Medical Nutrition Therapy For Heart Health

Overview

Maintaining strong heart health is crucial for longevity and general well-being. Besides exercise, which can strengthen the heart’s capability, nutrition is equally important to ensure a robust cardiovascular system. Nutritional components such as protein, carbohydrates, fats (cholesterol), and sugars all affect heart health in both positive and negative ways. 

Cardiovascular diseases account for up to 30% of deaths worldwide and are the leading cause of death in Western countries.¹ Heart conditions such as hypertension (high blood pressure), angina and atherosclerosis, along with diabetes and hypercholesterolaemia (high cholesterol) can all be heavily affected by nutritional intake. Therefore, it is imperative to understand the nutritional factors that affect heart health to prevent complications. 

Understanding heart health

The heart is a fist-sized organ with the main physiological function of pumping deoxygenated blood into the lungs and then pumping oxygenated blood around the body.² It is connected by an intricate system of vessels such as arteries, capillaries, and veins that help support the heart’s function of maintaining the cardiovascular system. 

Key factors 

There are multiple factors affecting the heart’s overall condition. Factors that cannot be controlled are considered non-modifiable risk factors, such as:

Gender

Whilst people assigned male at birth (AMAB) are more prone to cardiovascular conditions, people assigned female at birth (AFAB) have greater mortality and morbidity rates with the same cardiovascular conditions.³ 

Ethnicity

In terms of ethnicity, South Asians are most likely to have cardiovascular-related conditions.⁴ 

Genetics

Genetic predispositions that run in families such as familial hypercholesterolaemia (FH, high cholesterol) can increase your risk of cardiovascular disease. This is because individuals with FH have higher levels of low-density lipoprotein (LDL) cholesterol, also commonly known as the “bad cholesterol”.

Higher levels of LDL cholesterol are generally associated with an increased risk of coronary artery disease and heart attack.⁵ According to the Centers for Disease Control and Prevention (CDC), 1 in 250 people inherit FH. This genetic disorder also makes you more susceptible to developing cardiovascular disease at a younger age.⁶

Factors that can be controlled and changed by an individual are considered modifiable risk factors, which include:

• Exercise
• Diet
• Smoking
• Stress 

With consistent exercise, the heart muscle strengthens like any other muscle, which improves the ability to pump blood around the body and maintain high oxygen levels in the muscles. Moreover, exercise can contribute to decreasing the chances of a plaque build-up that can block the vessels which would eventually lead to poor blood flow and higher chances of a heart attack.⁷ 

The likelihood of having a stroke doubles in smokers. Smokers also have a higher chance of developing aneurysms, coronary artery disease, peripheral arterial disease, and other cardiovascular conditions. This is because cigarettes contain toxic chemicals which cause significant damage to your heart and blood vessels. This damage increases the chance of plaque formation and inflammation of the vessels.⁸ 

Diet contributes significantly to the overall health of the body. A diet with poor nutrition intake can directly lead to conditions such as atherosclerosis and high blood pressure. High blood pressure can cause a high force of blood flow inside the blood vessels, leading to damage to arteries and arterial walls over time. Furthermore, having a poor diet accompanied by a low level of activity and pre-existing genetic dispositions can lead to obesity and diabetes, which will also strain the heart’s health.

Basics of medical nutrition therapy (MNT)

Medical Nutrition Therapy or MNT is an evidence-based therapeutic management that relies on nutrition for the treatment/prevention of a disease. It can be given as a sole form of treatment or in combination with other treatment modalities to achieve optimal results. MNT involves a multidisciplinary team including a primary care physician and a dietician. 

By controlling and understanding the benefits of various foods, nutrition can be used to strengthen the heart’s condition. Evidence through literature has shown cardioprotective benefits from nutritional control and consideration.⁹

Dietary guidelines for heart health

A balanced and healthy diet is fundamental for maintaining overall well-being and preventing cardiovascular diseases. Several key factors of adopting a cardioprotective approach include:

• Blood pressure management
• Weight management
• Lowering cholesterol levels
• Reducing inflammation
• Improvement of overall well-being

Recommended nutrients and food choices

High fibre foods

Fibre is a carbohydrate that is indigestible by the body but provides benefits, such as the regulation of blood sugars and promoting a healthy digestive system. Fibre comes in two forms:

Insoluble fibre

• Can not be broken down and dissolved by water
• Helps to regulate the digestive tract and the movement of food in the digestive system
• Found in whole wheat products (e.g., quinoa, kale, almonds, and plums)

Soluble fibre

• Can be broken down and dissolved by water
• Helps to regulate blood sugars 
• Found in oatmeal, apples, blueberries, and lentils 

A study involving populations of the USA and Europe showcased that increased fibre content in a diet decreased cardiovascular-related conditions by 10 to 30%.¹⁰ The study reported a high-fibre diet involving fruits, vegetables, and oatmeal could decrease cholesterol levels, reduce inflammation, and help regulate blood pressure. 

Lean proteins

Protein is an essential nutrient for your muscles, hair, skin, nails, and general well-being. Most of the protein that the human body needs comes from animal sources, such as meats, eggs, and fish. But there are also plant-based sources of protein, such as tofu and nuts. Each protein source has its own characteristics that can affect heart health differently. 

Animal-based protein sources, such as beef, pork, mutton, and chicken contain relatively large amounts of protein per gram. However, they also contain a large amount of saturated fats. Too much accumulation of these fats can lead to increased levels of cholesterol. Whereas, plant-based protein sources contain a lower amount of protein per gram and saturated fats. 

According to the British Heart Foundation, adults are recommended 0.75 grams of protein per kilo of body weight per day (approximately 45 grams for AFAB and 55 grams for AMAB). A mixture of both animal and plant-based sources should also be consumed. To maintain the lowest concentration of saturated fats, leaner forms of proteins should be considered which include:

• Turkey
• Chicken
• Beans and legumes
• Lean ground beef
• Low-fat milk
• Salmon

Healthy fats

Many different types of fats are essential for a healthy body and heart as they provide various functions, such as helping the absorption of vitamins and providing adequate energy. The main types include polyunsaturated, monounsaturated, saturated, and trans fats. Polyunsaturated and monounsaturated are considered the “good” and healthy fats while saturated and trans are the “bad” fats.

According to the British Heart Foundation, adults AMAB should have less than 30 grams of fat per day, whereas those AFAB should have less than 20 grams of fat.

Foods high in unhealthy fats are derived from both animal and plant-based sources. They may include:

• Butter
• Lard
• Processed meats (e.g., sausages and bacon)
• Some plant-based oils (e.g., palm and coconut oil)

Healthy fats are primarily derived from plant sources including almonds, cashews, and peanuts, but are also found in animal sources such as salmon and mackerel.

Fruits and vegetables

Fruits and vegetables are abundant in nutritious components such as vitamins and fibre while being low in calorie count. 

According to a systematic review published in the International Journal of Epidemiology, a higher intake of fruits and vegetables correlated with lower cardiovascular conditions and diseases.¹¹

The recommended dietary portion of fruits and vegetables according to the World Health Organization is at least 5 servings a day.¹² Fruits and vegetables that are beneficial for heart health include:

• Kiwis
• Oranges
• Cantaloupes
• Broccoli
• Red peppers
• Carrots
• Sweet potatoes

Specific dietary approaches

Everyone has specific requirements and preferences due to variations in weight, height, and activity level. Different foods can cause a change in the body's characteristics in managing cholesterol levels, blood pressure or other cardiovascular-related conditions. Therefore, a personalised MNT plan should be tailored to fit your specific needs, by discussing with your healthcare professional. 

Dietary approaches to stop hypertension (DASH)

Individuals who have a higher risk or already have a cardiovascular condition may be recommended to undertake a DASH diet. The DASH plan is a flexible and easy-to-follow dietary regimen that does not require any specific foods. 

The DASH plan's main methodology goes by the calorie requirement of each individual but reduces foods that are more prone to affect heart health, such as foods high in “bad” fats and sodium. It also involves increasing your intake of cardioprotective foods, such as fruits, vegetables, and lean proteins. 

Mediterranean diet

The Mediterranean diet is another popular diet regimen used by people who have cardiovascular-related issues or just for weight loss. The emphasis of this diet plan is a more nutrient-rich diet, by consuming foods, such as fruits, vegetables, fish, and low-fat dairy. 

Research studies have shown a Mediterranean diet can strengthen cardiovascular health, and a personalised nutritional plan should be considered depending on the individual's characteristics and preferences.¹³

Monitoring and evaluation

Dietary management is crucial for heart health and dietary reflection needs to be considered regularly. If an individual has a higher risk of developing cardiovascular conditions, MNT should be considered with regular reviews and adjustments to the plan to ensure adherence. 

Summary

A healthy heart is essential not only for a healthy body but also for the mind. Your heart health can be strengthened by taking various preventative measures, such as exercising more and having a heart-healthy diet. Medical nutrition therapy (MNT) is a cornerstone of management for improving and preventing cardiovascular diseases.

A heart-healthy diet consists of lean proteins, high-fibre foods, healthy fats, and fruit and vegetables. Each individual should consult their healthcare professional to help them devise a personalised MNT plan suited to their specific needs.

Personalised diet plans are beneficial for helping you maintain and improve your heart health for the long term. Incorporating cardioprotective foods into your diet can help reduce your risk of cardiovascular disease and improve your overall health and well-being.