This is an edited extract from her presentation:

The proportion of people with heart, stroke and vascular diseases is increasing; 19.4% of the total Australian population is living with a medically diagnosed cardiovascular disease.

The leading risk factors for cardiovascular disease are:

• 12.2% - tobacco use 
• 10.9% - high blood pressure 
• 9.2% - alcohol 
• 7.6% - high cholesterol 
• 7.4% - obesity 
• 3.9% - low fruit and vegetable intake

Facts about Diabetes

275 Australians are diagnosed with diabetes every day and the estimate of the number of adults living with diabetes has tripled since 1981. By 2030, more than 1.6 million Australians will have diabetes.

More than 2.5 million Australians have Metabolic Syndrome. People with Metabolic Syndrome are three times as likely to have a heart attack or stroke than people without the syndrome, and twice as likely to die from a heart attack or stroke.

The prevalence of obesity in Australia has increased over the past 20 years and is continuing to rise.

Epidemiological studies (left) show nut consumption reduces the risk of cardiovascular disease (CVD) eg. The Adventist Health Study, Iowa Women's Health Study, Nurses' Health Study, CARE Study.

Nut consumption reduces CVD risk by between 18-57%.

All the studies show the same thing, that eating some nuts decreases the risk of CVD, even in the oldest of the old.

The Physicians Health Study also showed that nut consumption also decreases the risk of sudden cardiac death. 

Two servings of nuts a week decreased the risk by 50%; one serving decreased the risk by 40%.

Researcher Frank B. Hu found that consumption of peanuts two to four times a week decreased CHD risk by 40%. Rui Jiang reported in 2002 that consumption of peanut butter more than five times a week decreased the risk of developing Type 2 Diabetes by 21%.

Peanuts have a low glycemic load, ie. blood glucose levels rise more slowly and insulin demand is lower than after a high-glycemic load meal. High dietary glycemic loads have been associated with an increased risk of developing Type 2 diabetes.

Research carried out in Australia by C.S. Johnston has shown that peanut products and vinegar attenuate post-prandial glycemia, ie after a meal blood glucose levels can rise quickly and drop away rapidly, however adding peanut products to the meal lowers the initial rise and keeps glucose levels at a stable level for almost twice as long.

Peanuts also have a lipid-lowering effect. Research has shown that a peanut diet lowers total cholesterol and LDL-cholesterol. A randomised controlled trial of nine men and 13 women with normal cholesterol levels carried out by Penny Kris-Etherton in 1999 showed a 10.9% decrease in total cholesterol levels, a 13.9% decrease in LDL cholesterol and only a 2.3% drop in HDL ("good") cholesterol.

Other research has shown that the observed changes in CHD risk attributable to the changes in fatty acid profile after eating nuts were greater than predicted, especially when they were consumed two to four times a week. Total and LDL cholesterol levels were also lower than predicted. So there must be something else in nuts other than the monounsaturated fat that is creating these benefits.

Clinical Studies with Peanuts and Peanut Products Conducted in the Metabolic Diet Study Centre, Penn State University

Pennsylvania State University's Metabolic Diet Study Centre (right) carried out controlled feeding and controlled weight loss studies comparing moderate fat versus low fat diets.

Peanuts and peanut products were the major source of unsaturated fat in the diets. 

They also compared the effects of a high monounsaturated fat (MUFA) diets versus a low-fat diet on lipids and lipoproteins.

Counterintuitively, the low-fat diet increased triglycerides in the blood. In comparison, the moderate-fat diet decreased triglycerides.

The high MUFA diet also favourably affected cardiovascular disease risk. The moderate fat (from peanuts) weight loss diet also reduced CVD risk.

Low-fat, high carbohydrate diets actually increased triglycerides while decreasing HDL cholesterol. However, after weight loss, triglycerides decrease and HDL cholesterol increases. 

Conclusion: A moderate “good-fat” diet, high in peanuts and peanut products (replacing 50% of fat in diet with peanuts, peanut butter and peanut oil) yields beneficial changes in lipid profile versus a low-fat diet. 

A weight-loss diet, rich in monounsaturated fat leads to a greater reduction in CVD risk than a low-fat, high-carbohydrate diet. 

Epidemiologic studies report a negative association between nut consumption and dody mass index. Nut feeding studies report short-term consumption of a moderate to large amount of nuts does not increase body weight.

Peanuts contain:

• Vitamins - Vitamin E, Folate, Thiamine, Riboflavin, Niacin, Vitamin B6

 
• Magnesium - A mineral nutrient missing in many Western diets. Young adults with higher magnesium intake also have a lower risk of developing Metabolic Syndrome. Blood pressure levels are also inversely linked to blood magnesium levels and magnesium deficit may be an underlying mechanism leading to insulin resistance

 
• Other Minerals - Copper, Potassium, Selenium, Calcium, Phosphorous, Iron, Zinc, Manganese

 
• Fibre - 8.5g/100g. Dietary fibre intake has been linked to CVD risk

 
• Phytochemicals - Controlled clinical feeding studies have shown that consumption of phytostanols and phytosterols lowers total cholesterol levels and LDL cholesterol levels with no effect on HDL cholesterol

 
• Reseveratrol - A phytosterol that inhibits lipid and LDL cholesterol oxidation, increases free radical scavenging activity, inhibits platelet aggregation and has anti-inflammatory characteristics

 
• Plant protein (arginine) - The body uses arginine to create nitric oxide, a vasodilator which promotes the growth of new blood vessels, stimulates muscle cell relaxation and inhibits platelet aggregation

 
• Unsaturated fat

Interview with Prof Kris-Etherton

Presentations by other speakers

Prof Kris-Etherton's biography

Research by Prof Kris-Etherton