Coronary Heart Disease (Leaving Cert Home Economics): Revision Notes
Coronary Heart Disease
What is coronary heart disease?
Coronary Heart Disease (CHD) is a serious condition where blood flow to the heart muscle becomes restricted. This happens because fatty deposits called plaque build up inside the coronary arteries (the blood vessels that supply the heart). The plaque contains cholesterol, fats, calcium and other substances that gradually narrow the arteries.
CHD can cause chest pain (angina) and heart attacks. It's one of the leading causes of death globally, making it essential to understand how diet affects this condition.
Understanding cholesterol transport
The body uses special carriers called lipoproteins to move cholesterol through the bloodstream. These play a crucial role in CHD development:
High-density lipoproteins (HDL)
Often called "good cholesterol", HDL particles work like cleanup crews. They collect cholesterol from artery walls and transport it back to the liver where it can be processed and removed from the body. Higher HDL levels protect against CHD.
Low-density lipoproteins (LDL)
Known as "bad cholesterol", LDL particles can deposit cholesterol directly onto artery walls. This creates the fatty plaques that cause atherosclerosis (artery hardening). When LDL levels are too high, CHD risk increases significantly.
The balance between HDL and LDL cholesterol levels is crucial for heart health. Think of HDL as the body's natural cleaning system, while LDL can be problematic when levels become too high.
Dietary factors that increase CHD risk
Several dietary components can worsen CHD by raising harmful cholesterol levels or creating other cardiovascular problems:
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Saturated and trans fats - Found mainly in red meat, full-fat dairy products and processed foods, these fats directly increase LDL cholesterol levels in the blood
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Dietary cholesterol - Present in animal-based foods, excessive intake can further elevate blood cholesterol levels
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Salt (sodium chloride) - High salt consumption leads to hypertension (high blood pressure), which puts extra strain on the heart and arteries
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Sugar - Particularly refined sugar, excessive consumption contributes to obesity and type 2 diabetes, both major risk factors for developing CHD
Nutritional deficiencies linked to CHD
Certain nutrients help protect against CHD, so inadequate intake can increase risk:
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Fibre - Found in fruits, vegetables and whole grains, fibre helps remove cholesterol from the body. Low fibre intake allows cholesterol levels to rise
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Omega-3 fatty acids - These healthy fats from oily fish like salmon have protective effects against CHD, but Western diets often lack sufficient amounts
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Antioxidants and vitamins - Colourful fruits and vegetables provide compounds that protect arteries from damage. Diets lacking these foods may contribute to CHD development
The nutrients listed above work as natural protectors for your cardiovascular system. A diet rich in these compounds can significantly reduce CHD risk when combined with other healthy lifestyle choices.
Dietary management of CHD
People with CHD need specific dietary changes to manage their condition effectively:
Reduce harmful components
- Replace saturated fats with monounsaturated and polyunsaturated fats (found in olive oil, avocados, nuts and seeds)
- Limit processed and high-sodium foods to control salt intake
- Moderate alcohol consumption, as excess alcohol raises blood pressure and triglyceride levels
Increase protective foods
- Eat more fruits, vegetables and whole grains to boost fibre consumption
- Include sources of omega-3 fatty acids like oily fish
- Choose lean proteins to reduce saturated fat intake
Overall dietary approach
A Mediterranean-style diet works particularly well for CHD management. This eating pattern emphasises fruits, vegetables, whole grains, lean proteins and healthy fats whilst limiting processed foods.
Practical Example: Mediterranean-Style Meal Planning
Breakfast: Oatmeal topped with berries and chopped walnuts Lunch: Grilled salmon with quinoa and roasted vegetables drizzled with olive oil Dinner: Lentil and vegetable soup with whole grain bread Snacks: Fresh fruit, small handful of nuts, or vegetable sticks with hummus
This approach provides plenty of fibre, omega-3 fatty acids, and antioxidants while keeping saturated fat and processed foods to a minimum.
Additional lifestyle considerations
Diet alone isn't enough - other factors also influence CHD risk:
- Physical activity - Regular exercise complements dietary changes by improving cardiovascular health
- Stress management - Chronic stress contributes to heart disease, so learning stress reduction techniques helps
- Regular monitoring - Health check-ups allow early detection and management of cholesterol levels, blood pressure and blood sugar
Key Points to Remember:
- CHD occurs when plaque blocks coronary arteries, reducing blood flow to the heart muscle
- HDL cholesterol is protective whilst LDL cholesterol contributes to dangerous plaque formation
- Limiting saturated fats, salt and sugar whilst increasing fibre and omega-3s helps prevent and manage CHD
- A Mediterranean-style diet provides the best overall approach for heart health
- Combining good nutrition with regular exercise and stress management gives the best protection against CHD