Last updated date: 23-Apr-2023
Medically Reviewed By
Medically reviewed by
Dr. Lavrinenko Oleg
Medically reviewed by
Dr. Hakkou Karima
Originally Written in English
Does Ketogenic Diet affect Cholesterol?
Obesity is a serious global health risk, with adult death rates as high as 2.8 million per year. Obesity, which is typically the result of an unhealthy lifestyle and bad eating habits, is linked to the majority of chronic illnesses such as diabetes, hypertension, and heart disease. Appropriately designed food regimes for weight loss can aid in the management of the increase in obesity.
A extremely low-carbohydrate and high-fat ketogenic diet has been shown to be particularly effective for fast weight reduction. The ketogenic diet is a low-carbohydrate, high-fat, adequate-protein diet that is used to treat children with difficult-to-control (refractory) epilepsy. Low-carbohydrate and ketogenic diets are quite popular across the world.
Ketogenic diets are gaining popularity again. Nutritional ketosis is generally achieved by limiting carbohydrate consumption to less than 20–50 g per day, however there are exceptions. The low carbohydrate intake of these diets is generally compensated for by a high fat content, whereas protein is reasonable. As a result, the term “low-carbohydrate high-fat” (LCHF) is more suitable under isocaloric settings.
Ketogenic Diet Ingredients
A ketogenic diet is high in fats, moderate in protein, and low in carbs. The macronutrients in the diet are approximately divided into three categories: 55-60% fat, 30-35% protein, and 5%-10% carbs.
A ketogenic diet comprises a variety of fats. Saturated fats from oils (palm, coconut), lard, butter, and cocoa butter are suggested in large amounts. However, certain healthy unsaturated fats are allowed on the keto diet, such as avocados, nuts (almonds, walnuts), and olive oil. Here's a quick summary:
- Saturated Fats: butter, lard and coconut oil
- Trans Fats: they are chemically changed and become hydrogenated to be preserved such as margarine .however, all hydrogenated fats should be avoided.
- Monounsaturated Fats: olive and avocado
- Saturated and monounsaturated fats: like Butter, almonds, avocado, egg yolks, and coconut oil
People who benefit from Keto diet
- In general, a keto diet is healthful, safe, and acceptable for the majority of people, however further study into the long-term consequences is required .
- If you have renal illness, liver disease, familial hypercholesterolemia (high cholesterol levels inherited from family), or fat-induced lipemia, the keto diet is probably not the best idea for you.
- Before starting a keto diet, see a nutritionist if you have type 1 diabetes, gallbladder problems, or a genetic disorder that affects fat metabolism.
Aside from its well-documented weight-loss advantages, recent research has revealed that ketogenic LCHF diets have a positive influence on cardiovascular risk factors. However, the high consumption of saturated fatty acids and low intake of dietary fiber in LCHF diets may at the beginning, raise the low-density lipoprotein (LDL) cholesterol, which is a risk factor for coronary heart disease.
Furthermore, epidemiological results indicate a particular function for small, dense LDL particles in the genesis of atherosclerosis. Recent meta-analyses, however, have failed to reach an consensus on the connection between dietary saturated fat and the risk of cardiovascular disease (CVD). As a result, there is conflicting evidence about LCHF diets and cardiovascular health.
Evidence behind the Ketogenic Diet
- Carbohydrates, which range from 200 to 350 grams per day, make up around 55 percent of the normal American diet in terms of overall calorie consumption.
- Until recently, the huge potential for carbohydrates to produce negative consequences was largely ignored. A higher sugar intake is linked to a 44 percent higher frequency of metabolic syndrome and obesity, as well as a 26 percent higher chance of developing diabetes mellitus.
- In a 2012 analysis of all cardiometabolic mortality (heart disease, stroke, and type 2 diabetes) in the United States, inadequate intakes of 10 dietary variables were linked to 45.4 percent of deaths.
The highest rate of expected mortality was linked to:
- High sodium intake (9.5%), followed by
- Low intake of nuts and seeds (8.5%)
- High intake of processed meats (8.2%)
- Low intake of omega-3 fats (7.8%)
- Low intake of vegetables 7.6%)
- Low intake of fruits (7.5%)
- High intake of artificially sweetened beverages (7.4%).
- The lowest estimated mortality was associated with
- Low polyunsaturated fats (2.3%) and
- Unprocessed red meats (0.4%).
How are Ketone bodies formed?
- Carbohydrates are the body's major source of energy generation. Insulin secretion is considerably decreased and the body enters a catabolic condition when the body is deprived of carbs owing to a reduction in consumption to less than 50g per day. As glycogen reserves decrease, the body is forced to undergo specific metabolic adjustments. When the body's glucose stores are depleted, two metabolic processes come into action: Ketogenesis and gluconeogenesis.
- Gluconeogenesis is the body's endogenous synthesis of glucose; however, when glucose availability decreases, endogenous glucose production cannot keep up with the body's demands, and ketogenesis jumps in to provide an alternative source of energy in the form of ketone bodies. Ketone bodies replace glucose as a primary source of energy.
- Fatty acids are broken down into acetoacetate, which is then transformed into beta-hydroxybutyrate and acetone. These are the fundamental ketone molecules that build in the body when a ketogenic diet is followed for an extended period of time. "Nutritional ketosis" is the name given to this metabolic condition.
- The body's metabolism remains in a ketotic condition as long as carbs are not consumed. The nutritional ketosis state is thought to be relatively safe since ketone bodies are generated in modest quantities with no changes in blood pH. It is quite different from ketoacidosis, a potentially fatal disease in which ketone bodies are generated in excessively high amounts, changing blood pH to an acidotic state.
- Ketone bodies produced in the body may be easily used for energy generation by the heart, muscular tissue, and kidneys. Ketone bodies can also pass the blood-brain barrier, providing an additional source of energy to the brain. Because of a lack of mitochondria and the enzyme diaphorase, RBCs and the liver do not use ketones.
- This diet causes the patient's body to burn fat instead of carbs. This diet's goal is to get more calories from protein and fat. Consuming less carbs in one's diet helps lower triglycerides since one consumes fewer calories than usual.
- Ketone bodies produce more adenosine triphosphate in comparison to glucose, sometimes aptly called a "super fuel."
- Ketone body production depends on several factors such as:
- Resting basal metabolic rate (BMR)
- Body mass index (BMI)
- Body fat percentage.
A ketogenic diet may be followed for a minimum of 2 to 3 weeks up to 6 to 12 months. Close monitoring of renal functions while on a ketogenic diet is imperative, and the transition from a ketogenic diet to a standard diet should be gradual and well controlled.
Health benefits of Ketogenic diet
- A short-term ketogenic diet, as well as a long-term ketogenic diet, have been shown to reduce body weight and BMI in individuals who follow this diet in several trials. A ketogenic diet also improves lipid profiles and lowers cardiovascular risk factors including hypertension. There was also a drop in triglycerides, LDL cholesterol, and blood glucose levels, as well as an increase in HDL cholesterol.
- Obesity, type 2 diabetes, and metabolic syndrome have all been proven to benefit from a ketogenic diet. Due to the brain-protecting effect of ketosis, which results in fewer seizure occurrences, this diet is occasionally advised for uncontrolled epilepsy.
- Although the ketogenic diet is considerably superior at inducing weight reduction in otherwise healthy obese people, and the resulting weight loss is quick, intense, and sustained for at least two years, the understanding of the clinical effects, safety, tolerability, effectiveness, treatment duration, and prognosis after diet cessation is difficult, and more researchs are needed to understand disease-specific processes.
- In addition, the ketogenic diet has shown promise in a number of neurological diseases, including epilepsy, dementia, ALS, traumatic brain injury, acne, malignancies, and metabolic disorders, according to numerous research.
Keto diet effect on obese people
- In obese people, insulin resistance is a possible detrimental consequence, however some studies have found increases in insulin sensitivity.
- Nevertheless, many people considering such diets are overweight or obese at the outset, and even a small weight loss may be biologically advantageous to them. However, it is necessary to maintain body weight after losing weight, which is typically a big issue.
- More research is needed to better understand the impact of long-term KD usage on metabolic disorders and cardiovascular risk factors, as well as to better identify which dietary macronutrient composition is best.
Adverse Effects of ketogenic diet
- The ketogenic diet's most frequent and mild short-term adverse effects are a set of symptoms known as keto flu, which include:
- In a few days to a few weeks, these symptoms will go away. Some of these symptoms might be alleviated by ensuring appropriate hydration and electrolyte consumption.
- While the ketogenic diet may aid weight loss in the short term, it is not sustainable in the long run. Furthermore, several studies demonstrate that the diet is linked to a slew of issues that frequently result in emergency department visits and hospitalizations for dehydration, electrolyte imbalances, and hypoglycemia.
Bad breath is also common
- Bad breath, which is typically characterized as fruity and somewhat sweet, is one of the most prevalent adverse symptoms of ketosis. Acetone, a ketone produced as a consequence of fat metabolism, is to cause. During ketosis, your blood acetone levels rise, and your body releases part of it through your breath.
- Sweat and urine can occasionally begin to smell like acetone. This strange-smelling breath will go away in a few weeks for the majority of people.
Ketosis may cause digestive problems
- Changes in diet can occasionally cause stomach problems. Constipation is a typical side effect of not eating enough fiber and not drinking enough water, which is also true for ketogenic diets. Diarrhea can occur in certain persons, although it is uncommon.
- If you convert to a keto diet and drastically modify your eating habits, you're more likely to experience digestive issues. However, stomach problems generally go away within a few weeks.
Other side effects of ketosis
Other, less common side effects may include:
- Kidney stones. Kidney stones have been reported in children with epilepsy who have been on a ketogenic diet. While on the diet, experts advise that you assess your kidney function on a frequent basis.
- Raised cholesterol levels. Some people get increased total and LDL (bad) cholesterol levels.
- Fatty liver. This may happen if you stick to this diet for a long period.
- Hypoglycemia. If you use medicines to control your blood sugar, talk to your doctor before starting the diet since your dose may need to be adjusted.
Effect of Ketogenic diet on Cholesterol
Lipoproteins are cholesterol transporters that assist transport cholesterol to and from body cells in the bloodstream. There are two types of lipoproteins.
- LDL- low-density lipoprotein (namely “bad” cholesterol) which may makes arterial narrowing worse
- HDL- High-density lipoprotein (namely “good” cholesterol) which promotes the protection of the body against narrowing blood vessels.
- According to a study published in the journal Obesity Biology and Integrated Physiology, ketogenic diets raise cholesterol and inflammatory markers linked to long term illness. During four weeks on an ordinary diet and subsequently on a ketogenic diet, specialists noticed changes in lipids and inflammation. While the patients were on the ketogenic diet, total cholesterol, LDL, ketones, and inflammatory indicators all increased significantly.
- The more fats you eat, the more likely you are to have a rise in LDL cholesterol, which leads to elevated cholesterol. According to the American Heart Association for Cardiovascular Diseases, total fats should not account for more than 30% of total calories. Consuming more than the suggested amounts is harmful to the body.
- Carbohydrate restriction and ketosis induction both reduce dyslipidemia, although the effects on total cholesterol and low-density lipoprotein cholesterol (LDL-C) are less predictable. LDL-C and total cholesterol levels usually stay close to baseline; however, some patients have seen a rise in LDL-C levels.
- The consumption of fat is higher with ketogenic diets, which may be hazardous to anybody if used for a long time. One new long-term research suggests it may be a risk factor for heart disease.
- Furthermore, the need for statin treatment in hyperlipidemia caused by a ketogenic diet is unclear. It's also unclear if age or concurrent activity while on a ketogenic diet play a role in the lipid levels changing.
- Close monitoring of individuals with a high risk of cardiovascular disease should be considered due to the unexpected response of LDL-C levels to a ketogenic diet. More research on cholesterol, BMI, and CPK levels as well as cardiovascular risks are required.
- KD has also been linked to a rise in the size and volume of LDL cholesterol particles, which is thought to lower cardiovascular risk by lowering atherogenicity.
- Another research found no significant change in total and LDL cholesterol levels after 12 months on a KD vs a regular diet, except after three months, when the conventional diet group's LDL cholesterol levels were lower!
- Interestingly, the effect of a KD on lipid profile may be related to ethnicity: white participants lost more weight and had a greater reduction in triglycerides levels than black subjects in one research. Total cholesterol, HDL cholesterol, and LDL cholesterol levels did not alter significantly in this research.
Rodents and Humans!
The effects of KD on lipid profiles in rats and humans are different. KD seems to be linked to higher levels of total, HDL, and LDL cholesterol, as well as triglycerides in rats. The opposite is true in humans. Differences in food composition, which are often greater in total fat but also in saturated fat in animal studies, account for the majority of these differences. Long-term research in rats and humans would be required to compare saturated fat with unsaturated fat KD.
Cautions and Contraindications
People with diabetes who use insulin or oral hypoglycemic medicines face severe hypoglycemia if their medications are not properly adjusted before beginning this diet. The ketogenic diet is not recommended for those who have pancreatitis, liver failure, fat metabolism problems, primary carnitine insufficiency, porphyrias, or pyruvate kinase deficiency.
People on a ketogenic diet are probably to have a false positive breath alcohol test. Because to ketonemia, acetone in the body can occasionally be converted to isopropanol by hepatic alcohol dehydrogenase, resulting in a false positive alcohol breath test result.
The effect of the ketogenic diet on protein
- A well-formulated ketogenic diet limits protein consumption to less than 1g/lb body weight, unless individuals are doing strenuous activity involving weight training, in which case protein intake can be raised to 1.5g/lb body weight. This is done to prevent the body from producing glucose endogenously through gluconeogenesis.
- It does not, however, limit fat or total daily calories. People who follow a ketogenic diet lose weight quickly, up to 10 pounds in two weeks or less. This diet has a diuretic impact, thus part of the first weight reduction is attributable to water weight loss, followed by fat loss. Surprisingly, lean body muscle is largely unaffected by this eating regimen. As a nutritional ketosis state is maintained, hunger sensations diminish, and an overall reduction in calorie intake aids in weight loss.
Because of the intricacy of the mechanism and the absence of long-term research, a general prescription of the ketogenic diet for the prevention of type 2 diabetes mellitus or cardiovascular disease may appear premature, but it is not farfetched for primary weight loss.
The ketogenic diet has become very popular
- It is not surprising that this diet has grown popular among healthy, normal-weight people. Follow-up data over the last 10-year period (until 2014) in a large Swedish population-based sample whose diet intake has been followed regularly in the same individuals reveal reduced carbohydrate and greater protein and fat intakes.
- Interestingly, current food survey data from Swedish female university students indicate that the observed national shift from carbohydrate to fat intake remains, at least among those interested in food and nutrition. Notably, males predominated in ketogenic LCHF diet treatments in healthy, normal-weight individuals that evaluated blood biomarkers for CVD.
Ketosis is healthy and safe, but is not suitable for everyone
- Some patients, such as those with obesity or type 2 diabetes, and children with epilepsy, may benefit from a ketogenic diet. However, it can produce certain adverse effects, such as the "low carb flu," leg cramps, foul breath, and digestive difficulties, particularly in the first few days or weeks.
- Experts also point out that, while the diet may help you lose weight in the short term, the weight may return once the diet is discontinued. Many people fail to keep to their diets.
- People considering starting a keto diet should first consult with a healthcare practitioner who can help them determine if it is a good option for them, as the keto diet may not be suitable for everyone. Some people gain significantly from a higher carb diet, while others feel and perform less well.
To sum up
Dyslipidemia is a well-known risk factor for heart disease. An increase in cholesterol levels is a long and steady process that finally blocks your arteries. Nonetheless, given our current lifestyle, we are more prone to it as a result of our increased consumption of fast food. More research is needed to determine the long-term effects of the keto diet on the body.
The ketogenic diet is typically healthy for the majority of individuals and can even assist decrease cholesterol levels in the longer term. Because KD is often heavy in fat, is possible impact on the lipid profile must be evaluated. Moreover, some people need to modify their keto diet to prevent increasing their cholesterol levels.
Medically Reviewed By
Medically reviewed by
Dr. Lavrinenko Oleg
Medically reviewed by
Dr. Hakkou Karima