Does Keto Work? Here’s What Science Says about the Keto Diet

author avatar Dr. Eric Berg 10/16/2023

Millions of people have adopted a ketogenic diet to achieve weight loss, improve their metabolic health, and lower their risk of heart disease. But does keto work? 

Yes, keto works—and research confirms that a high-fat, low-carbohydrate diet promotes a healthy body weight, increases energy, enhances cognition, and is linked to a lower risk of chronic diseases.

Discover the science behind the ketogenic diet and learn why keto may be the key to longevity. 

Woman behind a table with keto-friendly foods

What is keto?

The ketogenic diet is a low-carbohydrate, moderate-protein, and high-fat diet that pushes your metabolism to burn fat instead of carbohydrates for energy. 

As your liver breaks down fat, it generates large quantities of ketone bodies, which are organic acids that act as highly efficient energy sources. When ketones start to build up in your circulation and begin to fuel your body, you enter a metabolic state known as ketosis.

In fact, your brain, heart, and muscle cells prefer ketones as a fuel source compared to relying on sugars and carbohydrates for energy. 

Insulin—a key metabolic hormone that controls blood sugar levels and regulates how your body produces energy—is released in response to dietary carbs and sugars. High insulin levels stimulate fat storage and block your metabolism from burning body fat as a fuel source.

Limiting carbohydrate intake to no more than 20 to 50 grams of net carbs daily and obtaining most of your calories from healthy fats keeps insulin levels low, which stimulates fat burning and triggers ketosis.

Critics often point out that keto is a restrictive diet that increases the risk of nutrient deficiencies. That’s why it’s essential to do Healthy Keto®, a holistic high-fat diet that combines the metabolic benefits of ketosis with balanced nutrition. 

By focusing on non-GMO organic vegetables, pasture-raised eggs, full-fat organic dairy, grass-fed beef, game meats, and wild-caught fish, Healthy Keto provides the nutrients needed for optimal health while burning fat.

Watch the video below to learn how to get started with keto!

Keto diet for beginners - how to start

Does keto work?

Yes, research supports that the keto diet works. It’s a safe and highly effective eating plan that improves metabolic health, promotes hormonal balance, enhances cognitive function, and increases energy levels.

Although it may seem counterintuitive, a high-fat diet makes losing weight easy by preventing blood sugar and insulin spikes, the main culprits of weight gain, insulin resistance, and diabetes.

In addition, ketosis triggers profound metabolic changes linked to reduced hunger and cravings, making keto a sustainable diet that’s easy to follow long-term.

Because keto works and is sustainable, it’s generally more successful than other low-carb diets, such as the carnivore diet, or meal plans focusing on calorie intake, such as Weight Watchers. 


There is a common misconception that keto causes high cholesterol levels due to an increased consumption of saturated fats. 

However, this claim has long been refuted, and a recent study published in Progress in Cardiovascular Disease found that saturated fat doesn’t elevate low-density lipoprotein, also known as LDL cholesterol, linked to an increased risk of heart disease.

The study found that a high-carb intake, not saturated fat, is linked to elevated cholesterol and cardiovascular disease, which explains why a ketogenic diet can lower cholesterol levels and promote heart health. 

Nutrition science illustration

What does science say about keto's effectiveness?

The ketogenic diet was initially developed during the 1920s to treat epilepsy and has helped many people manage seizures and other neurological symptoms. 

Doctors noticed that patients who followed ketogenic diets generally had better metabolic health and a lower risk of obesity, metabolic syndrome, high blood pressure, and diabetes. 

Since then, countless studies have investigated the effectiveness and safety of a high-fat diet, and evidence consistently reports the metabolic, hormonal, and neurological benefits of the ketogenic diet.

Research published in Nature reviewed a large number of studies and summarized that the ketogenic diet is linked to various impressive health improvements, including:

  • Weight loss   

  • Improved blood sugar control 

  • Potent anti-inflammatory effects 

  • Improved blood lipid markers

  • Lower LDL cholesterol 

  • Enhanced neurological health 

  • Suppressed hunger and cravings  

  • Diverse microbiome 

  • Lower risk of neurodegenerative diseases 

  • Potential to increase longevity  

Keto-friendly foods

Eight science-backed benefits of keto

Diet and nutrition-related science can be challenging to conduct and often gives rise to conflicting outcomes. 

However, research findings on the ketogenic diet are clear and consistent and have been confirmed repeatedly. 

Here are eight science-backed benefits of keto.

1. Weight loss

Keto is a popular weight-loss strategy—and for a good reason.

Ketosis promotes fat burning, which allows your body to convert stored body fat into energy, which typically is accompanied by rapid weight loss.

While some critics suggest that weight loss on keto is caused by a reduced caloric intake and not a result of carbohydrate restriction, this notion has long been debunked. 

A two-year trial published in The New England Journal of Medicine compared weight loss on a low-carb, low-fat, and Mediterranean diet and found that the low-carb diet resulted in the most significant weight loss and reduction of waist circumference.

Interestingly, participants in the low-fat and Mediterranean diet groups were asked to limit daily caloric intake to 1500 for men and 1300 for women, whereas the low-carb group had no caloric restriction. 

This shows that weight loss on keto isn’t due to a caloric deficit but a result of metabolic changes in response to limiting carbohydrates and sugars.

Not only is keto an incredibly effective weight-loss tool, but it also supports long-term weight management by raising your basal metabolic rate (BMR), the number of calories your body needs to perform basic functions while at rest. 

Research published in The American Journal of Clinical Nutrition found that individuals on a high-fat diet have a higher BMR compared to those on a high-carb diet. 

Fat burning requires more energy than utilizing carbs as a fuel source, which explains why a high-fat diet increases BMR and supports a healthy body weight.

Metabolic rate illustration

2. Metabolic health 

Metabolic imbalances such as elevated blood sugar, belly fat, insulin resistance, and high blood pressure are the primary risk factors for serious health conditions, including diabetes, obesity, metabolic syndrome, and heart disease.

The ketogenic diet is one of the most effective dietary tools to prevent or restore metabolic imbalances and helps significantly lower the risk of chronic diseases.   

A study published in Lipids compared the metabolic effects of a low-carb diet and a calorie-restricted diet and concluded, “Subjects following the carbohydrate-restricted diet had consistently reduced glucose and insulin concentrations, insulin sensitivity, weight loss, and decreased adiposity compared to the calorie-restricted group.”

This suggests that counting calories isn’t helpful for weight loss and highlights the detrimental role of dietary carbs on metabolic health.

Keto is gaining increasingly more attention regarding the prevention and treatment of type 2 diabetes (T2D).  

Research published in Diabetes found that almost 60 percent of T2D patients who followed a 12-week ketogenic diet plan were able to reduce and even eliminate medication use to maintain normal blood sugar levels.

A similar but significantly longer clinical trial published in Nutrition and Metabolism found that long-term adherence to a low-carb diet is associated with weight loss and significant improvements in HbA1c, a measurement of average blood sugar levels and indicator of metabolic health, in individuals with T2D. 

3. Hormonal balance

Reducing carbohydrate intake helps keep insulin levels balanced, which is crucial in maintaining the body’s hormonal balance.

Elevated insulin levels can stimulate the ovaries to produce testosterone and lead to hormonal imbalances linked to polycystic ovary syndrome (PCOS), fertility problems, acne, and menstrual issues. 

Most women with PCOS have some degree of elevated insulin, also known as hyperinsulinemia, and the ketogenic diet offers an effective strategy to restore hormone balance and alleviate PCOS symptoms.  

A recent study published in the Journal of Translational Medicine investigated the effect of a 12-week ketogenic diet in overweight women with PCOS. 

All participants had significantly lower blood sugar and insulin levels and markedly improved sex hormone balance. The authors concluded, "The ketogenic diet may be considered a valuable non-pharmacological treatment for PCOS.”

Watch the video below to learn how the ketogenic diet supports hormonal balance in women.  

Keto hormone balance

4. Cardiovascular Health 

Metabolic and cardiovascular health are closely linked, and it’s well established that a metabolically healthy body is less likely to develop heart disease.

Research published in Obesity found that low-carb, high-fat diets consistently improve cardiovascular health markers, including lower blood lipid and LDL cholesterol levels, enhanced insulin signaling, and increased levels of heart-healthy high-density lipoprotein (HDL) cholesterol.

These findings have been replicated and confirmed by several studies, including a clinical trial published in The Journal of Clinical Endocrinology and Metabolism, which suggests that keto doesn’t cause adverse cardiovascular effects and, in fact, is associated with an improved cardiovascular health profile. 

In addition, the ketogenic diet may play a critical role in mitigating cardiovascular disease risk in individuals with elevated cholesterol.  

This study published in Molecular and Cellular Biochemistry found that the ketogenic diet is a safe long-term diet that promotes healthy cholesterol levels and lowers the overall risk of heart disease. 

5. Cognitive and neurological health 

Many people who start keto report improved focus, memory, and mental clarity

Ketones are a more efficient energy source for the central nervous system than carbs and sugars, and ketosis has been found to promote neurological functions and brain health.

Research published in Cell Metabolism reports that the ketogenic diet induces profound metabolic pathways and gene expressions that improve memory function and lower the risk of cognitive decline.

Another study in Scientific Reports found that a high-fat diet increases nitric oxide. This potent vasodilator improves vascular circulation within the brain and is linked to a lower risk of age-related cognitive decline and neurodegenerative diseases, including Alzheimer's and dementia.

It’s important to note that these studies were conducted in mice as research on the impact of long-term dietary patterns on cognitive function in later life is time-consuming and challenging.

However, these findings do provide valuable insight into the potential benefits of the ketogenic diet for cognitive and neurological health

6. Liver health 

Non-alcoholic fatty liver disease (NAFLD) is typically linked to a high-carb diet and can have serious health consequences.   

Ketosis stimulates the production of enzymes that speed up the breakdown of fatty acid accumulations in the liver, which explains why keto is an excellent choice for individuals with poor liver function or fatty liver disease. 

A randomized controlled trial published in The Journal of Hepatology found that a low-carb, high-fat diet is significantly more effective in treating NAFLD compared to standard treatments.

Combining intermittent fasting with keto can maximize the benefits of a low-carb diet for liver health and can help reduce liver fat drastically.   

Watch the video below to learn how a low-carb diet helps reduce liver fat by up to 50 percent in 14 days.   

Reduce liver fat

7. Diverse intestinal microflora 

Increasingly more research is conducted to establish how the ketogenic diet influences the intestinal microflora. 

A healthy microbiome helps regulate immune responses, nutrient absorption, and inflammation, and evidence suggests that an imbalanced microflora increases the risk of autoimmune diseases such as multiple sclerosis, rheumatoid arthritis, and Hashimoto’s thyroiditis.  

Individuals with autoimmune diseases often lack adequate levels of beneficial microbes, and a study published in Frontiers in Microbiology found that the ketogenic diet significantly improved gut bacteria diversity in patients with multiple sclerosis. 

These findings may explain why a high-fat diet has been found to lower the risk of autoimmune diseases and may help improve autoimmune-related symptoms.

8. Longevity 

The ketogenic diet is linked to improved metabolic, cardiovascular, neurological, and hormonal health, and its role in longevity is of increasing interest to the scientific community.

Although more long-term human studies are needed to confirm the link between keto and lifespan, there is evidence that keto may extend longevity.

A study published in Cell Metabolism reports that mice fed a ketogenic diet had a significantly longer lifespan and survival rate than those fed a standard diet. 

It’s believed that ketosis activates genes and biochemical pathways that preserve and prolong physiological functions and lowers the risk of cancer, a predominant cause of premature death and shorter lifespan.  

Ketones and glucose road sign

Key takeaways

Does keto work? Yes! Research agrees that a low-carb, high-fat diet benefits metabolism, promotes cardiovascular health, supports brain function, and promotes hormone balance.

Science confirms that a ketogenic diet is highly effective for managing metabolic imbalances such as type 2 diabetes, insulin resistance, and obesity and may even help extend your lifespan. 


1. Is keto backed by science?

The ketogenic diet has been extensively studied, and evidence consistently suggests that a low-carb, high-fat diet improves metabolic health, lowers the risk of heart and liver disease, promotes hormonal balance, and supports cognitive functions. 

2. Is keto healthy?

A nutritious low-carb diet like Healthy Keto® is an ideal meal plan to achieve a healthy weight, support brain health and hormonal balance, and lower the risk of cardiovascular disease, insulin resistance, and diabetes.

Many people following the keto diet report increased energy levels, mental clarity, better sleep, and overall improved health and well-being.

3. What does science say about keto’s effectiveness?

Science confirms keto is a highly effective tool for preventing or managing insulin resistance, diabetes, obesity, elevated cholesterol, non-alcoholic fatty liver disease, and PCOS.

Research also suggests that a high-fat diet reduces hunger and cravings, which makes the keto diet a sustainable long-term tool to improve health, maintain a healthy weight, lower the risk of chronic diseases, and potentially increase longevity.  

4. What are the benefits of keto?

Ketosis triggers profound metabolic changes that are linked to various impressive health benefits, including weight loss, improved blood sugar and lipid levels, enhanced neurological function, and a lower risk of chronic diseases and cancer.  

5. Does keto really work?

Yes, keto does really work. Research consistently shows that a low-carb, high-fat diet leads to greater weight loss, better cholesterol and blood lipid levels, and significantly better metabolic health than low-fat or calorie-restricted diets.  

6. How long does it take to lose weight on keto?

Most people experience noticeable weight loss of up to 10 pounds within the first two weeks of keto due to glycogen shedding and water loss. 

Once your body becomes keto-adapted, losing between one to two pounds per week isn’t uncommon.  

7. What are the risks of doing keto?

During the initial phase of keto, some individuals experience symptoms known as keto flu, which can include fatigue, headache, nausea, and irritability. 

These symptoms can typically be managed with electrolytes and disappear when your body becomes adapted to utilizing fat as a primary fuel source. 

It’s also important to do Healthy Keto, a nutritious low-carb diet focusing on whole foods and non-GMO organic produce, to avoid nutrient deficiencies.  

8. Can anyone do keto?

The ketogenic diet is generally considered safe and well-tolerated by most people and has been found especially beneficial for obese individuals and those with type 2 diabetes, fatty liver disease, PCOS, metabolic syndrome, and elevated cholesterol levels.

However, individuals with eating disorders and those taking medications that impact fat metabolism should consult a healthcare provider before starting a ketogenic diet to minimize the risk of side effects.


9. Is keto sustainable?

Ketosis suppresses hunger and cravings, and evidence suggests that keto dieters can lose a significant amount of weight without developing cravings or hunger, which makes keto a viable and sustainable long-term dietary approach.  


  1. A Novel Intervention Including Individualized Nutritional Recommendations Reduces Hemoglobin A1c Level, Medication Use, and Weight in Type 2 Diabetes

  2. Ketogenic Diet Reduces Midlife Mortality and Improves Memory in Aging Mice

  3. A ketogenic diet extends longevity and healthspan in adult mice

  4. Effects of a ketogenic diet in overweight women with polycystic ovary syndrome

  5. Ketogenic diet enhances neurovascular function with altered gut microbiome in young healthy mice

  6. Reduced Mass and Diversity of the Colonic Microbiome in Patients with Multiple Sclerosis and Their Improvement with Ketogenic Diet

  7. A randomized trial comparing a very low carbohydrate diet and a calorie-restricted low fat diet on body weight and cardiovascular risk factors in healthy women

  8. Weight Loss with a Low-Carbohydrate, Mediterranean, or Low-Fat Diet

  9. Gluconeogenesis and energy expenditure after a high-protein, carbohydrate-free diet

  10. Cardiovascular and Hormonal Aspects of Very-Low-Carbohydrate Ketogenic Diets

  11. Carbohydrate Restriction has a More Favorable Impact on the Metabolic Syndrome than a Low Fat Diet

  12. Long Term Effects of Ketogenic Diet in Obese Subjects with High Cholesterol Level

  13. Low-carbohydrate diet in type 2 diabetes: stable improvement of bodyweight and glycemic contr ol during 44 months follow-up

  14. Treatment of NAFLD with intermittent calorie restriction or low-carb high-fat diet – a randomized controlled trial


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