SOY PROTEIN EFFECTS ON CARDIOVASCULAR DISEASE

Important note: All information given are just guidelines and prevention options may vary to treatment options. You must consult a medical practitioner before altering, adding to or influencing current treatment or individual practices in any way shape or form.

Cardiovascular disease (CVD) is one of the most expensive health conditions, costing around 5.4 billion dollars of Australia’s total allocated health system expenditure in 2001. The incidence of cardiovascular disease increases with age, and with life expectancy in developing countries rising sharply people are being exposed to these risk factors for much longer periods of time. In 2005, around 3.5 million or 18% of all Australians reported having a form of long-term cardiovascular condition. CVD causes almost 40% of all deaths in most industrialised countries.

An underlying contributor to CVD is atherosclerosis, a process involving abnormal build-up of fat, cholesterol and other substances (plaque) in the inner lining of the arteries. This development of atherosclerosis is slow and complex. Atherosclerotic plaques can often take many years to develop, which is why most clinical studies have focused on more short-term changes in CVD risk factors in association to CVD risks, such as blood cholesterol, blood pressure and vascular function. A large body of evidence has established a role of soy protein in CVD risk reduction.

Soy protein has been consistently found as having beneficial effects in the prevention and management of CVD risk. Studies on healthy, overweight, obese, post/pre menopausal women and the elderly have all suggested that an added intake of soy protein in accordance with a well-structured and balanced healthy diet is highly beneficial in CVD management. Most studies indicate a positive association with respect to the beneficial effect soy has on plasma lipids and in decreasing the risk of CVD. It has been suggested that soy protein has the broadest range of effects on reducing CVD risk and decreasing blood lipoprotein when compared to all of the other cholesterol lowering nutrients.

The primary preventative outcomes of soy are a reduction of total serum cholesterol and low density lipoprotein (LDL) levels and a moderate increase in high density lipoprotein (HDL) levels. Soy protein and soy isoflavones are the two major groups of bioactive components that exert the beneficial effects found from soy products. The two primary isoflavones found in soy are genistein and diadzein. Soy is actually just one of a few foods to contain a source of the phytochemical class known as isoflavones. It has been suggested that soy isoflavones its interaction with other compunds are responsible for the lipid lowering effects of soy. Bodies of evidence supporting this have shown that soy protein containing isoflavones reduce LDL cholesterol levels significantly more than soy protein without isoflavones or isoflavones alone. Soy products have also been identified as having a preventive effect in breast and prostate cancers, however the evidence is limited and further studies need to be undertaken to understand the true effects.

Epidemiological studies have suggested a consumption of soy foods is associated with a reduced risk of CVD. Further studies have concluded that a substitution of soy protein for animal products can lower total blood cholesterol and LDL cholesterol significantly. A composite meta-analysis of 38 clinical trials found that an average consumption of 25-40g per day of soy protein led to a 9% decline in total cholesterol and a 13% decline in LDL cholesterol. Soy products potentially have multifaceted health-promoting effects, including cholesterol reduction, improved vascular health, preserved bone mineral density, and a reduction of menopausal symptoms. Compared with diets absent from soy products, soy diets resulted in significantly lower total cholesterol and ratios of total LDL to HDL cholesterol.

Established lipid-lowering drugs, although effective, are often accompanied by adverse reactions. A far more recommended intervention which should always be recommended and attempted first is that of dietary methods, by way of a restricted saturated fat and sodium consumption and increased intake of dietary fibres, fruits, vegetables, potassium, legumes and soy products. Supplementation of 25-40 grams of soy protein, consumed preferably through an individuals diet daily, results in a significant decrease in LDL cholesterol levels and increase in HDL cholesterol. Its use is likely to diminish the risk of coronary heart disease. Dietary interventions should last for around at least 6-12 weeks for any significant results to emerge.

TAKE HOME MESSAGE: Soy protein, in combination with a well balanced diet, plays a pivotal role in CVD prevention. Increased intakes of fiber, vegetable oils, proteins from soy and legume products, nuts, fruits and vegetables and respecting a low sodium, high potassium diet has the most beneficial effects than any one factor alone. 30 – 60 minutes of moderate intensity physical activity daily is also recommended in association with a well balanced diet for the best results. Above all results are seen in the long-term effects to those who adhere to changes as life long practices.

Filed under: Useful Informations

Like this post? Subscribe to my RSS feed and get loads more!