Ketogenic Diet With Type 1 Diabetes: Is It Safe?

The ketogenic (or keto) diet is a very low-carbohydrate and high-fat diet that has become popular in the past few years. It is a popular nutritional strategy for weight loss.

Some people have suggested a keto diet can control symptoms in patients with several brain and metabolic disorders. But what about type 1 diabetes? 

First, let’s learn about the keto diet and the key differences between ketosis and ketoacidosis.

What is a ketogenic diet? 

The ketogenic diet¹ is a high-fat, moderate-protein, and low-carbohydrate diet. It’s become quite a popular weight-loss diet over the last few years. The goal of the ketogenic diet is to reach a state of ketosis when the body generates much more energy from fat than sugar. 

Ketosis and diabetic ketoacidosis are completely different states. 

Diabetic ketoacidosis 

Diabetic ketoacidosis² is a medical emergency when your body runs out of insulin, so it uses fat for energy. This causes a high production of ketones, leading to changes to the blood pH that can be potentially life-threatening.

Diabetic ketoacidosis can wreak havoc on your brain, kidney, liver, and blood vessels if you don’t receive prompt treatment. 

Nutritional ketosis

In nutritional ketosis, reduced intake of carbohydrates decreases insulin secretion. Consequently, it promotes fat to use for energy, storing less fat and increasing ketone production.

The primary difference between nutritional ketosis and diabetic ketoacidosis is that nutritional ketosis generates fewer ketones, causing minor changes in blood pH.

How does the ketogenic diet work for type 1 diabetes? 

As the ketogenic diet decreases insulin release, which could benefit some people, you may wonder if it’s effective for people with type 1 diabetes. It can be, but many serious complications can arise from a ketogenic diet.

Therefore, you should work with a medical professional if you want to try keto. 

Is the ketogenic diet effective for type 1 diabetes? 

Few studies have addressed whether the ketogenic diet works in people with type 1 diabetes. A randomized trial³ found that a low-carbohydrate diet is a valid option for people with type 1 diabetes who want to reduce their insulin dose. It also suggested that a keto diet can be especially beneficial for people trying to lose weight, which may improve the symptoms of type 1 diabetes. 

Can the ketogenic diet help manage type 1 diabetes? 

The evidence is a bit conflicting about whether a ketogenic diet assists in managing the symptoms of type 1 diabetes or not. It seems like the diet helps control type 2 diabetes, allowing some patients to reduce the amount of medication they take or discontinue it altogether. 

For type 1, very low-carbohydrate diets such as the keto diet control symptoms in some children and adults, according to a self-reporting study.⁴ However, potential benefits may come with adverse effects such as high blood cholesterol levels and increased hypoglycemic episodes.

Who should avoid following a keto diet?

While a keto diet can be beneficial, it may not be safe for everyone. People who should avoid a keto diet include: 

• Children and teenagers: Diets that drastically change the nutrients you consume can stunt growth and development.

• People recovering from sickness or medical treatment: The risk of blood sugar falling too low and ketone production rising too high increases

• People with high cholesterol: High-fat diets can increase cholesterol further and influence heart disease risk

• People who struggle to stop their blood sugar from falling

If any of these apply to you, you’re more likely to suffer serious adverse effects. Don’t start a diet without the recommendation of a medical professional. 

What are the side effects of the ketogenic diet in type 1 diabetes?

Scientists don’t unanimously recommend the keto diet for people with type 1 diabetes. They may be at an increased risk of experiencing side effects, and the diet may worsen some diabetes symptoms. 

Keto may lower blood sugar too much 

A keto diet can cause blood sugar to drop excessively in people with diabetes because it is so low in carbohydrates. Symptoms of low blood sugar (hypoglycemia)⁵ include slurred speech, dizziness, and loss of consciousness.

If this happens often, the risk of losing consciousness or causing damage to the heart, nervous system, and eyes increases. It may be best to avoid the keto diet if you often have episodes of low blood sugar. 

The keto diet may cause unwanted weight loss 

The keto diet seems to be very effective for weight loss. The keto diet promotes more weight loss in the short term compared to standard diets with the same calorie intake. A keto diet seems at least as effective for weight loss as a low-fat diet in the long term, but it can cause an increase in cholesterol. 

Nutritional ketosis suppresses your appetite following weight loss, making it harder to regain the weight. 

For some people, weight loss might seem like an advantage of the keto diet. However, it's best to avoid the diet if you’re underweight or in a situation where weight loss or increased cholesterol may be detrimental to your health.

It may require insulin reduction

Since blood sugar levels do not rise as high on the keto diet compared to others, you may need to reduce your insulin doses. A study has found that people with diabetes on a low-carbohydrate diet required an average of 20 fewer units of insulin per day than those on a standard diet. 

That becomes pretty risky if you take the same amount of insulin as usual when you start the keto diet. It’s best to get medical advice to be sure you don’t risk episodes of low blood sugar, and your doctor will advise how much insulin you need. 

Important warnings for people with type 1 diabetes attempting a keto diet

If you have type 1 diabetes and are considering following a keto diet, keep the following cautions in mind to stay as safe and healthy as possible. 

If you manage your diabetes well, a keto diet can be safe. Nevertheless, it may be best to start with a slow reduction in carbohydrate intake to test if your body can manage it first. 

Don’t start keto unsupervised 

A ketogenic diet is not suitable for everyone, and safely undertaking a keto diet can be pretty tricky. Speak with your doctor before you begin and throughout the diet. 

Your doctor or dietitian can help you plan your diet while managing your diabetes and medications. They may also advise against the keto diet if they feel you’re at a greater risk of complications. 

If that’s the case, you may need to spend time getting well enough to undertake a keto diet without complications. Listening to your doctor’s guidance ensures you can follow the diet safely and sustainably without serious problems arising. 

Monitor your ketone levels

It’s crucial to monitor your blood ketone levels⁶ while on a keto diet to ensure you don’t develop ketoacidosis. 

Your doctor will likely advise you to check your blood ketone levels regularly. Watch out for any symptoms of ketoacidosis, like a spike in blood sugar (above 16.6 mmol/L), nausea, confusion, or feeling ‘in a fog.’ 

That allows you to quickly seek treatment if you do enter a state of ketoacidosis. 

The lowdown

A keto diet can be very useful in controlling and managing diabetes symptoms. However, the diet isn’t suitable for everyone.

For example, you may have problems with blood sugar, ketoacidosis, or increased cholesterol. It’s essential to consult a medical professional before starting and during your time on the diet. 

You should monitor your blood ketones to ensure you don’t develop ketoacidosis. The overall safety of the ketogenic diet for someone with type 1 diabetes depends on many factors, especially how well you manage your diabetes.

Your doctor will be able to advise if it’s suitable for you.