Is the Keto Diet Healthy? Pros and Cons of the Ketogenic Diet

Benefits of the Ketogenic Diet

The ketogenic diet is growing in popularity. Its origins date back to the early 20th century, when it was used to treat epilepsy. Today, it’s often chosen by people looking to lose weight—but not only that. It’s also of interest to patients seeking ways to improve metabolic health, manage diabetes, enhance cognitive function, or boost energy levels.

Its main principle—restricting carbohydrates in favor of fats—shifts the body’s energy source to ketones, leading to a unique metabolic state called ketosis. Although this dietary approach is somewhat controversial, it can offer a variety of health benefits.

What are the proven benefits of the ketogenic diet according to scientific research?

• Weight loss

• Improved glycemic control

• Treatment or alleviation of neurological conditions

• Improved lipid profile

• Increased energy and better focus

Weight Loss

One of the main reasons for the keto diet’s popularity is its effectiveness in weight loss. Due to reduced carbohydrate intake and increased fat consumption, the body starts burning stored fat as its primary fuel source. Additionally, ketosis suppresses appetite by modulating hunger hormones like ghrelin and leptin, which may help with calorie control.

Improved Glycemic Control

The ketogenic diet can be particularly beneficial for individuals with type 2 diabetes or insulin resistance. Reducing carbohydrate intake helps minimize blood glucose fluctuations and lowers insulin requirements, aiding in blood sugar stabilization.

Treatment or Alleviation of Neurological Conditions

The keto diet has long been used in the treatment of drug-resistant epilepsy, especially in children. Recent studies suggest it may also benefit other neurological disorders, such as Alzheimer’s, Parkinson’s disease, or multiple sclerosis. This effect is attributed to the neuroprotective properties of ketone bodies.

Improved Lipid Profile

Although the ketogenic diet is high in fats, some studies indicate that it can improve lipid profiles by lowering triglyceride levels and increasing HDL (“good”) cholesterol. This is largely due to reduced carbohydrate intake, which limits fat synthesis in the body.

Increased Energy and Better Focus

After adapting to the keto diet, many people report improved focus, steadier energy levels, and reduced post-meal fatigue. This may be due to the consistent energy supply provided by ketone bodies, as opposed to the glucose spikes caused by carbohydrate consumption.

Drawbacks of the Ketogenic Diet

Despite its many health benefits, the ketogenic diet also carries some significant limitations and risks. These stem from its restrictive nature and the major shift in macronutrient distribution. Such changes can affect the body in ways that aren’t always beneficial—especially over the long term.

Before adopting this dietary approach, consider its potential drawbacks. Without proper guidance, the keto diet can negatively impact your health and well-being.

What are the disadvantages of the ketogenic diet?

• Difficulty meeting nutritional needs

• Cardiovascular risks

• Limitations for athletes

• Excessive saturated fat intake

• Digestive issues

• Social and cultural limitations

Difficulty Meeting Nutritional Needs

Cutting out or significantly reducing entire food groups—such as fruits, starchy vegetables, and whole grains—can lead to nutrient deficiencies. This is especially true for vitamin C, vitamin D, magnesium, calcium, and potassium. Long-term keto dieting often requires supplementation.

Cardiovascular Risks

Although some people experience improved lipid profiles, others may see a rise in LDL (“bad”) cholesterol. The keto diet can increase the risk of cardiovascular diseases, especially when it includes large amounts of saturated fats from sources like red meat and butter.

Limitations for Athletes

In endurance sports such as marathons or long-distance cycling, glycogen stored in muscles and the liver serves as a key energy source. The keto diet, with its very low carbohydrate content, significantly reduces glycogen stores.

This can impair athletic performance during intense training or competitions, as the body cannot extract energy from fats as quickly or efficiently as it can from carbohydrates.

Excessive Saturated Fat Intake

Due to its high-fat nature, the keto diet often leads to excessive intake of saturated fatty acids, especially from animal products like meat, butter, and full-fat dairy. Overconsumption of these fats can promote inflammation and is associated with chronic diseases such as heart disease, type 2 diabetes, and even certain cancers.

“Keto Flu”

In the early stages of the keto diet, many people experience “keto flu”—a set of symptoms including fatigue, headaches, nausea, dizziness, and trouble concentrating. These symptoms are caused by the body adapting to new energy sources and the loss of electrolytes. Although they usually pass after a few days, they can be quite unpleasant.

Digestive Issues

Lower fiber intake—due to reduced consumption of whole grains, fruits, and vegetables—can lead to constipation. Over time, lack of fiber may also negatively affect gut microbiota.

Social and Cultural Limitations

The ketogenic diet can be difficult to maintain long-term due to the need for strict control over food choices. Social situations like dining out, family gatherings, or parties can be challenging for someone on keto.

Who Should Consider the Keto Diet?

The ketogenic diet can be effective in managing and treating certain health conditions. It is generally recommended in the following cases:

• Drug-resistant epilepsy – especially in children

• Type 2 diabetes – for improved blood sugar control and insulin sensitivity

• Overweight and obesity – particularly when other diets have failed

• Hypertriglyceridemia – when high triglycerides are due to carbohydrate metabolism disorders

Who Should Avoid the Keto Diet?

The ketogenic diet is not suitable for everyone. It should not be used by:

• People with liver disease – as the liver is key to producing ketones, and compromised liver function may not support keto metabolism

• People with pancreatic diseases – such as acute or chronic pancreatitis, cysts, or gallstones affecting the pancreas

• People with congenital metabolic disorders – such as primary carnitine deficiency, porphyria, or pyruvate kinase deficiency

Is the Keto Diet Healthy?

It’s hard to give a definitive answer as to whether the ketogenic diet is healthy. It largely depends on an individual’s health context and how the diet is implemented.

This diet can be beneficial for treating certain medical conditions and may support weight loss in the short term. However, long-term adherence to a high-fat, low-carb diet carries some risks—and in some cases, it is strictly contraindicated.

If you’re considering trying the keto diet, it’s best to first consult a medical professional or clinical dietitian. An expert can advise whether this approach is right for you or whether it might pose unnecessary health risks.

Keep in mind that following the ketogenic diet requires strong willpower and self-discipline. It comes with many restrictions, and even small deviations may compromise your results. If you’re unsure what to eat on keto, try a keto meal plan from Peater. The meals, designed by experienced dietitians, are nutritionally balanced to help you avoid deficiencies.

Good luck!

References:

• Khalid, K., Apparow, S., Mushaddik, I. L., Anuar, A., Rizvi, S. A., & Habib, A. (2023). Effects of Ketogenic Diet on Reproductive Hormones in Women With Polycystic Ovary Syndrome. Journal of the Endocrine Society, 7(10), bvad112.

• Dowis, K., & Banga, S. (2021). The Potential Health Benefits of the Ketogenic Diet: A Narrative Review. Nutrients, 13(5), 1654.

• Batch, J. T., Lamsal, S. P., Adkins, M., Sultan, S., & Ramirez, M. N. (2020). Advantages and Disadvantages of the Ketogenic Diet: A Review Article. Cureus, 12(8), e9639.

• Muscogiuri, G., Barrea, L., Laudisio, D., Pugliese, G., Salzano, C., Savastano, S., & Colao, A. (2019). The management of very low-calorie ketogenic diet in obesity outpatient clinic: a practical guide. Journal of Translational Medicine, 17(1), 356.