Cardiovascular diseases

Cardiovascular diseases (CVDs) are a group of disorders affecting the heart and blood vessels. Many types of cardiovascular diseases can be summarised into 4 main types :

1. Coronary artery disease - a disorder of blood vessels supplying the heart muscle
2. Cerebrovascular disease - a disorder of blood vessels supplying to the brain
3. Peripheral artery disease - a disorder of blood vessels supplying to arms and legs
4. Others such as congenital heart disease, infective and valvular heart disease, and cancer

According to the World Health Organization (WHO), cardiovascular diseases are the leading cause of global death. An estimated 17.9 million people died from CVDs reported in 2019 which represents one-third of all global deaths. 85% of these deaths are due to heart attack and stroke.¹

Risk factors of cardiovascular diseases

The exact cause of CVD remains unclear. However, some factors will increase the risk of developing the disease which either can be controlled (modifiable) or cannot be controlled (non-modifiable).^2,3

Non-modifiable risk factors

• Age (65 years old and older)
• Gender
• Ethnicity
• Family History

Modifiable risk factors

• High cholesterol levels and diabetes

Both high cholesterol and diabetes could accelerate atherosclerosis.^2,4,5,6,7 

• What is atherosclerosis?

Picture 1. Atherosclerotic Formation Process in Blood Vessels

Source: Centers for Disease Control and Prevention⁴

Atherosclerosis is a condition in which blood vessels become thick and hard due to the progressive formation of fatty plaques within the inner layer of blood vessels. The fat deposit in the blood vessel will gradually narrow the space of affected vessels, thus blocking the blood flow through the affected area (Picture 1).

Hyperlipidemia is a condition in which your blood contains a lot of bad cholesterol. Cholesterol is a type of fat that is important to our bodies. There are two types of cholesterol: LDL (low-density lipoprotein) and HDL (high-density lipoprotein). Known as “bad” cholesterol, LDL is a key risk of cardiovascular diseases because of its natural character to form fatty plaques in the arteries. On the contrary, HDL, the “good” cholesterol, gives a protective effect to blood vessels where it counterattacks the LDL by removing excess cholesterol from arterial walls.^8,9

Diabetes is a condition in which your pancreas cannot produce enough insulin, an important enzyme that helps to convert glucose that we eat into energy. This process is also progressive and gradually will cause sugar to build up in the blood. In diabetic patients, blood is thicker than normal, thus the blood is prone to aggregate and form a clot within the vessel’s wall.^8,9 Diabetes is also one of the risk factors that could increase the risk of high cholesterol levels in our blood.

The Centers for Disease Control and Prevention (CDC) reports that adults with high cholesterol and diabetes are twice as likely to develop cardiovascular diseases compared to normal healthy adults.^3,9

• High Blood Pressure

High blood pressure is the major risk of developing cardiovascular diseases. Normal blood pressure is 120/80mmHg. Blood pressure is called high when it reaches 140/90mmHg and above.

When the pressure is too high, it damages the lining of arterial and other blood vessel walls, causing them to be more susceptible to the build-up of plaque. Furthermore, the high pressure causes plaque formed in larger vessels to rupture and move to smaller vessels, and results in the blocking of these small vessels. This sudden blockage underlies various CVD emergency conditions such as heart attack and stroke.

• Behavioural risk factors

Behavioural risk factors that contribute to the development of CVDs according to WHO are:¹⁰

• Unhealthy diet
• Sedentary lifestyles
• Tobacco use
• Harmful consumption of alcohol

Our bodies are smart. They have a system that regulates and uses the substances that are needed, as well as discards any waste products that are not needed through urine, faeces, and sweat. Problems come when our bodies can not “digest” an excessive intake of substances or toxic materials, hence left unprocessed and becoming harmful inside our bodies. These harmful waste products will lead to many health problems, including heart diseases.

Living in a fast and busy world, instant food has become the first choice in food selection. As we know fast food, processed meat, sweets, and sugary drinks are unhealthy as they contain high saturated fat (rich in bad cholesterol), sodium, and sugars that could lead to an increase in cholesterol levels, blood pressure, and blood glucose respectively. On top of that, an unhealthy diet and inactive physical activity could lead to obesity which has become a source of many health conditions. Hence, regular exercise such as walking, running, swimming, etc. is also important. Physical activities such as sports allow our bodies to burn excessive fat and glucose stored in our bodies and convert them to energy.

Moreover, tobacco use is another habit that should be taken seriously. Many researches prove the use of tobacco increases the risk of hyperlipidemia (rise in bad cholesterol level) by killing the good cholesterol, which makes the blood thicker and sticker, and damages the lining of blood vessels wall, making them easy to rupture.⁹ Cessation of tobacco use could lower the risk of developing atherosclerosis by suppressing all the above conditions.

Symptoms of cardiovascular diseases

Symptoms of cardiovascular diseases vary, depending on the severity of the diseases. It is important to note that most of the underlying risk factors, which are hyperlipidemia (high cholesterol level) and hypertension (high blood pressure) cause no symptoms. Thus, they are called as the “silent killer”

In short, symptoms of cardiovascular diseases include:⁷

• Chest pain (angina)
• Shortness of breath (dyspnea) on exertion or rest
• Dizziness or fainting
• Fatigue or exhaustion

Chest pain (angina) is the most unique symptom of CVDs that is usually described as pressure on the chest. In the most severe cases, someone will describe them as “an elephant standing on my chest”. Depending on the severity of the disease, some people will experience shortness of breath when they climb stairs, walk, or even rest. Other symptoms that might develop on CVDs are swelling legs, excessive sweating, and numbness on one side of the face and extremities (arms and legs).

Benefits of star fruit for heart health

Star fruit (Averrhoa carambola) is a tropical fruit, native to the South-East Asian Region. Just like its name, the fruit has a five-point star shape with a sweet and tangy flavour and the sweetness of the fruit should be enjoyed as fresh fruit or juice. Star fruit can be processed in many ways depending on its ripeness and as the fruit ripens, the acidity lessens. Moreover, young star fruit has a very sour and fresh taste which can be perfect to make the base of sour fish soup. 

Star fruit is well-known for its delicious taste and has numerous health benefits that have been known for centuries. All these benefits are extracted from the fruits, leaves, roots, and flowers that have been used traditionally as a natural remedy. Some of the medicinal properties for heart health include¹¹ :

Hypoglycemic and antidiabetic effects

Each star fruit is rich in fiber and low in calories which may aid in controlling blood sugar and cholesterol. The soluble fibers that enter our stomach will form a gel-like structure which slows down the gastric emptying process. Thus, the amount of food passing from the stomach to the intestine will decrease and less glucose is absorbed. The lesser the amount of glucose absorbed, the lesser the concentration of glucose in the blood. 

Hypocholesterolemic effects

The digestion process of glucose might also affect levels of blood cholesterol. As the concentration of blood glucose decreases, the formation of LDL (“bad” cholesterol) also decreases. Another reason why fibers could lower cholesterol levels is that as the amount of blood glucose decreases, the body still needs a source of energy. In this setting, fat is used as the source of energy. Therefore, numbers of cholesterol will go low because it is being used to be converted as energy.

Antioxidant and anti-Inflammatory effects

The fruit contains bioactive phytochemicals (compounds in fruit and vegetables) that act as a strong antioxidant agent. The antioxidant can eliminate reactive oxygen species and other free radicals which induce the inflammation process. Furthermore, the anti-inflammatory effect protects arterial walls’ lining from being damaged. Phytochemicals in star fruit are : 

• Flavonoids
• Proanthocyanidins
• Vitamin C
• β-carotene saponins
• Alkaloids
• Tannins
• Gallic acid

Cardiovascular effects

Apigenin is a type of flavonoid that helps to relax muscles. Blood vessels are composed of smooth muscle cell tissue. When the blood pressure increases, the muscles will become tense. Relaxing the smooth muscle cells helps to lower the blood pressure. Additionally, star fruit is also rich in potassium which is found mostly in hypertensive drugs. Potassium does not affect hypertension directly, but it helps to lower the excretion of sodium which causes hypertension.

Summary

Cardiovascular diseases (CVDs) are a group of heart and blood vessel disorders that can happen to everyone. Even though people in certain groups are prone to develop the disease, behavioural factors play a key role in determining how fast the disease can get to you.

Atherosclerosis is a condition in which fatty plaque forms within the lining of a vessel’s wall. Two medical conditions leading to this condition are hyperlipidemia and diabetes. In addition, hypertension is the leading risk factor for developing cardiovascular disease. Dangerously, both hyperlipidemia and hypertension show no symptoms, hence, they are called “silent killers”.

All of the three underlying medical conditions are caused by your daily habit. An unhealthy diet and sedentary lifestyles as well as tobacco use and harmful consumption of alcohol could accelerate the process of heart problems. Most of the people underestimate these factors, as they are small but mighty. Having a healthy lifestyle is life-changing and prevents us from any health problems and also allows us to have a better quality of life.

The fastest and easiest way to develop a healthy lifestyle starts from eating delicious but nutritious food. Star fruit is a tropical fruit which is flavorful and packed with nutrients. Each star fruit is rich in fibers and antioxidants which help to lower blood glucose and cholesterol, as well as protect the vessels’ walls from damage. Apigenin antioxidants and potassium which are found in star fruit, help to decrease the risk of hypertension.