The Ketogenic Diet (Keto Diet)

A detailed beginner’s guide to keto and diabetes.

A keto diet is a low-carb, high-fat diet that shares many similarities with the Atkins Diet and other low-carb diets. The main difference between keto and other low-carb diets is that you will be eating moderate amounts of protein but almost no carbohydrates while on the keto diet. This puts your body into a state called ketosis, which has many benefits for controlling blood sugar, weight loss, and overall health. 

This comprehensive guide will break down everything you need to know about the ketogenic diet, including what it is, how it works, what to eat, what not to eat, health benefits, and potential side effects.

What Is a Ketogenic Diet?

Keto Basics

The ketogenic diet is a very low-carb, high-fat diet that shares many similarities with the Atkins Diet and low-carb diets.

Your body naturally breaks down the carbohydrates you eat into glucose (sugar). Glucose is then used as your body’s primary energy and fuel source.

Railway junction with one sign labeled "glucose" leading to a dead end and the other labeled "ketones" leading to the distance

On a keto diet, you drastically reduce your carbohydrate intake and increase your consumption of healthy fats. This reduction in carbs puts your body into a metabolic state called ketosis.

Ketosis is a metabolic state in which your body has run out of its glycogen (the storage form of glucose). After this happens, fat becomes the primary energy source for your body.

In ketosis, you break down fats into fatty acids and glycerol to fuel your cells. In other words, you’re literally using stored fat as an energy source.

Following a keto diet can cause your blood sugar and insulin levels to drop significantly. The drop in insulin results in the body burning more fat. As a result, it becomes easier to lose weight while feeling less hungry. In addition, energy levels are more constant due to eliminating blood sugar highs or lows.

Different Types of Keto Diets

There are several different types of keto diets:

  1. Standard ketogenic diet (SKD): This is a very low-carbohydrate with moderate-protein and high-fat diet. It typically contains 70% fat, 20% protein, and only 10% carbohydrates.
  2. Cyclical ketogenic diet (CKD): This diet involves periods of higher carbohydrates between the ketogenic diet cycles. For example, five ketogenic days followed by two high-carbohydrate days as a cycle.
  3. Targeted ketogenic diet (TKD): This diet permits adding additional carbohydrates around the periods of the intensive physical workout.
  4. High-protein ketogenic diet (HPKD): This diet includes more protein and the ratio of around 60% fat, 35% protein, and 5% carbohydrates, but as can be seen, it is still a very high-fat diet.

The SKD and HPKD have been used extensively. The cyclical and targeted ketogenic diets are recent additions and are primarily used by bodybuilders or athletes. The SKD is the most researched and recommended out of all the variations of keto diets.

Who Should Follow a Keto Diet?

A keto diet is a restrictive low-carb, high-fat (LCHF) diet and should not be initiated unless you have consulted with your doctor to determine if it is safe. You should not follow a keto diet if:

  1. You have diabetes and take insulin*, take medication for high blood pressure, or have any other disease or illness that requires medication; a keto diet can be unsafe.
  2. You are pregnant or breastfeeding. This can be unsafe for both you and your baby.
  3. You are under the age of 18. You may not get all of the micronutrients your body requires for healthy growth.

Always check with your doctor before making any changes in your diet.

*A keto diet causes your blood sugar levels and insulin production to drop. Because of this, if you are taking diabetes medications, including injected insulin, you can experience dangerously low blood sugar levels called hypoglycemia. A keto diet has many benefits for people with diabetes; however, you MUST consult with your doctor before changing your diet to adjust your medications safely.

Fasting and Keto

Many people find incorporating fasting along with a keto diet yields positive results. Both intermittent fasting and extended fasting can be used with a keto diet. People often find it is easier to begin fasting once their body is in ketosis and their appetite and cravings decrease.

You may find that fasting also helps your body enter ketosis faster than making diet changes alone.

Always consult with your doctor before starting any type of fasting.

Benefits of a Keto Diet

There are several health benefits of following a keto diet, similar to other low-carb, high-fat (LCHF) diets. However, a keto diet is more restrictive and will provide quicker and more dramatic results than most other low-carb, high-fat diets.

Woman standing on the scale while adjusting the weight smiling.Insulin levels drop significantly during ketosis while on a keto diet. Insulin is a hormone responsible for storing fat. Not only are you storing less fat on this diet, but your body is burning the fat it already has. When the body switches from burning carbohydrates for energy to burning fat for energy, the body starts burning body fat for fuel at a much more rapid rate.

Low-carb, high-fat diets are proven to reduce blood sugar levels. If done properly, a low-carb, high-fat diet can help reverse type 2 diabetes. As a result, many people no longer require medication to treat their type 2 diabetes.

For someone without diabetes, a keto diet can help prevent type 2 diabetes or eliminate prediabetes. Reversing type 2 diabetes consists of making lifestyle changes to get your A1C into a normal range without medications to maintain healthy blood sugar levels.

Following a keto diet can help improve insulin sensitivity. This means your cells are less resistant to insulin (the root cause of prediabetes and type 2 diabetes).

Improving blood markers is another benefit of a keto diet. Cholesterol and triglycerides are reduced, while good (HDL) cholesterol increases. As a result, blood pressure typically lowers, as well as blood sugar and bad (LDL) cholesterol. All of these factors help reduce the risk of heart disease.

By reducing carbohydrates and increasing fat, you’re not going to feel hungry as often on a keto diet. Cutting back on the cravings means you eat less often, making it much easier to gain control of your blood sugar levels.

Reducing gluten intake and other potential negative nutrients can help reduce stomach issues, including gas, cramps, and pain. This can often be noticed in as little as a few days into a keto diet.

Increase Energy and Better Mental Performance

African American woman jumping rope outside in a park.A keto diet improves cognitive functioning and aids in slowing down cognitive decline. As a result, Alzheimer’s patients benefit from the diet. For people with diabetes, following a keto diet can help slow down the progression of Alzheimer’s or help prevent the disease. Avoiding blood sugar spikes and valleys also helps maintain a more consistent and better flow of concentration throughout the day.

Improve Physical Endurance

Changing fuel sources in the body means your body has access to a longer lasting fuel supply. Carbohydrates typically only last for two or three hours of intense exercise, but fat stores can last for two or three weeks.

A keto diet may potentially mean fewer anti-epileptic drugs or even no medications for epilepsy. In turn, side effects from medications would be eliminated. Becoming and remaining seizure-free could be another benefit of a keto diet.

Keto Macros: Carbs, Protein and Fat

The standard keto diet typically contains 10% carbohydrates, 20% protein, and 70% fat.


You want to limit your net carb intake to 20 grams or less per day on a keto diet. Net carbs are calculated by taking the total carbs and subtracting the fiber. By eating 20 grams or less per day, you should be able to maintain a state of ketosis.


Remember that most keto diets are moderate protein. A common mistake is to go overboard with protein on a keto diet. The standard keto diet is not the same as a high-protein diet or carnivore diet. Your exact amount of protein needed will vary by weight, gender, and physical activity. Most people need at least 70 grams of protein per day. It may be helpful to aim for 20-30 grams of protein per meal.


Ketogenic (keto) diet macros displayed in a circle pie chart.Fat is an essential part of a keto diet. You want to make sure you’re eating healthy fats like olive oil, butter, and avocados rather than processed trans-fats. Learn more about the different types of fat here. On a keto diet, about 70% of your daily calories come from fat. You want to be mindful of not overdoing fat, especially if you’re trying to lose weight. If you add too much fat to your diet, your body won’t be able to burn stored fat for energy.

Foods to Eat on a Keto Diet

Top view looking down at a table with low-carb, high-fat foods displayed. Foods to eat on a keto diet.

  • Nuts and seeds – Pistachios, almonds, walnuts, macadamia nuts, pumpkin seeds, and chia seeds
  • Non-starchy vegetables – Cauliflower, green beans, mushrooms, peppers, broccoli, green beans, and other greens
  • Fish – All fish are good, but especially high-fat fish such as salmon, trout, and sardines
  • Meat and poultry – Red meat, turkey, chicken, and venison
  • Full-fat dairy products – Cream, butter, and cheese
  • Oils – Olive, coconut, and avocado
  • Berries – In moderation, blueberries, blackberries, strawberries, and raspberries provide antioxidants.
  • Condiments – Fresh herbs, spices, and pepper

Foods to Avoid on a Keto Diet

  • Sugar and sugary drinks – Soda, juices, sweetened tea, sports drinks, chocolate milk, eggnog, and smoothies
  • Sweeteners – Sugar, honey, maple syrup, and agave
  • Highly processed foods – Pre-packaged food and meats in the form of “instant lunches,” processed deli meats, and highly processed bacon, sausages, and hot dogs
  • Grains and starches – Bread, pasta, cereal, baked goods, and rice
  • Alcoholic drinks – Beer, sugary drinks, and wines. Alcohol can both increase and lower blood alcohol levels. If you have diabetes, you should approach alcohol with caution.
  • Low-fat foods – Many low-fat foods are high in sugar. Foods labeled with keywords such as “diet,” “light,” and “low-something” are typically not healthy. Processed foods are typically used to make up for not missing nutrients.
  • Starchy vegetables – Potatoes, squash, corn, etc.

Carbohydrate-heavy alcohol can raise blood sugar levels significantly. Conversely, hard liquors mixed with water or drinks with no sugar can substantially lower blood sugar levels. This can be extremely dangerous and sometimes fatal for people with diabetes if not blood sugar levels are not closely monitored with a continuous blood glucose monitor (CGM).

Healthy Keto Snacks

Healthy ketogenic (keto) snacks to eat, avocado, egg, peppers, nuts and seeds.Here are some healthy keto approved snacks for in-between meals.

  • a handful of nuts or seeds
  • hard-boiled or deviled eggs
  • olives
  • cheese
  • bell peppers with guacamole
  • full-fat Greek yogurt with nut butter
  • beef jerky (no sugar added)
  • fat bombs
  • cottage cheese and strawberries
  • dark chocolate (90%)

Micronutrient Deficiencies on a Keto Diet

Closeup view of vitamin and supplement pills for a keto diet on a dark background.It is possible to experience side effects if your diet does not have enough variation to ensure you receive needed micronutrients. Micronutrients are often referred to as vitamins and minerals.

When following a keto diet, we recommend having your blood tested at least annually to check and ensure you don’t have any deficiencies. Blood tests are the only way to know what your levels are. If you find you are deficient in one or more vitamins or minerals, your doctor may suggest taking supplements. 

Learn more about vitamins and supplementation:

The “Keto Flu”

Feeling sick is a side effect of changing your diet, especially if you are used to eating sugars and starchy carbohydrates. As a result, you may experience flu-like symptoms. Specifically for a keto diet, your body enters a state of ketosis, where your body burns fat for energy instead of glucose.

When your body breaks down fats as energy, ketones are produced. These ketones need to be removed from your body, which usually happens in the form of more frequent urination. 

Dehydration is often the result, which can produce the following flu-like symptoms:

  • Constipation
  • Diarrhea
  • Nausea
  • Weakness
  • Fatigue
  • Dizziness
  • Headaches
  • Muscle cramps

Frequent urination can also result in the loss of electrolytes, which tends to amplify your symptoms.

Cutting back significantly on carbohydrates can often create sugar cravings, as your body is accustomed to using glucose (sugar) from all of the carbohydrates you have been eating. It may take up to a week for your body to adjust to burning fat instead of glucose for energy. You may also experience difficulty concentrating during this time, such as brain fog.

Other Symptoms

Long-term, a keto diet usually leads to a deeper sleep and requires less sleep to help the body recover from the day. However, adopting a keto diet can cause lower levels of serotonin and melatonin, which can cause interrupted sleep and sometimes a brief period of insomnia.

Some essential electrolyte loss can include sodium, magnesium, and potassium. A shortage of these electrolytes can lead to acute kidney injury or kidney stones. Even further, cardiac arrhythmia may become an increased risk, which can be deadly.

It is critical to drink plenty of water and ensure that you receive enough electrolytes, especially during the first week of your keto diet. Be sure to check with your doctor before making any diet changes and reach out to your doctor if you are having difficulty with the diet change or experiencing any concerning symptoms.

Total Diabetes Wellness' Recommendations

We recommend following a low-carb, high-fat diet.* Following a keto diet typically has excellent results for people with diabetes, with blood sugar levels coming under control quickly and insulin sensitivity improving rapidly.

However, a keto diet can be difficult to maintain long term. For this reason, we recommend starting with a low-carb diet with a daily carbohydrate consumption of 50-100 net grams. (For reference, a standard keto diet has 20 grams of net carbs per day). This bigger allowance of carbs will allow you to include a wider variety of healthy foods in your diet and not feel as restricted. Many people find this version of low-carb, high-fat much easier to maintain for the long run.

The health benefits of a keto diet can also be obtained by following the low-carb, high-fat diet we recommend.

If you want to give a keto diet a try, we hope you will find the information in this article helpful to get started. A keto diet can have significant benefits to your overall health.

*Always discuss diet changes with your doctor or physician before beginning. A low-carb, high-fat diet generally benefits people with all types of diabetes. However, if you are on any diabetes medications, you need to be especially careful.