What's the Ketogenic Diet? 
A Complete Beginner's Guide to Keto

Keto Diet Cover Image

The keto diet has been gaining popularity over the past few years with dieters like celebrities and athletes praising it and the its benefits of quick weight loss and increased energy.

As the diet increases in popularity and more people look to it for weight loss, it is more important than ever to learn about this diet that has been around for nearly 100 years.

There is a lot of controversy among professionals regarding the ketogenic diet due to the general lack of research on its long-term effects. Regardless, more and more people are seeing success in being able to lose weight with keto compared to other diets. They claim that it is a quick and easy-to-follow diet compared to other diet and weight loss plans they have tried before.

What is the Keto Diet?

keto group of foods

​The ketogenic diet is a low-carb, high-fat diet that forces your body to use fat as its main source of energy instead of carbohydrates by eliminating nearly all carbs from your diet.

This diet switches your body into a metabolic state called ketosis and will start burning fat for energy instead of relying on the glucose from carbs.

When on the keto diet, you avoid carbs by cutting out processed foods such as sugar, bread, pasta, and other carbs. Instead, you eat more meats, fish, vegetables, and natural fats.

The ketogenic diet is very similar to Paleo and Atkins diets and is also gluten-free.

What Does “Keto” Mean?

letters of keto

Keto refers to ketogenic or the metabolic process of ketosis where your body uses fat to produce ketones for energy instead of carbs or blood sugar.

When your body is being fueled mostly by fat, it is in ketosis.

To do this, your liver breaks down fat into ketones when there is a lack of energy from carbs. Ketones are a fuel molecule that provides constant energy to your body. That means you burn fat while you are asleep!

Who SHOULD NOT Be Doing the Keto Diet?

If you have certain health conditions, such as type 2 diabetes or high blood pressure, you should consult a doctor before starting the keto diet.

insulin shot

The ketogenic diet can alter the effects of medication taken for type 2 diabetes [1] and high blood pressure, and potentially eliminates the need for medication completely.

Therefore, it is important for your doctor to adjust your medications as necessary. If your medication goes unadjusted, risk factors include being dangerously under or overmedicated.

If you are pregnant or breastfeeding, the keto diet may not be for you either.

Eating a strict low-carb diet while you are pregnant or breastfeeding can be dangerous and may not be able to provide enough nutrients to your baby. Moderate low-carb diets are recommended in the meantime.

DISCLAIMER: The ketogenic diet has proven to be very beneficial for most dieters, but it is still highly controversial in regards to its effect on dieters with certain conditions and those who are taking certain medications.

A doctor should always be consulted before any lifestyle changes such as starting the ketogenic diet.

How to Get Started on the Keto Diet

charts for nutrients intake

​The best way to get started on the keto diet is to start cutting carbs wherever possible.

The main goal of the diet is to eliminate almost all carbs from your diet and to include more healthy fats to trigger ketosis.

Once you start cutting out carbs, you can start to replace them with high fat or keto-friendly alternatives.

Knowing the basics of all of the foods allowed and not allowed on the ketogenic diet can help you make the right decisions and start experimenting with delicious ketogenic recipes. Reading nutrition labels thoroughly will be a big help, as well.

Here is a helpful guide on what to eat and not to eat on the ketogenic diet:

What to Eat on a Keto Diet

​Most whole foods, or what you would consider to be healthy or nutritious foods, are acceptable to eat when on the keto diet.

There are also a few foods, like butter and cream, traditionally cut in a diet that are okay to eat on keto.

Foods to eat on the ketogenic diet include:

foods for ketogenic diet
  • Meat: Most meats contain 0 grams of carbs. Beef, chicken, and pork are all great to eat when on the ketogenic diet.
  • Fish: Like meats, most fish contain 0 grams of carbs and the fattier the fish, the better, like salmon. 
  • Vegetables: Non-starchy vegetables, a.k.a. those grown above ground, like cauliflower, broccoli, zucchini, asparagus, avocado, and more are more than welcome on the ketogenic diet with 1-5 grams of carbs each. This is something that vegans would love to hear. 
  • Fat: With a high-fat diet like keto, you want to add fat to your diet wherever possible. Natural fats like butter, heavy cream, coconut oil, olive oil, and avocado are great because they contain 0 grams of carbs.
  • Nuts: Other than cashews which are high in carbs, nuts are safe to eat on the keto diet but only in moderation as it is easy to overeat nuts.
  • Berries: Fruits can be high in natural sugars and, therefore, carbs, but berries, when eaten in moderation, are safe to eat when on the ketogenic diet.

What NOT to Eat on a Keto Diet

Naturally, on a low carb diet [2], you want to avoid sugar and starch completely.

Make sure to read nutrition labels because carbs can come from some unlikely sources. 

Keto diet foods do not include:

avoid carbohydrates
  • Carbs: Naturally, on a low carb diet, you want to avoid carbs wherever possible. This includes bread, pasta, potatoes, and even beans, some fruits, and anything with sugar in it.
  • Low-Fat Dairy: Since keto is a high-fat diet, low-fat options just don’t cut it. Avoid eating anything with a low-fat label such as skim milk and fat-free yogurts.
  • ​Certain Fruits: Fruits like bananas, apples, pineapples, oranges, and grapes are healthy, but on the ketogenic diet, you can’t eat them because the natural sugars equal carbs. Just one piece of fruit could use up all your carbs for the day.
  • Processed Foods: Processed foods can seem okay on the surface but have hidden carbs that you may not be aware of. This means that you shouldn’t eat processed meats like hot dogs, salami, beef jerky, chicken nuggets, and canned meat.
  • Packaged Foods: A good rule of thumb is if it comes in a package, don’t eat it. This includes chips, cakes, candy, and even frozen dinners.
  • ​Fast Food: Fast food is good to cut out no matter what diet you are on. Between all the preservatives and grease, fast food could ruin your keto diet in one meal.

What to Drink on a Keto Diet

What you drink is just as important as what you eat on a diet.

Drinks add up and count towards your daily carb intake, just like food.

These drinks are perfectly safe to drink on the keto diet:

drinking water is good for ket
  • Water: We all need to drink more water. With 0 calories, 0 carbs, and all of the health benefits, water should be your go-to drink every day. Sparkling water, club soda, and seltzer are also fine to drink.
  • Plain Coffee and Tea: Without being loaded with milk and sugar, coffee and tea are great to drink on the ketogenic diet. If you can’t seem to stomach your coffee black or tea plain, keto-approved additions include heavy cream and stevia sweetener.
  • Diet Soda: Diet soda is like soda except without all the sugar, making it perfectly fine for the ketogenic diet.
  • Certain Alcohol: Vodka, rum, gin, tequila, and whiskey all have 0 grams of carbs, so drink up! Dry wine is okay on occasion, but don’t overdo it since it does contain natural sugars.

What NOT to Drink on a Keto Diet

​Many drinks that we think are healthy actually have hidden ingredients and carbs that can stop your keto diet in its tracks.

These are the drinks you should not be having while on the keto diet:

sodas
  • Milk: Milk is loaded with natural sugars and, therefore, carbs, so cut this out completely and choose almond milk instead.
  • ​Juice: Since juices are made from fruits and their natural sugars, the carbs in juices can add up. Some low-carb alternatives exist, so look for these if you still want to drink juice.
  • Soda: Soda is loaded with sugar and other unhealthy additives, so choose to drink diet soda instead.
  • Beer: Beer is made from wheat, an ingredient you already know you need to cut out on the ketogenic diet, especially because the carb count from this can be outrageous.
  • ​Energy Drinks: Energy drinks are full of sugar, so just cut these out completely. There are several low-carb energy drinks available if you still need a boost of energy.
  • ​Vitamin Waters: These can seem like a good idea, but the hidden sugars in these drinks can take you well over your total carb count for the day.

How Many Carbs are Allowed on the Keto Diet?

carb chart for keto diet

On the keto diet, you can eat as low as 10-20 grams of carbs a day but not more than 50 grams of carbs to achieve ketosis.

The fewer carbs you eat, the better and easier it is to achieve and maintain ketosis.

The amount of carbs you can eat varies on factors such as your activity level, so it is always recommended to consult a doctor before drastically changing your diet.

To know how many carbs you are eating a day, read the nutrition labels of foods you eat and count the net carbs, which are total carbs minus the carbs from fiber.

Fiber carbs do not count towards your net carbs because your body digests it differently, and it can actually be good for ketosis.

Is the Keto Diet Healthy?

​Yes, the keto diet is healthy if you execute it correctly.

Now there is still plenty of criticism around this diet, mainly around the lack of long-term research on it and the side effects of those with preexisting conditions who take up the ketogenic diet. But so far, the research has been promising. 

Along with weight loss, health parameters associated with carrying excess weight have improved, such as insulin resistance, high blood pressure, and elevated cholesterol and triglycerides.

​Harvard School of Public Health



Further research needs to be done on the long-term effects of the ketogenic diet and those with certain health conditions and diseases such as diabetes and high blood pressure should not start the diet without consulting a doctor.

Other than those considerations, the ketogenic diet is completely healthy! 

What are its Benefits?

lady with benefits signage

The ketogenic diet has proven to have a number of health benefits from weight loss [3] to the control of diseases such as diabetes. Yes, people do get into this low-carb, high-fat diet for more than just fat loss.

As more research is conducted on the keto diet, even more benefits may come to light. For a full guide on the benefits of adopting this diet, keep reading.

1. Fights Diabetes

​The ketogenic diet has the potential to reduce, or remove altogether, the need for those with type 2 diabetes to use insulin.

The decrease in carbs in your diet keeps you from having large spikes in blood sugar. The diet also keeps glucose levels low but healthy, another bonus for those with type 2 diabetes (Wu).

2. Helps Lose Weight

weight loss

​The keto diet has drastically increased in popularity recently thanks to its proven weight loss benefits.

By getting your body to burn fat instead of carbs for energy, you achieve ketosis, which turns all the fat in and on your body into energy.

Achieving ketosis also helps you burn fat 24/7, provides you with more energy all day long and suppresses your appetite, all of which are key factors in weight loss (Mawer).

3. Improves Overall Health

​When on the keto diet, users have reported experiencing better overall health.

Not only does this diet give you more energy and help you lose weight, both very healthy improvements, but it also affects several different areas of your body.

Basically, on the ketogenic diet, your body is at its peak performance. Even your brain is functioning better.

When your whole body is in tip-top shape, you will certainly start to notice it in your health.

4. Improves Mental Performance

health benefits

​The keto diet has been used by doctors for decades to improve certain brain functions in patients.

The ketones produced during ketosis are a great backup source of energy in certain neurodegenerative diseases such as Alzheimers, Parkinsons, and epilepsy where the patient’s brain cannot use enough glucose to continue normal functioning (How).

The diet has also shown to increase memory and focus in dieters.

5. Suppresses Appetite

Cravings are usually caused by spikes in blood sugar. Since the ketogenic diet stabilizes blood sugar by removing the need to use sugar as energy, you won’t experience any more cravings. [4]

The ketogenic diet also keeps the hunger hormone ghrelin at bay, so you can kiss those hunger pains shortly after you eat a meal goodbye! (Crawford)

6. Gives More Energy and Physical Endurance

man doing workout with dumbells

​You probably feel slumps in energy several times a day on a normal diet.

This is usually due to the extra glucose in your bloodstream that your body didn’t convert to energy. 

Those dips in energy go away altogether on the keto diet because instead of needing food for energy, your body can just tap into the fat on your body for energy any time it needs a boost (Gustin). This also means you have energy 24/7.

7. Helps with Epilepsy

​The ketogenic diet actually started in the 1920s as a way to treat epilepsy and seizures in children.

The diet is still used today for patients who have seizures even when on medications such as AEDs. Studies show this is due to the decanoic acid which is produced alongside ketones and helps control seizures in some patients (Ketogenic).

8. Improves Stomach Health

lady flat belly

The keto diet promotes better overall stomach health because cutting out carbs starves the bad stomach microbes that eat sugar, and feeds the good stomach microbes that thrive on eating healthy fats and veggies.

The healthy fats you ingest are also good for your stomach lining. This means improved digestion, a stronger immune system, and, quite possibly, better sleep (Allen).

9. Battles High Blood Pressure

​High blood pressure is often associated with being overweight. Any diet that effectively helps you lose weight should, in turn, lower your blood pressure.

But some studies show that the ketogenic diet in particular can reduce the need for medication in patients with high blood pressure, especially when compared to those on low-fat diets (Can). 

The keto diet can also help level out cholesterol levels.

10. Fights Acne

acne problem

Higher insulin levels and spikes can increase the amount of sebum and androgens in your skin and increase acne. But with a low-carb diet like the keto diet, many dieters notice decreased acne and clearer skin.

The ketogenic diet effectively lowers insulin levels and has anti-inflammatory properties that can reduce redness and breakouts. (Eenfeldt, Spritzler)

Other Potential Benefits

While the benefits listed above are the most common, dieters have noted other benefits from starting and sticking to the keto diet.

These other benefits include reducing migraines, getting rid of heartburn, and reversing polycystic ovary syndrome. (Eenfeldt, Scher)

 The ketogenic diet is also undergoing research as a possible treatment for brain cancer. [5]

​Keto Diet Reviews & Success Stories

suceess stories

When starting a diet, it can be hard to know which diet is the one for you. The best way to find out if you should start the keto diet is to read firsthand experiences.

Here are some real experiences that speak to the effectiveness of the ketogenic diet:

Keto for Weight Loss

Kimberly started the keto diet in September of 2016. She started the diet because she had body image issues and low self-esteem for years. She also said she had three young children that were looking up to her and she wanted to set a good example.

Two years later and Kimberly has lost 131 pounds and, more importantly, she said :

On this journey, I have found my own inner strength. I have overcome debilitating anxiety and severe mood swings. I’ve discovered a passion for hiking and exploring. I have taken my life back.

​Kimberly

Keto for Diabetes

Lele Jaro was diagnosed with type 2 diabetes in 2006 and struggled with her blood sugar for years. When she and her doctors decided that she should give keto a try, she finally felt like she had control over this chronic disease.

In fact, within the first few months of the diet, she was able to cut her daily units of insulin down from 100 to 75.

I’m no longer on insulin, and I have cut down my medications due to keto. I never had to deal with trying to find a spot to inject or having to deal with bruises on my belly.

​Lele Jaro

Keto for Brain Cancer

brain examines

​Thomas Grobicki started the keto diet in 2016 soon after his daughter Alina was diagnosed with glioblastoma, a fast-growing brain cancer with an average survival time of 12 months.

The diet was a recommendation for Alina to do alongside her medical treatments and Thomas joined her as a coach and chef.

Two years later, Thomas lost 105 pounds from this lifestyle change. And as for his daughter, “Alina is a cancer survivor. We are now two years beyond her initial diagnosis. There has been no evidence of tumor regrowth. The ketogenic diet may have helped.”

Here are some videos as well:

Here's one that featured on Dr. Oz.

Here's another amazing transformation.

Ketosis - How to Get There:

Getting into ketosis isn’t hard—it only takes restricting your carbs, monitoring the foods you eat, exercising, and getting plenty of sleep.

With a little perseverance, you will be in ketosis in no time.

Use these helpful tips to get yourself into ketosis:

  • ​Eat no more than 20 grams of carbs a day. The lower your carb count, the quicker and longer you will be in ketosis.
  • ​Don’t eat too much protein. Protein is a part of the ketogenic diet, but it is not something you need extra of. Too much protein may even keep you from achieving ketosis. Try to only eat 1.5 grams of protein a day.
body goals
  • ​Eat plenty of fat. Fat fuels the keto diet and keeps you full and satisfied. If you find yourself hungry and about to give up, try adding more fat to your diet.
  • ​Don’t snack, especially if you are not hungry.
  • ​Exercise. Physical activity slightly increases ketone production.
  • ​Get plenty of sleep. Lack of sleep leads to stress which leads to an increase of hormones and blood sugar levels, thereby slowing the production of ketones and halting ketosis.
  • ​Try intermittent fasting. This means eat for 8 hours of the day and fast for the remaining 16. This gives your metabolism an added boost and boosts ketone production.

How to Know if You’re in Ketosis?

​There are several signs that you are in ketosis including weight loss, increased energy, and a positive result from a ketosis test.

If you follow a strict keto meal plan and even count your net carbs, you will enter ketosis within a few days to a week.

guy working out

Doctors can test for the presence of ketones in your blood, breath, or urine to find out if you are in ketosis, but you don’t have to go to a doctor to find out for sure.

There are several at-home testing kits, breath analyzers, and testing strips available for you to purchase so you can test yourself at home.

While a test is the best way to know that you are definitely in ketosis, your body will also show several different signs of starting to produce ketones as well.

If you lose weight, have more energy, and are able to focus and concentrate more, chances are, you are in ketosis.

There are also a few side effects from switching over to the ketogenic diet and these are sometimes known as part of the “keto flu.” If you experience these side effects, your body is in the process of switching into ketosis and will soon subside as you get further into the diet and your body adapts.

Some of the keto flu side effects include bad breath, increased thirst, headaches, muscle cramps and spasms, fatigue, changes in sleep patterns, and an upset stomach.

If any of these side effects occur and last longer than a few days, consult a doctor about your switch to the keto diet and make sure there are no underlying problems.

Reaching Optimal Ketosis

ketones level diagram

There are different levels to ketosis, so testing your blood or urine for the presence of ketones is the best way to know how far along you are.

If you test your blood and see results lower than 0.5 mmol/L, you are far from being in ketosis.

If your result is 0.05 - 1.4 mmol/L, you are in ketosis but still have further to go.

Results of 1.5 - 3.0 mmol/L means you have reached optimal ketosis.

If you test yourself and are shocked to see that you are still far away from optimal ketosis, there are a few things you can do.

First of all, make sure you are testing yourself first thing in the morning before you eat. This will provide you with the most accurate results.

From there, you may want to start strictly monitoring your protein and fat intake. Eating too much protein can keep you from reaching optimal ketosis and not eating enough fat can do the same thing. Try adding more fat to your diet through “bulletproof coffee” where you add a tablespoon of butter or coconut oil to your morning coffee, or by making and eating fat bombs for dessert or snack.

Not only is eating more fat good for the keto diet in general, but eating more fat will also fill you up and keep you satisfied so you can make sure you do not eat too much protein. 

Are There Potential Side Effects From the Keto Diet?

questioning side effects

Side effects from the keto diet include low libido, headaches, fatigue, dizziness, vomiting, constipation, irritability, frequent urination, increased thirst, bad breath, and muscle cramps or spasms.

With the frequent urination comes the risk of losing too many electrolytes and doing damage to your kidney and heart. Loss of electrolytes can strain the kidney and heart, so make sure you are staying hydrated and replacing those electrolytes if you are urinating frequently.

This is also known as the keto flu, or side effects your body goes through as it starts to adjust to being on the ketogenic diet.

Side effects of the keto flu should subside as your body adapts to being in ketosis. If they do not, consult a doctor about your change in diet.

Also, it's quite important to note that a lot of keto supplements like BHB and MCT oils are known to help battle the symptoms of the keto flu or any adverse effects from the keto diet. 

About the Author

Ryan is a personal trainer, athlete, health enthusiast, and entrepreneur. He is researching and expanding his knowledge about the ketogenic diet. He spends most of his time writing content about his new learnings of the ketogenic diet and shares it on Ketogenic Supplement Reviews. You can find me on: Facebook, Twitter and Pinterest.