The keto diet, described as a low-carb, high-fat diet, is currently being applied and promoted for weight loss. However, consultant cardiologist Associate Professor Naylin Bissessor warns that the fact is that the high-fat component effectively suppresses appetite and leads to satiety.
The danger of the high-fat diet, however, is a concomitant increase in LDL cholesterol, which in layman’s terms is described as the “bad cholesterol”. LDL cholesterol, when oxidised in the body, is a fatty globule that combines with inflammatory cells called macrophages that form coronary artery plaques.
These high-risk plaques form in the wall of the coronary artery and later calcify. In patients with established coronary artery disease, the accumulation of high-risk plaques can cause heart attacks and blockages that require bypass surgery or stents.
Coronary plaques may also rupture, causing a blood clot, resulting in sudden cardiac death or cardiac arrest as a first presentation with significantly unpleasant outcomes.
As a consequence, there is a purposeful (and responsible, one might say) drive to keep LDL cholesterol low in patients who have proven coronary artery disease on angiography (demonstrating inflammation of the endothelium - the lining of the coronary arteries).
Keto diets like Keto 800, Banting, and Atkins, for example, which are all high in saturated fats, cause an immediate rise in LDL cholesterol.
In patients with coronary artery disease, the high LDL with inflammation in the lining of the coronary arteries causes these plaques to grow rapidly, especially amongst people with bad genetics, diabetes, ex-smokers, high blood pressure, and high LDL cholesterol.
The hidden cost of high-fat satiety
Proponents of the Keto 800 and Atkins diet themselves are known to have been victims of sudden cardiac deaths, chronic coronary artery disease, and cardiac arrest, which would probably have been caused by the rupture of coronary plaques, causing a blood clot (coronary thrombosis), leading to a fatal arrhythmia.
Whether these unfortunate incidents were all directly attributable to diet is not public knowledge.
Medical practitioners recommending these diets must understand that the keto high-fat (butter, bacon, animal fat, cheese, etc.) diets are not suitable for cardiac patients, and there are known challenges and potentially fatal downsides.
A spike in younger cardiac patients
In cardiology practice, there has been a significant upswing in the number of younger patients having bypass surgery, heart attacks, and stents. The common factor in many cases is being on and/or having been on these keto diets. This includes diabetics who have previously had minor coronary artery disease on angiography.
The recommended diet, especially for people with a known predisposition to cardiac illness, is the Mediterranean diet, which has, over the years, produced in my experience the best outcomes in cardiac patients.
The Keto diet may indeed improve blood sugars in diabetics and induce weight loss, but it can also lead to extensive coronary artery disease with the consequential medical challenges.
The medical duty to screen first
As a practising cardiologist with many years of experience in this field, I want to express my concern about GPs, physicians, and dietitians who are recommending keto diets to diabetic patients without checking their cardiac histories.
Screening of such patients for coronary artery disease is crucial before a recommendation is made and is ethically and professionally appropriate to take this step before making any recommendations or giving advice. To do otherwise is simply irresponsible.
The Mediterranean diet does not recommend processed carbohydrates. Rather, fresh fruit, nuts, vegetables, fish, and chicken (white meat), and salad are the food of choice. The Mediterranean diet also allows 1-2 glasses of red wine once a day with a meal. However, if alcohol leads to irresponsible food consumption, then it should be avoided.
The combination of the Mediterranean diet and exercise is strongly recommended for “at-risk” future cardiac patients.
A typical Mediterranean diet is explained in my free module on Cardiobis.com, my education website for coronary disease prevention and rehabilitation. Cardiac patients at risk are expected primarily to do exercise and eat a heart-healthy Mediterranean diet.
A local blueprint for heart health
Recent studies on the benefits of fish oil (omega-3 fatty acids) have resulted in several medications containing fish oil extracts being produced at high costs. The Cape snoek, however, is rich in omega-3 fatty acids, which strengthen the internal coronary artery endothelial linings and prevent LDL oxidation.
Fruit and green vegetables also have important antioxidants. The famous wines of the Cape, its vegetables and fruit, and the readily available Cape snoek could provide the answer to a heart-healthy lifestyle.
Exercise has been a hallmark of the Cape fitness culture. There are world-class events and opportunities like the cycling and running competitions, which highly motivate the fitness enthusiast.
My advice for cardiac patients at risk of a heart attack is to adopt the Cape lifestyle version of the Mediterranean diet. This includes Cape snoek and a glass of wine with clean, fresh produce. As the old adage goes, prevention is always better than cure.
Enrol and go to the local gym regularly, and engage a personal trainer to keep you motivated and assess your body stats. Be actively involved in endurance fitness, dancing, cycling, jogging, and swimming that the Cape offers.
Most importantly for all the cardiac-conscious, avoid the dangerous keto high-fat diets as a rule. This is what I tell my cardiac patients in Australia.
Cape Town offers the ideal version of the Mediterranean diet and exercising lifestyle for the cardiac patient. This is the heart-healthy lifestyle that we should all embrace.
****Associate Professor Naylin Bissessor (MBChB, PhD, FRACP, ECFMG) is a consultant cardiologist based in Melbourne, Australia, and the founder of Cardiobis. He writes in his personal capacity. His expertise extends to the assessment and management of coronary artery disease at the highest scientific level in international medical practice.****
**The views expressed do not necessarily reflect the views of the National Media Group.**