Physio Hub: Evidence-Based Article

Ketogenic Diet and the Effects on Athletic Performance

Ketogenic Diet

< Key Points >

  • Health Benefits and Risks: The ketogenic diet may promote weight loss, improve gut and heart health, and could complement cancer treatments. However, it also carries risks like dyslipidemia and diabetic ketoacidosis, necessitating medical consultation before starting.
  • Impact on Athletics Ambiguous: Research on the ketogenic diet’s effects on athletic performance shows mixed results, with some studies indicating potential benefits and others showing no significant impact.
  • Personalized Diet Planning: The effectiveness and safety of the ketogenic diet vary among individuals, underscoring the importance of a personalized approach and professional guidance, especially for athletes.

The keto diet is a low-carbohydrate, high-fat, moderate-protein diet that has gained popularity in recent years for its possible weight loss benefits. It has also been used to treat various medical conditions. For instance, research in the journal The Neurologist found that the keto diet appears to be relatively safe and possibly effective as part of a treatment plan for intractable seizures. However, more research is needed before it becomes a standardized form of therapy.

The keto diet involves a macronutrient distribution that generally ranges from 55%-60% fat, 30%-35% protein, and 5%-10% carbohydrates. But what are the possible benefits of the keto diet, and is it safe for most people? The article below answers those questions.

Is the Keto Diet Good for Your Health?

The keto diet can have several health benefits. According to research in the journal Nutrients, the ketogenic diet may offer some of the following benefits: 

Promotes weight loss

A keto diet may promote weight loss for a few reasons. For instance, research in Current Nutrition Reports found that a keto diet helps promote the breakdown of excess fats and improves insulin sensitivity.

Eating a diet high in healthy fats and protein also reduces hunger and increases feelings of fullness, contributing to weight loss. A meta-analysis published in the British Journal of Nutrition indicated that people who followed a keto diet lost two pounds more than those who followed a low-fat diet over a year. 

Because a ketogenic diet may promote weight loss, it may also help reduce the risk of type 2 diabetes, which is often associated with obesity. 

Improves gut health

A person’s diet often plays a role in their gut microbiome and overall gut health. Research into the effects of a ketogenic diet on gut bacteria is somewhat limited. However, some evidence suggests that eating a keto diet may positively impact the gut microbiome and epigenome, adding to microbial diversity. 

May benefit heart health 

Although the ketogenic diet is high in fats, individuals should select healthy fats, such as olive oil, nuts, and avocados. Some research shows that eating a diet rich in healthy fats may help decrease cholesterol levels. An article published in the journal Nutrients reported that some people who follow a keto diet have a significant reduction in low-density cholesterol, triglycerides, and total cholesterol. 

Might reduce the risk of certain types of cancer

Certain studies have focused on the effects of a keto diet in helping prevent or treat certain types of cancer. For example, some research indicates that a keto diet may be safe as a complementary treatment used along with traditional cancer treatments, such as chemotherapy and radiation therapy. Research in Aging found that a ketogenic diet may lower blood sugar and potentially cause the liver to produce ketones. Ketones do not benefit cancer cells. The cancer cells may become starved of energy, which decreases their ability to multiply and grow.  

However, more research is needed to conclusively recommend a ketogenic diet in people undergoing cancer treatment. 

Lose Weight

Risks of Keto Diet

As stated above, the ketogenic diet is associated with certain potential benefits, such as short-term improvement in some chronic diseases. But there may also be some risks with following a keto diet.

Possible risks of a keto diet include: 

  • Dyslipidemia
  • Diabetic ketoacidosis 
  • Hypoglycemia 
  • Headaches 
  • Nausea
  • Constipation 

As always, it is essential to speak to a doctor before making a change to the keto diet, especially for people who have a preexisting medical condition. 

Is Keto Diet Good for Athletes?

The impact of the ketogenic diet on athletic performance is not entirely clear. Some studies have indicated a decrease in fat mass and body weight without reducing muscle mass. However, whether that change in body composition has a positive effect on sports performance is not clear. Research is limited and mixed on the possible benefits of a keto and sports performance. Some research indicates that a keto diet may have some benefits in short durations of moderate to vigorous intensity exercise. However, other research does not indicate a positive impact.

According to an article in the Journal of Education, Health, and Sport, some studies have found that a keto diet may not significantly impact factors that may affect sports performance, such as HRmax, time to exhaustion, and VO2max. One thing is clear, further studies and research are needed to determine the effects of a ketogenic diet on athletes’ performance.


    A ketogenic diet involving high fat, moderate protein, and low carbohydrates may have some positive health benefits, such as promoting weight loss. But weight loss is often not a one-size-fits-all program. There are also possible risks associated with a keto diet, and it may not be appropriate for everyone. Although it may help reduce body fat without decreasing muscle mass, its impact on athletic performance also requires more study. The bottom line is that before making a significant shift in a diet, it is best to consult a doctor to determine the best plan.

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