A diet high in Omega-3 fatty acids and low in salt can help decrease the odds of falling victim to Australia’s biggest killer.
The Australian Institute of Health and Welfare names cardiovascular disease as the leading cause of death and disease burden in Australia, representing 30 per cent of all deaths. CVD risk is compounded by other chronic diseases that share the same modifiable risk factors. Nutrition and other lifestyle factors play an important role in prevention and management of CVD.
Chronic diseases such as diabetes and chronic kidney disease are among those that share a number of risk factors with CVD.
Although these complex interactions are not well understood, diabetes has been shown to greatly increase the risk of CVD. Diabetes doubles the risk of CVD, with prevalence rates of heart attacks up to 10 times greater and prevalence rates of stroke up to five times greater. Metabolic syndrome (MetS, also known as Syndrome X) – comprising insulin resistance, abdominal fat accumulation, dyslipidemia, and hypertension – further exacerbates the risk of CVD and total mortality.
Individuals with just one or two MetS risk factors carry double the risk of mortality from CVD, suggesting that risk is not ‘optimal’ unless all risk factors are absent.
A 2003 study published in the New England Journal of Medicine has indicated that intensive treatment for people with diabetes involving control of blood pressure, blood sugar and blood lipids can result in a 50 per cent reduction in macrovascular and microvascular complications.
The American Journal of Cardiology further supports that a huge 80 per cent of coronary heart disease events in individuals with MetS may be preventable through optimal control of LDL-c, HDL-c and blood pressure.
The main indicators of increased CVD risk are high blood cholesterol and triglycerides, hypertension, and being overweight or obese.
Hypertension itself (starting at systolic 115mmHg) is the most significant cause of CVD, accounting for 62 per cent of strokes and 49 per cent of coronary heart disease (CHD). Much of Australia’s chronic disease burden is preventable and could be significantly reduced by addressing modifiable behavioural risk factors. These include insufficient physical activity, poor diet, excessive alcohol consumption and tobacco smoking.
Australians’ high consumption of salt is a major factor in increased blood pressure and, therefore, CVD. However, risks that are independent of elevated blood pressure (but additive), including stroke, left-ventricular hypertrophy and renal disease, are also apparent. The diversity and strength of the evidence connecting blood pressure and salt is stronger than for other lifestyle factors, such as being overweight, inadequate fruit and vegetable consumption, and little or no exercise.
In addition, over the past four decades, numerous scientific reports have examined the relationships between physical activity, fitness and cardiovascular health. More active and fit individuals developed less heart disease than their sedentary counterparts.
The most favourable effects of exercise on the risk factors for CVD are weight loss, reductions in blood pressure, improved blood lipid profile and better insulin sensitivity in people with diabetes. Dramatic improvements are particularly noted when smoking cessation, medicine and proper nutrition are also included.
Omega-3 fatty acids obtained from certain seafood, nuts and plant oils are reported to improve CVD, reducing CV events such as non-fatal heart attacks and strokes, death and atherosclerosis.
The Heart Foundation recommends 250–500mg of marine sourced omega-3s (EPA, DHA) and 1g of plant sourced omega-3s (ALA) each day.
The scientific evidence supports oily fish such as salmon, sardines and mackerel as the best dietary source of omega-3s. Higher fish intakes are consistently associated with lower rates of heart disease (heart failure and sudden cardiac death), myocardial infarctions and stroke.
Sources of ALA include walnuts, linseed/flaxseed, canola and soybean oil and chia seeds. A diet with Omega-3s, vegetables, fruit, legumes, wholegrain breads and cereals, lean meats and alternatives, fish, nuts and seeds, reduced fat dairy, healthy fats and oils, plus limited salt and saturated fats is crucial for better heart health.
It is important to shine light on the fact that CVD risk may also stem from childhood. Multiple epidemiological studies have demonstrated a disturbing increase in the prevalence of obesity beginning in childhood, with 25 per cent of Australian children classified as overweight or obese.
This is in addition to the 63 per cent of Australian adults who are overweight or obese. Given the strong association between obesity and hypertension, dyslipidemia, and type II diabetes mellitus beginning in childhood, this is cause for concern. Long-term follow-up studies have indicated the development of obesity, hypercholesterolemia, and hypertension from childhood into adult life, increasing CVD risk.
There is mounting evidence in literature that lifestyle modifications can reduce the risk of chronic disease. Improved nutrition has a powerful influence on a host of chronic diseases, including CVD.
Katherine Baqleh is an accredited practising dietitian and nutritionist and founder of Health Victory Nutrition Experts, a private practice and nutrition consultancy. Follow Katherine on Twitter.Do you have an idea for a story?
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