News Briefs

Senior moments? It may be your blood glucose.
Senior moments are a normal, albeit unwelcome, part of aging, rather like wrinkling skin and graying hair. Scientists call them ‘cognitive aging,’ the result of changes in brain chemistry and physiology that affect our brain’s ability to think. Researchers at Columbia University Medical Center in New York suggest in Annals of Neurology, that controlling blood glucose may be a key factor in slowing down the normal changes as we age and preserving our cognitive health.

None of the 240 participants (average age 80) in the Columbia University study had symptoms of dementia or Alzheimer’s. Mapping their brain regions using high-resolution functional magnetic resonance imaging, the researchers found a correlation between elevated blood glucose levels and reduced cerebral blood volume, or blood flow, in the dentate gyrus, an indication of reduced metabolic activity and function in that region of the brain.

‘Our findings suggest that maintaining blood glucose levels, even in the absence of diabetes, could help maintain aspects of cognitive health. More specifically, our findings predict that any intervention that causes a decrease in blood glucose should increase dentate gyrus function and would therefore be cognitively beneficial,’ said Dr. Small. ‘Whether with physical exercise, diet or through the development of potential pharmacological interventions, our research suggests that improving glucose metabolism could be a clinically viable approach for improving the cognitive slide that occurs in many of us as we age,’ concluded Dr. Small.

Scott Small MD

Fruit and vegetables may strengthen your bones
Diets that are high in protein and cereal grains produce an excess of acid in the body which may increase calcium excretion and weaken bones, according to a new study published in the Journal of Clinical Endocrinology & Metabolism. The study found that increasing the alkali content of the diet, with a pill or through a diet rich in fruits and vegetables has the opposite effect and strengthens bone health.

‘Heredity, diet, and other lifestyle factors contribute to the problem of bone loss and fractures,’ said lead author Dr Bess Dawson-Hughes of Tufts University. ‘When it comes to dietary concerns regarding bone health, calcium and vitamin D have received the most attention, but there is increasing evidence that the acid/base balance of the diet is also important.’

Average older adults consume diets that, when metabolised, add acid to the body. With aging, we become less able to excrete the acid. One way the body may counteract the acid from our diets is through bone resorption, a process by which bones are broken down to release minerals such as calcium, phosphates, and alkaline (basic) salts into the blood. Unfortunately, increased bone resorption leads to declines in bone mass and increases in fracture risk.

‘When fruits and vegetables are metabolised they add bicarbonate, an alkaline compound, to the body,’ said Dr. Dawson Hughes. ‘Our study found that bicarbonate had a favourable effect on bone resorption and calcium excretion. This suggests that increasing the alkali content of the diet may attenuate bone loss in healthy older adults.’

In this study, 171 men and women aged 50 and older were randomised to receive placebo or doses of either: potassium bicarbonate, sodium bicarbonate, or potassium chloride for 3 months. ‘We demonstrated that adding alkali in pill form reduced bone resorption and reduced the losses of calcium in the urine over a 3-month period,’ said Dr. Dawson-Hughes. ‘This intervention warrants further investigation as a safe and well tolerated supplement to reduce bone loss and fracture risk in older men and women.

Is the GI a key to unlocking a hidden addiction?
Doing something about the obesity epidemic is at the top of most public health agendas. Talk about budget blow out! The financial cost to the whole community of burgeoning waistlines is scary. New Zealand scientists from the University of Auckland explore the idea in Medical Hypotheses that addiction could be an important factor causing the obesity epidemic. They compare and contrast the evidence about nicotine addiction to food and GI and suggest that if high GI foods like corn flakes or white bread are the villain of the piece, ‘low GI equivalents may be the saviour’. The point of the study is really the public health implications of the theory. As the researchers point out: ‘Just as tax increases and control of advertising have proved effective in reducing the prevalence of smoking, similar strategies may help reduce the obesity epidemic.’

Dr Simon Thornley

Lead researcher Dr Simon Thornley, from Auckland Regional Public Health Service, said foods with a high GI caused blood glucose levels to spike, and this rush stimulates the same areas of the brain associated with addiction to nicotine and other drugs. He reports evidence showing that people who binged on high GI carb foods experienced loss of control, a compulsion to keep taking higher amounts to get the same ‘buzz’, and suffered withdrawal if they went ‘cold turkey’.

‘It’s a novel idea that draws on strong evidence that glucose consumption influences levels of the feel-good chemical serotonin in the brain, says Sydney University’s Prof Jennie Brand Miller. ‘Although all foods take about 30 minutes to peak and the overall shape of the post-meal glycemia curve is similar for high, medium and low GI foods, high-GI foods peak and fall at substantially greater levels. Our recent study that explored the association between a food’s GI and the shape of the curve clearly suggests that to control high blood glucose after meals, carb quality (or its GI) and carb quantity both count (see the abstract). So the general message is say “low GI” with carb-rich foods as well as watching portion size.’

For more information about the ‘hidden addiction’ hypothesis email Simon Thornley.

What’s New?

The Giveaway is now closed. Thanks for all the entries to the Shopper’s Guide Giveaway. The winners will be notified by the publishers.

Healthy Indian Cooking for Diabetes
By Azmina Govindji and Sanjeev Kapoor
Published by Kyle Cathie in association with Diabetes UK
There’s no compromising on taste in this book of healthy traditional Indian dishes for people with type 2 diabetes. Dietitian Azmina Govindji and celebrity chef Sanjeev Kapoor address the serious problem of diabetes in the South Asian population (almost 20 million people are affected) with a unique book that provides dietary advice and 100 authentic recipes to help people with diabetes manage their blood glucose with the right foods, portion control and healthy cooking methods. Over the next few months, GI News will be sharing Azmina and Sanjeev’s recipes with readers.

For more information visit www.govindjinutrition.com

Australian Lifestyle Medicine Association Conference
The aims of the first annual conference are to:

• Provide education in the practice of lifestyle medicine to health professionals;
• Inform delegates of the latest scientific findings in lifestyle related health;
• Initiate best practice for financial involvement in lifestyle medicine.

Check the website for details: www.alma-inc.com.au

When? 20-22 March 2009
Where? Manly Pacific Hotel, Sydney NSW Australia
Further information: Troy Grogan (troy.grogan@greatestasset.org)