April 2006 Newsletter

Prof Mark Wahlqvist AO, MD, FRACP Immediate Past President International Union of Nutritional Science

Welcome to the April edition of the HEC newsletter This edition looks at scientific studies published on: homocysteine and heart disease, magnesium and metabolic syndrome, stepping/stair climbing andheart health, ageactive execise video is now on-line (free), Professor Mark Wahlqvist's resume and list of publications also: read abstracts of the new edition vol15 (1) of the Asia Pacific Journal of Clinical Nutrition

Dr Antigone Kouris-Blazos PhD, Grad Dip Diet, BSc (Hons) Honorary Nutrition Research Fellow, Monash University

Asia Pacific Journal of Clinical Nutrition Subscribe to APJCN for only $195 hardcopy and online or $150 on-line only

Free access to Prof. Wahlqvist's published papers

WHAT'S NEW IN NUTRITION RESEARCH

Elevated levels of the amino acid 'homocysteine' not proven to cause heart attacks or stroke

Homocysteine is an amino acid ( a building block of protein) formed from another amino acid called methione which we consume from food. Homocysteine is toxic to blood vessels (damages the cells lining the inside of the arteries, and interferes with clotting factors) so the body converts it to the amino acids taurine and cysteine withe the help of 3 vitamins - folate, vitamin B6 and vitamin B12. If the diet lacks these vitamins then homocysteine levels rise potentially increasing the risk of blood clots, heart attack and stroke. To date most studies have reported an "association" between elevated blood homocysteine and heart disease - which does not prove cause and effect.
Since homocysteine is lowered by B vitamins, especially folic acid, trials of folic acid, B12 and B6 were commenced to prevent heart attacks and strokes. Studies reported in 2006 (one study included 9000 people) have shown that giving these vitamins to reduce homocysteine levels does not give any benefit and suggested that if given with B12 might instead increase some cardiovascular risks. These studies suggest that homocysteine may not be a risk factor at all or it may simply be a 'marker' for something else. more..

http://en.wikipedia.org/wiki/Homocysteine
http://www.abc.net.au/health/minutes/stories/s1596271.htm
http://www.quackwatch.org/03HealthPromotion/homocysteine.html

Magnesium important for preventing the "metabolic syndrome or syndrome x"

Metabolic syndrome is a condition that dramatically increases the risk of developing heart disease, diabetes, fatty liver and has even been linked to depression. One is considered to have metabolic syndrome if they have 3 or more of the five criteria:
1. abdominal obesity (waist circumference >102cm in men and >88cm in women),
2. high blood triglycerides (>1.69mmol/l)
3. low HDL cholesterol (<1.04 mmol/l in men and <1.29mmol/l in women)
4. hypertention (>130/85 mmHg)
5. insulin resistance (fasting glucose >5.5mmol/l and triglycerides/HDL cholesterol >1.8mmol - this ratio is a surrogate measure for dangerously elevated blood insulin levels.

Disturbingly, the prevalence of metabolic syndrome is soaring, paralleling that of other chronic disease epidemics. Currently over 5 million people in Australia have metabolic syndrome and an increasing number of adolescents are presenting with the condition. The causes of metabolic syndrome include: family genetics, stress, sedentary lifestyle, high refined carbohydrate diet/high glycaemic load diet, nutrient poor diet (especially low magneium diet), high calorie/fat diet, inflammatory disorders, hormone imbalance more....

Magnesium intake and incidence of metabolic syndrome among young adults. He, K., Liu, K., Daviglus, M. L., Morris, S. J., Loria, C. M., Van Horn, L., Jacobs, D. R. Jr., Savage, P. J., Circulation 2006 Mar 27; 113:1675.

____________________________________________________________________________________________________________

Accumulating short bouts of "stepping" activity throughout the day can favourably alter important cardiovascular risk factors

Fifteen women aged 18-20 years were randomly assigned to control (n = 7) or stair climbing (n = 8) groups. Stair climbing was progressively increased from 180 steps (2 min) a day in week 1 to 900 steps (10 min) a day in weeks 7 and 8. Training took place five days a week on a public access staircase at a stepping rate of 90 steps a minute. Subjects agreed not to change their diet or lifestyle over the experimental period. Relative to controls, the stair climbing group displayed a 17.1% increase in fitness (VO2MAX) and a 7.7% reduction in low density lipoprotein cholesterol (p<0.05) over the training period. No change occurred in total cholesterol, high density lipoprotein cholesterol, triglycerides, or homocysteine. The study confirms that accumulating short bouts of stair climbing activity throughout the day can favourably alter important cardiovascular risk factors in previously sedentary young women. They also concluded that 10min of stepping was equivalent to a 30min walk with respect to cardiofitness and that stepping/stair climbing may be easily incorporated into the working day and therefore should be promoted by public health guidelines.

Boreham CAG, Kennedy RA, Murphy MH, Tully M, Wallace WFM, Young I. Training effects of short bouts of stair climbing on cardiorespiratory fitness, blood lipids, and homocysteine in sedentary young women. British Journal of Sports Medicine 2005;39:590-593
http://bjsm.bmjjournals.com/cgi/content/abstract/39/9/590

EXERCISE PRODUCTS ON THE WEB

"Ageactive" video on-line - free video snippets of exercises designed to keep you toned, flexible and strong - brought to you by physiotherapist Marketa Van Valen and HEC's Professor Mark Wahlqvist

"Step-fit" wooden step - step into cardiofitness, metabolic fitness and weight management with Step-fit for only $65 (inc postage anywhere in Australia). As little as 2-10minutes of stair climbing daily has been shown to improve cardiofitness (Boreham et al., BJ Sports Med, 2005; 39: 590-593). Step-fit is a convenient surrogate for people who do not have access to a staircase or who have difficulty climbing stairs. Step-fit is designed by engineers, in consultation with a clinical nutritionist and physiotherapist, for safe stepping exercises and to withstand body weights of over 300kg. Position near your desk or TV for convenient indoor access to exercise.Step-fit is delivered to you flat packed and can be self assembled in minutes without nails or screws and has a soft rubber top to soften the stepping impact. Plastic gym steps (stepreebok) cost $100 or more.....

______________________________________________________________________________________________