What is the keto diet?
The keto diet is an eating plan that is very low in carbohydrates, moderate in protein, and rich in fat.
By restricting your intake of carbohydrates, your body begins a process called ketosis, where stored fat is broken down into ketone bodies and released into the bloodstream. These ketone bodies are then used as a source of energy instead of carbohydrates.
Why is it popular?
Advocated by celebrities, best-selling authors, and widely shared on social media, the diet has gained quite the reputation over the years with claims that it can treat a variety of different ailments.
However, the main reason why most people go on the keto diet is to lose weight. As fat is being broken down for energy instead of carbohydrates, the body burns more fat than it gains, leading to weight loss.
Is the keto diet healthy for your heart?
In theory, the keto diet can benefit the heart. However, there are many versions of the diet, which may lead to some people following an unhealthy high fat diet without triggering ketosis. The diet can also be difficult to follow in practice. Some may opt for too much protein and unhealthy fats as they turn to processed food as a main food source in the diet. In addition, it is important to note that there are no long-term studies on the keto diet in relation to risk for medical conditions such as heart attacks and stroke.
Nonetheless, when followed correctly, the keto diet may offer the following health benefits for your heart.
People with type-2 diabetes need to be careful with the amount of carbohydrates they consume as they have a higher risk of developing heart disease. For diabetics, blood-sugar spikes can damage the blood vessels and nerves in the heart. Therefore, without proper management, diabetes may lead to serious heart diseases.
The keto diet has been associated with lower blood glucose, decreased insulin resistance, decreased hunger and cravings, weight loss, decreased triglycerides, and increased HDL (High-density lipoprotein cholesterol). Hence, the diet may be beneficial for preventing the onset of diabetes. However, bear in mind that most of these benefits were observed from short-term studies, and there is no long-term research analysing the effects of the diet.
During ketosis, there is a build-up of acids called ketones within the body, which may put additional stress on your kidneys. Hence, those with type 1 diabetes may not be suitable for the keto diet, as people with this condition are commonly found to have renal impairment.
If you have diabetes and intend to start on the keto diet, discuss this with your doctor to see if the diet is appropriate for your condition. Due to a lower carbohydrate intake, people with diabetes may experience hypoglycemia if they don’t make appropriate changes to their diabetes medication.
Obesity is associated with a higher risk of heart diseases. Hence, managing your weight with any effective diet can help prevent heart diseases in the future.
According to research conducted with overweight individuals, a 5 – 10% reduction in weight may lead to a lower risk of developing cardiovascular disease. Lose even more weight, and the risk factors for heart disease are further reduced.
The nature of the keto diet allows one to lose weight in different ways. Firstly, the diet targets the body’s fat stores and breaks it down to create energy. As you keep to the diet, your body will use up more fat than it stores, which naturally leads to weight loss. The protein and fat recommended in the diet also help you feel fuller as compared to the same volume of carbohydrates. This is because protein and fat dampen hunger-stimulating hormones. As a result, you are less likely to overeat, which also helps you lose weight.
Improve overall heart health
Based on the results of short-term studies, the keto diet appears to have potential benefits for heart health through weight reduction and reduced insulin resistance. That said, there have not been any long-term studies that confirm this.
Some studies have found that when starting the keto diet, people experience a significant change in their cholesterol levels. In some people, levels of bad cholesterol (LDL and triglycerides) can go up quite significantly. In others, it can go down. It is not clear how these changes in cholesterol impact the long-term risk of heart problems.
It is important to understand that the positive effects of the diet on your heart can only come about if you eat healthy and nutritionally balanced meals. The keto diet may work to help lower LDL for some people, but it may not be the best diet for some individuals with high blood cholesterol. If you have high blood cholesterol, it is recommended to check with your doctor before starting on the keto diet.
What about people with existing heart conditions?
For those with existing heart conditions, caution should be practised when starting a new diet, including the keto diet. While it appears to be safe in the short-term, research on the long-term effects of the diet is lacking.
Additionally, if you have medical conditions involving your pancreas, liver, thyroid or gallbladder, you should avoid the diet completely as there can be dire consequences to your health.
If you are unsure if you are suitable for the keto diet, consider seeking dietary advice from a dietitian. If you have a pre-existing heart condition or a history of high cholesterol, consult a cardiologist before commencing on the keto diet.
Article reviewed by
Dr Michael MacDonald, cardiologist at Mount Elizabeth Hospitals
Grace Yanni Yanti, senior dietitian at Mount Elizabeth Hospitals
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