Is KETO Diet Beneficial for Heart Patients? 

Introduction  

Heart disease is a leading cause of death globally. While medical treatment is the best way to manage it, lifestyle measures such as a balanced diet, physical activity, and stress management are essential for long-term benefits in patients with heart diseases¹.

A keto (ketogenic) diet is a high fat, moderate protein, and very low carbohydrate diet. The KETO diet is believed to have beneficial effects for weight loss, blood pressure and sugar levels, all of which can pose risk for heart diseases². Owing to this, some studies suggested that this diet could be beneficial for the heart, although further research has found otherwise, and its use in patients with heart diseases is still ambiguous¹. 

In this blog, we will discuss what is keto diet, its potential health benefits and risks, and try to give you a clear picture of how this diet affects the cardiovascular system.  

What is KETO Diet?

The keto diet is a diet that is high in fats and very low in carbohydrate content. The key concept of this diet is to drastically reduce the intake of carbs. It is believed that when you reduce the carbs intake and increase the intake of fats and proteins, the body starts utilising fat as its energy source, which helps with increased utilisation of fat reserves in the body, and can have various health benefit^2,3.   

A classic keto diet plan includes: 

• Fats: 80%–90% 
• Proteins: 6%–15% 
• Carbohydrates: 5%–10%¹ 

What to Eat on the Keto Diet 

Foods to include in the keto diet:  

• Protein: Eggs, meat and poultry 
• Dairy: Cream, cheese, buttery, and full-fat yogurt without sugar 
• Fats: Olive oil or coconut oil 
• Nuts and Seeds: Almonds and flax seeds 
• Fruits: Avocados, berries, strawberries, lemon and olives.  
• Low-carb vegetables: Green leafy vegetables, carrots, mushrooms, and tomatoes⁴.

Foods to avoid in the keto diet: 

• Legumes (lentils and chickpeas)  
• Starchy vegetables (high in carbs, eg- potatoes and peas) 
• Grains (pasta and rice) 
• Fruits (high in sugar)⁵ 

A diet that focuses on keto-friendly foods with 80 to 90% of fat intake is beneficial for encouraging the body to utilize fat as a source of fuel for body functions. 

How Does the Keto Diet Work? 

Your body produces energy from the glucose found in the carbohydrates that you eat. Now if you restrict your carbohydrate intake, there will be a severe shortage of glucose in the body for energy production. Our body, being a marvel, will always find a way to adapt. In this case, the alternate solution is to use the stored fat cells to produce energy as a fuel for body functions. So, the main principle of the keto diet is to shift the body’s primary fuel source from glucose (carbohydrates) to fats. Compared to glucose, fat cells can produce a lot more energy to meet the basic needs. When the carbohydrate intake is low, there a shift in the body’s metabolism. It starts utilizing fats and produces ketone bodies. These provide fuel for organs such as heart muscles, the brain, and kidneys for their functioning^1,2,3.

Is the Keto Diet Heart-Healthy? 

The keto diet plan may have some positive effects on your general health. Along with being a super-fuel for various organs, it can help with weight loss, improving blood sugar levels and lowering blood pressure for some¹. As improving these parameters can potentially benefit heart health, the keto diet was believed to be heart healthy⁶. But recent research suggests that these effects are usually short-term. This diet, which involves less amount of carb intake and very high amounts of fats, may eventually result in the rise of LDL (bad cholesterol), which increases the risk of blockage in arteries that can lead to heart attacks and strokes⁷. So, although the KETO diet has some short-term health benefits, its use in heart patients is questionable. Yet, if you are a heart patient and keen on trying out the keto diet, it must be done with careful consideration and under your doctor’s guidance for its safe use. 

Potential Benefits of the Keto Diet

Research studies suggest that the keto diet plan may have various health benefits. These include:  

• Weight Loss: The diet leads to utilisation of fat from the body, helping in weight reduction. Research suggests that the keto diet can potentially reduce weight more compared to glucose utilisation⁸.   

• Improved Blood Sugar Levels: Due to reduced intake of carbs, the body produces less sugar leading to reduced sugar levels in the blood⁹.

• Enhanced Insulin Sensitivity: The diet can help lower the body’s need for insulin, helping the cells respond better to it. This results in improved insulin sensitivity which is beneficial in lowering blood sugar levels and controlling conditions like metabolic syndrome and PCOD^9,10.

• Lowering of Blood Pressure (BP): Keto diet can help in lowering the blood pressure. Weight loss can reduce the BP. Improved insulin sensitivity also helps in clearance of sodium from the body, which in turn helps in lowering the BP¹.

• Reduced Hunger: The keto diet foods can restrict hunger-related hormones which are responsible for the feeling of hunger. Reduced hunger reduces food intake, which may help in controlling weight⁸.

• Management of Epilepsy: A ketogenic diet may help control seizures in some individuals with epilepsy. Studies have found a positive outcome with the use of this diet in management of epilepsy patients refractory to other treatments. Although it must always be discussed with your doctor and designed as per your needs¹¹.

• Beneficial for Neurodegenerative Disease: Animal and initial human studies have shown that the keto diet may Alzheimer, Parkinson, and amyotrophic lateral sclerosis. It may also prove to have positive effects in stroke, headaches and sleep disorders¹².

• Effect on Cholesterol Levels: The impact of the keto diet foods on the blood lipid profile is controversial. Although some studies have shown that the KETO diet can help lower total cholesterol and LDL levels, others reveal that these effects are mostly short-term and the high fat content in the diet can eventually increase the LDL levels, which can pose heart disease risk¹³. Further long-term studies are needed to clarify this. 

While initial studies have shown the potential health benefits of the keto diet, further large-scale human trials are needed to confirm these.  

Side Effects of the Keto Diet 

Some common side effects may occur when starting the keto diet, known as “keto-flu”. When carbohydrate intake is limited and glycogen stores are exhausted, the body rapidly excretes salt and water, causing these symptoms. These include the following:  

• Fatigue 
• Headache 
• Dizziness 
• Nausea 
• Vomiting 
• Constipation 
• Lower tolerance for exercise¹⁰ 

Usually, these symptoms relieve on their own as the body adjusts, but increasing sodium intake may help. If you notice any of these, its best to consult your doctor. 

Who Should Avoid Keto? 

If you have any of the following conditions, you should avoid the keto diet: 

• Heart disease (Irregular heart rhythm, dyslipidaemia, recent stroke or heart attack) 
• Liver disease 
• Kidney disease 
• Type 1 diabetes 
• Pregnant or Breastfeeding 
• Cancer 
• Serious infection¹⁴ 

It is better to avoid the keto diet foods or discuss with your doctor if you have any of the above-mentioned conditions, as they may potentially worsen your condition. 

Risks for Heart Patients

If you have already experienced a heart attack or other heart conditions, you are at risk of developing some medical issues with the keto diet that may worsen your condition or cause additional symptoms:  

• Nutritional Deficiencies: You may be at a risk of developing mineral deficiencies with the keto diet foods, which can affect your heart function¹⁵.
• Kidney disease: Increased amount of protein can result in overloading the kidneys, which can be dangerous for the heart¹⁵.
• Electrolyte disturbances: You may get dehydrated and experience symptoms such as irregular heartbeats (cardiac arrythmias) due to an imbalance in your electrolyte levels¹⁶. 
• Liver disease: Keto diet increases liver enzymes, which can result in the development of non-alcoholic fatty liver disease (NAFLD)¹⁵.
• Diabetic Ketoacidosis: Heart patients with diabetes are at a risk of developing this condition due to the excessive production of ketone bodies as the body switches from glucose to fat as a source of energy. When the ketone body levels increase beyond limit, it can be dangerous and lead to conditions like coma¹³.
• Medication interactions: The severe carbohydrate limits of the diet may cause people to eat more leafy greens which are rich in Vitamin K. This can interfere with the anti-clotting medication warfarin used by heart patients. Additionally, SGLT-2 inhibitors, which are medications used to treat heart failure and diabetes, might not work well with a ketogenic diet¹³.

So, although the keto diet is popular for its perceived benefits, if you have experienced any signs or symptoms related to any heart conditions, you need to be cautious. It is best to discuss with your cardiologist before adopting the keto diet or any other diet routinely. 

Safe Ways to Follow Keto 

Considering the risks involved with a keto diet plan, you can follow some tips to be safe and avoid potential issues. These include:  

1. Following your doctor’s advice

If you wish to start the keto diet plan, it is best to discuss properly with your doctor first and understand if it’s safe for you. Especially if you have any medical condition, it is important to go for regular visits while following the diet to keep a track of your health status with the diet¹⁰.

2. Going for nutritional counselling

This can help you learn about nutrient-rich foods and proper eating habits that support your goals, and help you understand what is keto diet and its impact on the health¹⁷.

3. Opting for a balanced and sustainable diet plan

The best diet plan is the one that is easy to prepare and avail, includes a balance of all macro and micronutrients and is planned according to your taste and health needs. You can consult with a dietitian to know what to eat on keto diet and design a plan based on your needs. 

4. Being prepared for initial discomfort

Certain individuals may experience side effects like constipation, fatigue, or headaches, when initiating a keto diet. It’s important to be aware of these and selecting your diet mindfully¹⁰.

5. Staying hydrated

Drinking plenty of water may help with avoiding dehydration and electrolyte imbalances with the diet¹⁸.

6. Choosing heart-healthy foods

Opt for fats with more saturated fats like avocados, olive oil, and fish oil, and avoid those with unsaturated fats. Choose whole foods, millets, fresh fruits, seasonal vegetables, and leans proteins such as fish, eggs, and poultry¹⁹.

7. Checking your cholesterol levels regularly

Monitoring your cholesterol levels regularly, especially the LDL values, can help a check on the impact of the diet on the cardiovascular health. 

8. Cutting down on added salt and sugar

A general rule that should be followed is to limit salt and sugar intake. Avoid fried, packaged and processed food.  

9. Planning your meals in advance

It is important to know what keep your shopping list handy. It ensures that you have the right foods in your hands for making healthier choices. Choose freshly prepared, home cooked meals. This allows control on quantity and quality of ingredients used. 

Discussing with the doctor and devising a diet plan suitable as per your medical condition is fore and foremost when you plan to switch to a keto diet. To derive the maximum benefits and avoid side effects, always follow your doctor’s advice. 

Alternative Heart-Healthy Diets 

A keto diet for heart patients may prove to be safe and effective if you follow the above-mentioned recommendations, although there are other diets too that may be more suitable, especially for heart patients. These include: 

• Mediterranean Diet: Focus on healthy fats (olive oil, nuts, fatty fish), whole grains, vegetables, and lean proteins) 
• DASH diet: Focus on fruits, vegetables, lean proteins, and low-fat dairy 
• Plant-based diet: Rich in fiber, antioxidants, and healthy fats from fruits, vegetables, legumes, nuts, and whole grains, reducing cholesterol and heart disease risk^17,19.

These heart-healthy diets can be more beneficial for individuals with heart diseases. Although, it is advisable to consult your doctor before starting any diet to ensure it aligns with your requirements. 

Conclusion 

The keto diet is high in fat, moderate protein, and a very low carbs diet where the body utilises fat cells for energy production instead of glucose. This process may show benefits such as weight loss and improvement in blood sugar and blood pressure regulation in some cases. Some of these may be beneficial for the heart, but the impact of this diet on the blood lipid levels may be deleterious. Therefore, the diet needs to be carefully considered in patients with heart disease, and if followed, should always be under their doctor’s guidance. Alternate diets such as the DASH or Mediterranean diets can prove to be better options for them. 

Frequently Asked Questions (FAQs)

References

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