Fuelling willpower with glucose.
At a time of year when many people are resolving to go on a diet, we thought we’d remind readers that willpower seems to be affected by the brain’s glucose supplies – so don’t skip meals. Self-control requires a certain amount of glucose to operate unimpaired. Writing in the Journal of Personality and Social Psychology Matthew Gailliot and researchers from Florida State University found that even relatively small acts of self control are sufficient to deplete the brain’s available supply of glucose thereby impairing the control of thought and behavior, at least until your body can retrieve more glucose from its stores or you have something to eat. Their laboratory tests with volunteers found that:
- Acts of self-control reduced blood glucose levels
- Low levels of blood glucose after an initial self-control task predicted poor performance on a subsequent self-control task
- Initial acts of self-control impaired performance on subsequent self-control tasks, but consuming a glucose drink eliminated these impairments.
The Florida study involved numerous tests but a key one found that people who drank a glass of regular lemonade (i.e. sweetened with sugar) between one task requiring self control before beginning a second also requiring a fair bit of willpower performed equally well on both tasks, while people who drank a ‘diet’ lemonade in between made more errors on the second task than on the first. They used sugar in their studies because it is fast acting and convenient, but make the point that ‘complex carbohydrates may be more effective for sustained self control.’ Research in memory tests has certainly shown that low GI carbs enhance learning and memory more than high GI carbs, probably because there is no rebound fall in blood glucose.
Diet quality a good guide in stroke prevention.
Professor Graeme Hankey
‘While we have seen a reduction in incidence of stroke and mortality in the past 20 to 30 years due to better control of blood pressure and smoking we are seeing a deceleration in that decline,’ says Prof Graeme Hankey head of Royal Perth Hospital’s stroke unit. ‘We are seeing the emergence of the beginning of a trend to increases in stroke incidence because all our kids are overweight and not exercising and we are seeing strokes in young people as diabetes and metabolic syndrome take over.’
The overall quality of a person’s diet and the amount of food they eat rather than individual foods and nutrients is a better guide to whether he or she will suffer a stroke he says in his review of a raft of international studies on risk factors for stroke in Lancet Neurology. Weighing up the evidence he says:
- Poor nutrition in the first year of a mother’s life and undernutrition in utero, infancy, childhood, and adulthood predispose individuals to stroke in later life, but the mechanism of increased stroke risk is unclear.
- Reliable evidence suggests that dietary supplementation with antioxidant vitamins, B vitamins, and calcium does not reduce the risk of stroke.
- Less reliable evidence suggests that stroke can be prevented by diets that are prudent, aligned to the Mediterranean or DASH diets, low in salt and added sugars, high in potassium, and meet, but do not exceed, energy requirements.
Many of Prof Jennie Brand-Miller's low GI books are now available as eBooks from online retailers in Australia, the US and Canada and the UK including Amazon, Apple, ebooks.com, Google Books and Kobo.
Australia/New Zealand/UK editions (Hachette) now available
- Low GI Diet Handbook – ISBN 9780733628078
- Low GI Diet Shopper’s Guide 2012 – ISBN 9780733628559
- Low GI Diet 12-week Weight-loss Plan – ISBN 9780733627781
- Low GI Diet for Childhood Diabetes – ISBN 9780733628221
- Low GI Diet for Polycystic Ovarian Syndrome – ISBN 9780733628375
- Low GI Handbook – 9780738214139
- Low GI Shopper's Guide to GI Values 2012 – 9780738215211
- Low GI Diet Revolution: The Definitive Science-Based Weight Loss Plan – 9780786727803
- New Glucose Revolution for Diabetes – 9780786751341
- New Glucose Revolution Low GI Gluten-Free Eating Made Easy – 9780786746538
- Low GI Guide to Living Well with PCOS – 9780738214498
Learn to love lentils and you’ll have a deliciously natural low GI diet and a great ingredient for ‘Meatless Mondays’. Now an enterprising pair up in the stunning hinterland of beautiful Byron Bay has made it really easy for everyone to learn to love lentils. Back in 2009, Anthea Packshaw and Sharna Glasser started their Lentilicious business and they have been enthusiastically making and marketing their range of five flavoured, pre-packed lentil meals that include herbs, spices and other flavourings ever since. The Lentilicious range of flavours includes Coconut Fusion, Lime Time, Mediterranean, Turmeric Magic and Red Chilli. All you need to do is tip the lentils into a saucepan, add cold water, bring to the boil then simmer gently for 25 minutes and the meal is ready. Each package serves 2–3 people.
The Lentilicious story Sharna and Anthea met while working at a resource centre in Mullumbimby. Passionate about vegetarian cuisine and inspired by traditional Indian dahl, they set about creating a range of delicious, modern lentil meals designed to make lentils mainstream. You can find out more about Lentilicious here.