- Conditions affecting the heart or blood vessels are responsible for a huge number of deaths each year in SA.
- High cholesterol and hypertension are two contributing factors to developing heart disease.
- Here are the dietary and nutritional factors that contribute to good heart health.
Cardiovascular disease is the second leading cause of death in South Africa after HIV/AIDS, according to the South African Heart & Stroke Foundation.
Scientific studies have also shown that heart-related diseases are responsible for more deaths compared to all types of cancers.
High cholesterol and high blood pressure (hypertension) are two major contributing factors to the development of heart disease.
However, in some instances, these factors can be prevented through good nutrition and healthy lifestyle habits. This article explores the dietary and nutritional factors contributing to a state of good heart health in observance of Heart Health this September.
What you need to know about cholesterol and hypertension
Although hypercholesterolaemia (high cholesterol) is a risk factor for heart disease, the right amount of cholesterol plays a vital role in the body. This type of fat forms part of cell membranes and is a precursor for the development of vitamin D in the skin.
Moreover, it is necessary to produce certain hormones such as insulin, growth and sex hormones. Lipoproteins are the vehicles that transport cholesterol through the body. There are mainly two, ranging from low-density lipoprotein (LDL) to high-density lipoproteins (HDL).
The LDL cholesterol is the “bad” cholesterol, which builds up in the arteries and increases blood pressure, while HDL cholesterol helps to remove the bad cholesterol. Consequently, higher ratios of HDL compared to LDL should be present in our bloodstream.
Hypertension is a condition where great force is exerted against the artery walls by circulating blood. This can be caused by consuming foods high in salt, saturated fats, and lifestyle factors, such as physical inactivity and substance abuse.
Eating patterns that help
Dietary Approaches to Stop Hypertension (DASH) are guidelines developed to include nutritious foods to reduce high blood pressure and the risk thereof.
Current evidence in nutrition science shows that eating low-fat and fat-free dairy products overall reduces the risk of mortality related to cardiovascular diseases, and these are included in the DASH dietary pattern.
Additionally, it encourages the consumption of plant-based proteins, grains, fruits and vegetables, which contain various forms of fibre, including soluble fibre, which is known to decrease LDL cholesterol.
Other beneficial foods include lean proteins (fish and legumes), nuts and whole grains, which contain poly- and monounsaturated fats. These help to lower overall blood pressure as well as the level of LDL cholesterol in the blood.
This type of diet is low in ultra-processed foods,
which are high in sodium and saturated fat. These are dangerous, especially for those already suffering from hypertension, as sodium causes water retention, further increasing blood pressure.
Other micronutrients included in the diet, such as vitamins A, E and C (found in many vegetables and fruit), are powerful antioxidants which assist in removing free radicals responsible for oxidative damage and the disruption of the uptake of LDL cholesterol.
Is eating dairy okay?
Research indicates that a high intake of saturated fats and dietary cholesterol contributes to high blood cholesterol levels, including LDL.
Beef, pork chops, chicken skin, full cream dairy products and coconut oil are some of the foods which contain saturated fatty acids.
Several authors of scientific research agree that diets containing low-fat and fat-free dairy products are not associated with an increased risk of strokes or CVDs (cardiovascular diseases). Additionally, decreased blood cholesterol levels and decreased risk of mortality and coronary heart diseases have been observed in people consuming low-fat dairy products compared to full cream dairy products.
READ MORE | Dairy diary: the lowdown and the heads-up
It is important to consider the whole food matrix (the structure of food and nutrients) when it comes to dairy, as there is emerging evidence that points to the cardiometabolic benefits of fermented dairy products even as they contain saturated fats.
In addition to dairy products being sources of high-quality protein and calcium, among other things, fermentation in products such as yoghurts and amasi adds bacteria, which can be beneficial to gut health. This fits into the recommendations stipulated in the South African Dietary Guidelines that encourage the inclusion of a daily serving of amasi or yoghurt.
Eggs and heart health
When it comes to the topic of eggs and cholesterol, a global review of studies indicates moderate egg consumption, defined as up to one egg a day, did not increase the development of heart diseases.
Additionally, there is weak evidence that points to high cholesterol being a result of the consumption of eggs for individuals who do not have high cholesterol. Eggs contain cholesterol; however, there are components within them that interfere with intestinal absorption. This is the opposite for beef and other red meats that contain cholesterol as well as a higher level of saturated fatty acids.
The elusive silver bullet
Unfortunately, including or excluding a single food or food group will not protect you from heart disease. Most studies agree that emphasis should not be placed on individual foods but rather on the entire diet and total fat intake as a determinant for benefits and risks related to heart health.
Keep your diet low in ultra-processed foods and salt by cooking food, being mindful of your dairy and egg consumption, and including a variety of fruits, vegetables, whole grains, plant-based proteins, lean meats, nuts, and seeds all assist in preventing and managing heart disease.
Mékayla Betteridge & Thandeka Sibanda are final year BSc Dietetics students at Stellenbosch University.
This resource is for educational purposes only and cannot replace individual assessment by a healthcare professional. ADSA is the Association for Dietetics in South Africa. Visit www.adsa.org.za to find more dietitians in your area.