What is the Cardiovascular System?

The cardiovascular system (CVS) is a network of chambers and vessels that transfers blood to and from every tissue in the body. The heart is an essential part of the cardiovascular system, made up of cardiac muscle, lining four distinct chambers.   When the lower right chamber (right ventricle) of the heart muscle contracts, this provides a pump like action, sending oxygen and nutrient rich blood to our tissues via the arteries. At the tissues, our cells use oxygen in a biochemical reaction to make cellular energy known as ATP.  The deoxygenated blood and by-products of cellular respiration (including carbon dioxide) then return to the heart through the veins. This blood gets pumped by the lower left chamber to the lungs, where re-oxygenation and gas exchange happens.   Since optimal function of the cardiovascular system is associated with flow of blood through the body and the health and function of all tissues, making adjustments to modifiable risk factors for cardiovascular disease,  should be at the forefront of preventative medicine.

What causes damage to Cardiovascular system?  

Cardiovascular disease (CVD) is a leading cause of mortality and morbidity in the western world, with 1 in 3 deaths in NZ attributed to this cause. Atherosclerosis is one of the main manifestations of damage to the cardiovascular system, involving the gradual narrowing and hardening of arteries, due to accumulation of plaque, containing cholesterol, calcium and macrophages (white blood cells). Complete blockage of the arteries or rupture of atherosclerotic plaques is what typically causes life-threatening myocardial infarction (heart attack) and stroke.

Although genes have a part to play in the onset of CVD, there are a range of modifiable risk factors in the development of atherosclerosis and other conditions of the CVS including dyslipidaemia (dysregulated blood cholesterol), hypertension (high blood pressure), elevated body mass index, unstable blood glucose levels, oxidative stress and inflammation. Dietary and lifestyle factors that exacerbate the risk factors for CVD include:

• Inflammatory foods such as trans fats (margarine, vegetable shortening) and industrialised seed oils (sunflower, canola, and soy bean)

• Processed and packaged foods containing refined carbohydrates and sugar that contribute to poor blood glucose regulation and insulin resistance

• A diet lacking in fresh colourful antioxidant rich fruit and vegetables that are protective against oxidative damage

• Lack of physical activity and sedentary lifestyle

• Exposure to environmental toxins including tobacco smoke

• Mental, emotional and physical stress


How to support cardiovascular health through diet:  

Dietary shifts towards a wholefoods-based anti-inflammatory diet, like the Mediterranean diet, are supportive of cardiovascular health, lowering blood pressure and normalising blood cholesterol levels.

• Make half your plate look like a rainbow with colourful antioxidant rich vegetables and a few portions of fruit per day

• Eliminate trans-fats and industrialised vegetable seed oils

• Increase the intake of omega-3 fatty acids by including fatty fish such as salmon and sardines, pasture raised eggs, walnuts and flaxseed • Include plenty of extra virgin olive oil, nuts, seeds and fermented dairy

• Ensure you have optimal levels of B12, folate and other methylation supportive nutrients to help normalise homocysteine levels, by adding organic chicken or beef livers, other organ meats, seafood, dark green leafy vegetables, cruciferous vegetable like broccoli and cabbage and egg yolks

• Eliminate refined sugar and swap out refined carbohydrates like white bread, pasta, white rice for fibre-rich complex carbohydrates such as quinoa, buckwheat, whole oats, kumara and pumpkin.

What lifestyle factors to adopt  

Physical activity helps with weight management, improves insulin sensitivity, reduces inflammation and supports healthy blood pressure levels and blood lipid profile. Including an average of at least 150 minutes per week of graded physical activity, where aerobic activity is slowly increased to match a person’s fitness level, is associated with a reduction in CVD risk. This could be done by including walking, swimming and a strengthening yoga practice.   Stress is a leading risk factor for hypertension, dyslipidaemia, dysregulated blood sugar levels and inflammation, through the actions of the stress hormone cortisol. It is therefore important to adopy regular stress management techniques and rituals such as meditation and mindfulness, yoga, deep diaphragmatic breathing, journaling and time in nature.

Sauna bathing and cardiovascular health  

Regular heat therapy through sauna bathing and hot water immersion may lead to improvements in cardiovascular function through positive effects on the health of our vasculature. A prospective 30-year study identified that people that were lifelong sauna bathers had lower cardiovascular-related deaths.    The cardiovascular protective effects of heat therapy include an improvement in endothelium-dependent dilatation, reduced arterial stiffness, modulation of the autonomic nervous system, beneficial changes in circulating lipid profiles and lowering of systemic blood pressure! With regular sauna bathing, there is the added benefit of sweating, which aids the elimination of toxins that contribute to oxidative damage and inflammation. Despite these outlined benefits of heat therapy for cardiovascular function, in the presence of any pre-existing conditions it is recommended that consultation with a healthcare provider takes place.


Written by Shaz Andrew, Naturopath & Holistic Nutritionist