Key takeaways

  • The ketogenic, or keto, diet involves consuming high amounts of healthy fats, adequate protein, and very few carbohydrates, which causes the body to use fat for energy instead of sugar.
  • Following a keto diet may offer benefits such as supporting weight loss, improving acne, enhancing heart health, protecting brain function, and improving polycystic ovary syndrome (PCOS) symptoms.
  • Despite its potential benefits, the long-term effects of the ketogenic diet are not yet well-studied, and it may lead to adverse health issues such as kidney stones, liver disease, and vitamin deficiencies, in addition to common short-term side effects known as “keto flu.”

The keto diet is an eating plan that focuses on foods that provide a lot of healthful fats, adequate amounts of protein, and very few carbohydrates. The goal is to get more calories from fat than from carbs.

The diet works by depleting the body of its sugar reserves. As a result, it will start to break down fat for energy. This results in the production of molecules called ketones, which the body then uses for fuel.

Read on to learn more about the possible benefits and risks of the keto diet.

The ketogenic diet may help promote weight loss or management in several ways, such as by boosting metabolism.

The keto diet may also help with managing weight reduce appetite though more research is necessary to better understand this.

Acne has several different causes and may have links to diet in some people.

For example, eating a diet high in processed foods and refined sugar may cause or worsen symptoms of acne.

While more research is necessary, following a keto diet may help reduce symptoms of acne or reduce the likelihood of it occurring.

Entering ketosis, where the body uses ketones rather than glucose for energy, may also help with managing inflammation, a symptom of acne.

Some research suggests that the keto diet may help improve heart health.

A 2017 review of studies of animals and humans on a keto diet showed that some people experienced a significant drop in levels of:

  • total cholesterol
  • low-density lipoprotein (LDL), or “bad,” cholesterol,
  • triglycerides

They also saw an increase in high-density lipoprotein (HDL), or “good,” cholesterol.

High cholesterol levels can increase the risk of cardiovascular disease. A keto diet’s reducing effect on cholesterol may, therefore, reduce a person’s risk of heart complications.

However, the review concluded that the positive effects of the diet on heart health depend on diet quality. It’s important to eat healthful, nutritionally balanced food while following the keto diet.

A 2019 review suggests the ketones that generate during the keto diet provide neuroprotective benefits, which means they can strengthen and protect the brain and nerve cells.

For this reason, a keto diet may help a person prevent or manage conditions such as Alzheimer’s disease.

However, more research is necessary into a keto diet’s effects on the brain, and specificically on Alzheimer’s disease.

The ratio of fat, protein, and carbs in a keto diet alters the way the body uses energy, resulting in ketosis. Ketosis is a metabolic process during which the body uses ketone bodies for fuel.

The Epilepsy Foundation suggests that ketosis can reduce seizures in people with epilepsy, especially those whose condition has not responded to other treatment methods.

More research is necessary on how effective this is, though it seems to have the most effect on children who have focal seizures.

A 2019 review supports the hypothesis that a keto diet can support people with epilepsy. It may reduce epilepsy symptoms by several different mechanisms.

Polycystic ovary syndrome (PCOS) is a hormonal disorder that can lead to excess male hormones, ovulatory dysfunction, and polycystic ovaries.

A 2019 review of studies found that a keto diet had beneficial effects for people with hormonal disorders, including PCOS.

However, the review did also caution that the studies were too diverse to recommend a keto diet as a general treatment for PCOS.

More research is necessary to better understand the possible benefits of the keto diet on PCOS symptoms.

Some researchers have examined the effects of the ketogenic diet in helping prevent or even treat certain cancers.

A 2024 study suggests that, since cancer cells are dependent on glucose, following keto may help reduce the likelihood of cancer.

Although some research indicates that the keto diet may have some benefit in cancer treatment, studies in this area are limited.

Researchers need to carry out more studies to fully understand the potential benefits of the ketogenic diet in cancer prevention and treatment.

The keto diet may have a range of health benefits. However, staying on the keto diet long-term can have an adverse effect on health, including an increased risk of the following health problems:

  • kidney stones
  • excess protein in the blood
  • mineral and vitamin deficiencies
  • a buildup of fat in the liver

The keto diet can cause adverse side effects that many people know as “keto flu.” These adverse effects may include:

These symptoms are especially common at the beginning of the diet as the body adjusts to its new energy source.

Some people should avoid the keto diet, including:

  • people with diabetes who are insulin-dependent
  • people who have eating disorders
  • people with kidney disease or pancreatitis
  • people who are pregnant or nursing

People who take a type of medication called sodium-glucose cotransporter 2 (SGLT2) inhibitors for type 2 diabetes should also not follow a keto diet. This medication increases the risk of diabetic ketoacidosis, a dangerous condition that increases acidity in the blood.

The keto diet may offer a range of benefits, such as promoting heart health, improving acne, and helping protect brain function.

However, studies on the long-term benefits of the keto diet are lacking. It is unclear whether maintaining this diet over longer periods is more beneficial than less restrictive, healthful eating patterns.

People looking to start the ketogenic diet should seek consultation with a healthcare professional to check if they have any underlying health conditions to ensure the keto diet is a safe eating pattern based on their individual circumstances.