Low-carb, high-fat ketogenic diets have been a topic of discussion for some time now. People who follow this type of diet are known to experience a range of benefits, such as weight loss, improved blood sugar control, and reduced inflammation. However, recent headlines claiming that a keto-like diet can increase the risk of cardiovascular disease have left many people feeling confused and concerned. In this article, Dr.Boz will unpack one of the studies that was the source of these headlines, as well as discuss the importance of properly measuring ketosis.
The Study: An Observational Analysis
The American College of Cardiology recently published a study that examined the association between low-carb, high-fat(Keto-Like) diets and cardiovascular disease. The study was observational, meaning that it observed participants over time and collected data on their dietary habits and health outcomes. The study was conducted in the UK and has yet to be peer-reviewed or published.
The study analyzed data from approximately 300 individuals who completed a questionnaire about their dietary habits over the last 24 hours. The participants reported consuming less than 25% of their calories from carbohydrates, which they self-reported as being on a ketogenic diet. The study then looked at the participants' cholesterol levels and incidence of cardiovascular events, comparing those who reported being on a keto-like diet to those who did not.
The Flaw in the Study's Definition of Keto
One of the biggest flaws in the study's methodology is its definition of a ketogenic diet. In the medical community, being on a ketogenic diet means that the body is in a state of nutritional ketosis, where it is burning fat for fuel instead of carbohydrates. This ketosis state is achieved by limiting carbohydrate intake to a certain threshold, usually around 20-50 grams per day.
However, in the study, the participants were only asked about their dietary habits over the last 24 hours, and those who reported consuming less than 25% of their calories from carbohydrates were classified as being on a ketogenic diet. This is problematic because it is impossible to determine if these individuals were actually in a state of nutritional ketosis. In fact, it is highly unlikely that they were, given that most people need to limit their carbohydrate intake to 20 grams or less per day to achieve ketosis.
The Study's Findings
Despite the flawed definition of a ketogenic diet used in the study, the researchers still found that those who reported being on a keto-like diet had a higher incidence of cardiovascular events and higher cholesterol levels compared to those who did not. This is what led to the scary headlines about keto diets increasing the risk of heart disease.
However, it is important to note that the study's findings should be taken with a grain of salt. Firstly, the study was observational, which means that it cannot prove causation, only association. Secondly, the study's definition of a ketogenic diet was flawed, so it is unclear if the participants were actually in a state of nutritional ketosis.
The Importance of Measuring Ketosis
The flawed definition of a ketogenic diet used in the study highlights the importance of properly measuring ketosis. In order to know if someone is truly in a state of nutritional ketosis, their ketone levels must be measured. This can be done through blood, urine, or breath testing.
It is important to note that even small variations in carbohydrate intake can affect ketone levels. Therefore, it is important to monitor ketone levels regularly and adjust dietary intake accordingly to maintain a state of ketosis. Simply reducing carbohydrate intake without measuring ketones is not enough to be considered on a ketogenic diet.