March 2006 Newsletter

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

Welcome to the March edition of the HEC newsletter This edition looks at scientific studies published on: soy versus dairy meal replacements, caffeine in soft drinks and blood pressue, magnesium and bone mineral density, fish oil and abdominal obesity, lipoic acid, noni juice 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 $135 hardcopy and online or $120 on-line only

APJCN vol 15, issue 1, 2006 issue out now - read abstracts.

Find out the latest in nutrition research in issue 1 : what is the the emerging 'new' nutrition science; health and nutrient claims on Australian food products and compliance with regulations; is grain fed meat higher in omega 3 fats than grass fed meat; can iron deficiency affect your thyroid function and much more read abstracts.

WHAT'S NEW IN NUTRITION RESEARCH

Soy versus milk based "meal replacements" for weight loss

In a recent study, of overweight men and women, researchers compared the weight loss and blood lipid effects between reduced-calorie milk- and soy-based beverage meal replacements. After 12 weeks on a 1,200-calorie per day diet which included 2 to 4 soy- or milk-based meal replacements, men and women in both groups lost about
8-9 % of their initial body weight. However, people who consumed the soy-based meal replacements experienced
more...

Caffeine containing soft drinks (but not coffee) found to raise blood pressure

Most people can safely consume up to 250 milligrams of caffeine (equivalent to about 3-4 cups of coffee) per day. Caffeine can cause small spikes in blood pressure in sensitive individuals, which could be dangerous for people with high blood pressure or heart disease. However, in a study of hypertension-free women, drinking 2-3 glasses of caffeine-containing colas (regular and 'diet') daily was associated with an increase in blood pressure and more....


Magnesium important for strong bones but watch out for zinc supplements

Low bone mineral density is common in the community, with 50% of women aged 80 and over presenting with osteoporosis.

Most people know they need calcium and vitamin D to build strong bones, but new research reveals that omega 3 fats and magnesium are also important for maintaining bone mineral density to prevent the development of osteoporosis. Magnesium is also essential in many enzyme systems, is essential for muscle contraction and nerve function and helps in glucose metabolism and the release of energy (making it a particularly important mineral in diabetes as well).

A number of studies suggest that sub-optimal intake of magnesium is common and that subgroups such as people with diabetes and hypertension are commonly magnesium deficient. Magnesium deficiency is known to result in a decreased synthesis, release and action of the bone hormone 'parathyroid hormone' and 1,25 vitamin D.

In a study of 2038 adults aged 70 and over, subjects who consumed the highest amount of magnesium (from their diet and/or supplements) experienced higher bone mineral densities compared to the people whose diets contained the least amount of magnesium. The association of high magnesium intake and bone density was statistically proven after controlling for factors which also influence bone density like calcium, vitamin D, body weight, smoking, alcohol, execrise, use of diureticis or use of oestrogen medication. more

._______________________________________________________________________________________________________________

Fish oil (high DHA type) combined with exercise can reduce abdominal fatness

A study by Alison Hill, PhD student from the University of South Australia (abstract published in Asia pacific Journal of Clinical Nutrition) showed that 6g (or 6x1g capsules) of fish oil (high DHA content) daily for 3 months reduced body fat by 5% especially from the abdominal (visceral) region, only when combined with moderate aerobic exercise for 45 minutes 3 times a week. The groups that were placed on fish oil alone or exercise alone did not lose abdominal fat. It is known that omega-3 fatty acids from fish oil increase the expression of fat burning enzymes, but until now the implications of this in humans was not entirely clear. This study suggests that although fish oil increases the expression of fat burning enzymes taking it alone will not have a significant effect but that it needs a driver - exercise - to increase metabolic rate and lower body fat. more

NUTRITION RESOURCES ON THE WEB

Lipioc acid - a sulphur contianing antioxidant fatty acid which is both water and fat soluble made by the body but also found in liver and yeast. Preliminary and sometimes contradictory evidence suggests that lipoic acid may improve diabetic neuropathy and other aspects of diabetes, including blood sugar control and the development of long-term complications such as diseases of the heart, kidneys, and small blood vessels more

Noni juice (or powder) - has been heavily promoted for an enormous range of uses but there is no real evidence that it is effective for any of these conditions. At best it may be useful in treating constipation. more

______________________________________________________________________________________________