Heart Health and Blood Pressure

Blood makes up approximately 7% of a human’s total body weight and is the primary transport system in the body [1]. The main “steam engine” of the blood system is the heart. Disruption of the blood, vasculature or heart can create detrimental problems to the health of the whole body.

What is the cardiovascular system made up of?

The cardiovascular system is made up of 4 components, the heart, arteries, veins and capillaries. All 3 components of vasculature differ in structure. The artery is a vessel used to carry blood away from the heart and to active tissues. The blood is pumped from the heart at very high pressures into the artery which must withstand and maintain these high pressures. The lumen (diameter) of the artery is very narrow, which maintains the blood at high pressures until it reaches the tissues. The arterial wall is made of elastic fibres to stretch to withstand the high pressures.

The valved veins transport deoxygenated blood from the tissues back to the heart. The blood in this system travels at lower pressures due to the larger lumen. Blood is only returned as muscles contract, they squeeze the flexible collagen in the vein forcing the blood back to the heart.

Lastly, the capillaries are vessels that pass through the narrow gaps of the tissues and organs. They are frequently described as “exchange points” for gas, nutrients and waste between the blood and tissues. The walls and lumen are very thin to allow for efficient exchange. [2]

What causes damage and disease to these systems?

There are a few well-known diseases and disorders associated with ill health of the cardiovascular system, namely hypertension, atherosclerosis and myocardial infarctions.

Hypertension

Hypertension is the clinical name for high blood pressure. A normal measurement is 120/80mmHg (systolic/diastolic).

• Stage 1 hypertension is classified as 140/90mmHg

• Stage 2, 160/100mmHg [3].

High blood pressure can be caused by unmodifiable factors such as age, gender, ethnicity and congenital problems. On the other hand, it can be caused by lifestyle and nutrition, e.g. high salt/sodium diet, lack of fruit and vegetables, lack of exercise, or smoking, and a high fat and cholesterol diet. Hypertension causes structural damage, such as atherosclerosis and has the capability to burst capillaries by exerting high pressure on the delicate structures.[4]

Atherosclerosis

Atherosclerosis is the hardening of the arteries. Stemming from the Greek, “Athero” meaning “gruel” or “wax” and “Sclerosis” meaning “to harden”. The pathology is formed from fatty plaques deposits in the inner linings of the arteries. They then rupture causing a further narrowing of the artery. The progression of the disease is advanced if there is damage caused to the arterial lining by hypertension or smoking. Narrowing of the artery can cause further hypertension, Thrombosis (ectopic clotting), Ischemia (reduced blood supply), or myocardial infarctions (heart attacks). [5]

Myocardial Infarctions

This is the medical term for a heart attack, this is caused by lack of blood supply thus, lack oxygen to the heart. This causes the heart tissue to die. The most common cause (95% of the cases) is Atherosclerosis. There are unfortunate genetic predispositions that cause this, but lifestyle factors such as poor diet, obesity, lack of exercise, and smoking are also risk factors. [6]

How can I prevent this?

Dietary changes could include following the DASH (Dietary Approaches to Stop Hypertension) or Mediterranean diet. Reducing cholesterol, fat and salt in the diet. Increasing fruit and vegetable intake, to more than 5-a-day. Moreover, if you are a smoker you should consider quitting smoking and taking up more cardiovascular exercise. In addition, you should consider incorporating the following into your diet:

Nitrates

Nitrates can be found in spinach, celery, lettuce and beetroots [7]. They are chemical components that generate Nitric Oxide (NO). These have potent hypotensive, cell-protective and anti-coagulative properties in the blood [8]. Which means a reduction in blood pressure and risk of atherosclerosis. A 2015 study found that daily nitrate consumption was associated with decreased blood pressure recordings and enhanced vascular function. [9]

Omega 3 Fish oils

A study conducted on the diet of native Inuits revealed their Omega 3 rich diet contributed to their implausibly low rates of cardiovascular disease [10]. Omega 3 is rich in EPA and DHA[11], which have anti-coagulation and anti-inflammatory properties. A study of 3500 patients showed 1 gram/day Omega 3 can reduce the risk of cardiovascular disease. [12]

Oat Beta-Glucans

Beta-glucans are polysaccharides (a type of carbohydrates) typically found in foods such as oats, which have been shown to reduce cholesterol, a primary risk for cardiovascular disease (CVD). [13]

Vitamin C

Although, this requires more research Vitamin C has been shown to decrease the risk of coronary heart disease (CHD) by as much as 11% when increasing intake by as little as 0.5mg. Those participants that exceeded this intake showed a risk decrease as great as 27%. [14]

Supplements. Both Omega 3 fish oils and Vitamin C can be taken in supplement form. Other supplements to be considered include Beetroot Extract, Dong Quai, and Plant Sterols.

Beetroot extract is rich in nitrates clinically proven to reduce hypertension. One study on beetroot showed a decrease in blood pressure in as little as six hours after consuming the extract [15]. Secondly, Dong Quai is a botanical extract from the plant Angelica Sinensis. Its nicknamed the“Blood mover”, which comes from its use in Chinese medicine. It is thought to “invigorate” the blood [16]. Lastly, are the plant sterols, or stanol esters. They are active competitors for dietary cholesterol so that it is not absorbed, reducing the risk of cardiovascular disease [11].

Look after your heart and it will look after you.