  • A popular way of losing weight is to do a combination of both the keto diet and intermittent fasting. Although these two diets can be very effective when used together, they are very restrictive and can lead to serious nutritional deficiencies if taken too far. Therefore, it is important to build up to this slowly, after you have tried keto and intermittent fasting separately first.

For more valuable information on nutrition and other fitness topics, be sure to check out


Date Created: July 15, 2020

Last Updated: November 11, 2021

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