Ketogenic, keto, or the so-called the high-fat, low-carb diet has become a weight loss trend in the recent years.
Many people choose this diet with the hope to quickly reduce their weight and instantly lose a few pounds. However, like every other diet that strictly excludes certain foods, keto diet can be related to various health risks in the long run.
This article will briefly explain what keto diet is and how it affects the body. Besides, it will guide you through the groups of people that may benefit from this diet, as well as those who may experience adverse effects.
Let’s dive in!
What is keto diet?
Ketogenic, or keto diet focuses on consumption of foods that are high in fats, low in carbs, and moderate in protein.
According to Harvard School of Public Health, fats consumed on keto diet should account for about 70-75% of the total daily calorie intake, while proteins should be 20-25% and carbs 5-10%. [1] Or in other words, people who are on ketogenic diet expect to lose weight while eating mainly foods high in fat.
In fact, the mechanism of ketogenic diet is very complex, as it triggers unusual body processes.
The minimal carb intake keeps the blood sugar levels low and prevents spikes in blood glucose. However, when you eat very little amounts of carbs for a few days (keepin in mind that carbs break down to glucose i the body), the risk of hypoglycemia (too low blood sugar) increases. In order to avoid the potential health risks of hypoglycemia, the body enters in “rescue mode” and starts creating “ketons”. Those are basically water-soluble compounds made from the breakdown of fats that give the body energy to function properly. [2]
Ketons can give the body about 70% of the energy it needs. [3] The other 30% of energy come from the liver, which uses amino acids, glycerol, pyruvate, and lactate to create extra fuel for the body. [4]
This way, keto diet enables the body to use energy and function properly without the consumption of glucose ( e.g., in the form of carbs).
Is keto diet for everyone?
As already mentioned, ketogenic diet triggers unusual body processes like ketogenis (creation of ketons). This way, if you are on keto diet for a long time, the regular body functions, related to insulin production, use of blood glucose, metabolisation of fats, and others, may cause both beneficial and unwanted health effects, depending on your overall health condition and predisposition to certain diseases.
For that reason, keto diet is not a “one size fits all” solution for weight loss. It’s important to consult your healthcare provider or a registered dietitian if you want to “go keto” and follow his/her recommendations and dietary guidelines.
Who is keto diet good for?
Various medical studies and research papers have looked into the health benefits of keto diet. Below, you can find what individuals may benefit from being on ketogenic diet:
Epilepsy patients
According to the Epilepsy Foundation, keto diet may help with reduction of seizures in people with epilepsy who don’t respond to seizure-controlling medications. That being said, the source mentions that various studies have found that around 50% of children who start ketogenic diet may reduce their seizures by at least 50%. What is more, 10-15% of epileptic children may stop experiencing seizures due to their keto dietary regime. [5]
However, patients with epilepsy have to strictly follow the dietary advice of their doctor and adopt ketogenic diet only if it’s prescribed by their healthcare provider.
People with episodic or chronic migraine
A 2017 study published in the journal of “Neurological Sciences” suggests that keto diet may positively affect individuals who suffer from episodic and chronic migraine by reducing the severity of their symptoms. [6] However, the source mentions that more research is needed to identify why and how keto diet may improve migraine symptoms.
Type 2 diabetes patients
According to a 2008 study published in the Journal of Nutrition and Metabolism, keto diet (and other diets low-carb diets) can help type 2 diabetes patients to improve their glycemic control (prevent spikes in blood sugar levels), and, as a result, take sugar-controlling medicines less frequently. [7]
Based on this source, the Global Diabetes Community suggests that keto diet can help type 2 diebetes patients to become less reliant on diabetes medication. [8]
Cancer patients
A 2020 review paper published in the Journal of Molecular Metabolism has looked into the potential effects of ketogenic diet on cancer patients. The source presents medical evidence that keto diet may support and improve the efficacy of chemo– and radiotherapies for tumor treatment, as well as improve overall quality of life of cancer patients. [9]
Yet, the review paper emphasises on the need for more studies and research in order to recommend keto diet as part of a complex anti-cancer therapy.
Overweight or obese individuals
According to a 2019 review paper published in the journal of Clinical Nutrition and Metabolic Care, keto diet can effectively help obese and overweight individuals to lose weight, improve lipid profile and insulin sensitivity, while supporting their energy levels for physical activity. However, the review shows that ketogenic diet is not yet evidenced to support long term weight loss effects. [10]
People with prediabetes and insulin resistance
Insulin resistance is a prediabetic health condition, that is characterized by damaged ability of the body cells to recognise insulin and to use blood glucose for energy. Therefore, people with insulin resistance often support abnormally high insulin production or have high blood sugar levels. [11]
That being said, eating minimal amounts of carbs can help the body to prevent sharp spikes in blood sugar levels, and various medical papers suggest that it can potentially improve the quality of life of insulin resistant patients and and even reverse prediabetic condition and insulin resistance. [12]
However, a 2018 study in the American Journal of Physiology evidenced that long term keto diet can actually lead to insulin resistance in mice due to increased lipid oxidation and lower respiratory exchange ratio. [13] Even though this study does not present evidence based on human trials, it may present important implications regarding the effect of low-carb high-fat diet on human health and supports further studies on the topic.
Who should avoid keto diet?
Even though the ketogenic diet may have many health benefits, there are various groups of people who are at risk of health complications after adopting this diet. That being said, it’s important to have a consultation with your healthcare provider or dietitian before going keto.
Pregnant women
Evidence suggests that following ketogenic diet during pregnancy may negatively affect the embryo (and later the baby). The damage that keto diet may cause is related to physical changes like larger heart, smaller brain, smaller cervical spinal cord, and others. [14]
Type 1 diabetes patients
Even though keto diet may improve metabolic control, there is no evidence that it can slow the progression or prevent type 1 diabetes. Besides, there is no definite scientific evidence that keto diet is safe for (type 1) diabetic patients , and insulin dependent individuals. [15]
People suffering from pancreatic disease
Evidence suggests that ketogenic diet may often cause hypertriglyceridemia due to the high intake of fats. That being said, this health condition is a prerequisite for the development of acute pancreatitis. [16] Based on those findings, keto diet may increase the risk of pancreatitis complications.
Liver disease patients
A 2020 study published in the Cureus Journal of Medical Science suggests that ketogenic diet may increase the risk of developing hyperlipidemia (your blood has too much cholesterol, triglycerides, or other types of fats), as well as elevated liver enzymes and liver disease. [17]
Individuals with chronic diseases, malnutrition, surgeries
Ketogenic diet is a restrictive diet which is not based on macronutrient balance and diversity. That being said, individuals who suffer from chronic health conditions (or have a medical history with such health issues), micronutrient deficiencies, hormonal imbalances, as well as those who have undergone surgical procedures should be very careful if/when following keto diet. In those cases, this diet should be approved, recommended, and strictly supervised by licensed health practitioner or physician to avoid negative health effects.