1 May 2013

What’s New?

Canada’s new diabetes guidelines recommend low GI carbs. 
The online release the Canadian Diabetes Association includes the full text of all 38 chapters and an appendix. Each chapter comes with a slide set and a brief video highlighting the key recommendations. There are also accompanying tools for health care providers and resources for patients. Here are the Key Nutrition Therapy Messages:

  • People with diabetes should receive nutrition counselling by a registered dietitian. 
  • Nutrition therapy can reduce glycated hemoglobin (HbA1C) by 1.0% to 2.0% and, when used with other components of diabetes care, can further improve clinical and metabolic outcomes. 
  • Reduced caloric intake to achieve and maintain a healthier body weight should be a treatment goal for people with diabetes who are overweight or obese. 
  • The macronutrient distribution is flexible within recommended ranges and will depend on individual treatment goals and preferences. 
  • Replacing high glycemic index carbohydrates with low glycemic index carbohydrates in mixed meals has a clinically significant benefit for glycemic control in people with type 1 and type 2 diabetes. 
  • Intensive lifestyle interventions in people with type 2 diabetes can produce improvements in weight management, fitness, glycemic control and cardiovascular risk factors. 
  • A variety of dietary patterns and specific foods have been shown to be of benefit in people with type 2 diabetes. 
  • Consistency in carbohydrate intake and in spacing and regularity in meal consumption may help control blood glucose and weight. 
The guidelines are accessible here.

Low carb diets don’t help women with gestational diabetes
Dr Kate Marsh of Northside Nutrition and Dietetics and co-author (with Prof Jennie Brand-Miller) of The Low GI Eating Plan for an Optimal Pregnancy comments on a recent study in Diabetes Care that has shown that a low carb diet in women with gestational diabetes didn’t reduce the number of women needing insulin or affect pregnancy outcomes.

Kate Marsh
Dr Kate Marsh

‘Carbohydrate foods (e.g. breads, cereals, grains, rice, pasta, legumes, starchy vegetables, fruit, milk and yoghurt) break down to glucose and directly affect blood glucose levels. For women diagnosed with gestational diabetes during their pregnancy, eating the right amount and types of carbs is therefore essential for keeping blood glucose levels in the target range. While some women may think that just cutting down on carbs is the answer, this new study has shown that a low carb diet in women with GDM didn’t reduce the number of women needing insulin. Many carbohydrate foods (e.g. wholegrains, fruit and dairy) are important in helping to meet nutritional needs during pregnancy, and very low carbohydrate intakes during pregnancy can be detrimental to a growing baby. Previous research has shown that a low GI diet (where carbohydrate intake is similar but the types of carbs are changed to lower GI options) can reduce insulin requirements in women with GDM, which in conjunction with these latest findings suggests that choosing the right carbs rather than necessarily cutting down carbs (unless intake is particularly high), is the key to managing blood glucose levels in pregnancy.’

Low carb diets? Not for the long haul.
A growing body of evidence suggests that low-carb diets and their combination with high-protein diets are effective in weight loss – they are certainly popular. In addition, they may have favourable short-term effects on risk factors of cardiovascular disease. However, it now seems there could be serious health implications if people consume a low-carb diet for a long period of time. When Hiroshi Noto and his co-authors, from the University of Japan reviewed 17 long-term studies into low carb diets published in PLOS ONE, they found that low-carb diets were in fact associated with a significantly higher risk of all-cause mortality. ‘Low-carbohydrate diets tend to result in reduced intake of fibre and fruits and increased intake of protein from animal sources, cholesterol and saturated fat. In their conclusion they write: ‘Our meta-analysis supported long-term harm and no cardiovascular protection with low-carbohydrate diets. … Our findings underscore the imminent need for large-scale trials on the complex interactions between low-carbohydrate diets and long-term outcomes.’

Cuba: how an economic downturn lead to a health upturn.
A recent study in the BMJ suggests that initiatives that encourage people to eat less and exercise more could achieve significant positive health outcomes. The findings are based on the Cuban experience in 1980–2010. During the early 1990s, Cuba suffered an economic downturn due to a tight US embargo on imports and the collapse of the Soviet Union, which had been supporting the country. This led to a drop in the number of calories consumed in the average Cuban diet. Due to the embargo, petrol became virtually unobtainable, and more than 1 million bicycles were distributed by the government, leading to an increase in physical activity. These factors contributed to an average weight reduction per citizen of 5.5kg over the course of the five-year economic crisis. During this time there was a significant drop in prevalence of, and deaths due to, cardiovascular diseases, type 2 diabetes and cancers. But once the crisis was over and people started to eat more and exercise less, these trends began to reverse. The question is how, in an affluent and free Western democracy, do you encourage people to eat less and exercise more?

Bicycling in Cuba

Commenting on this study, Prof Walter Willet writes: ‘Physicians can help promote healthy social norms by visibly engaging in healthy behaviors. On a recent trip to Cuba, I had hoped to see Havana by borrowing one of the million bicycles that had been distributed. However, there were virtually no bikes, bike riders, or bicycle lanes to be seen; and several people told me that bicycles reminded them of earlier economic hardships. In many countries, walking and bicycle riding are regarded as lower class behaviors. Boston celebrates the example set by Paul Dudley White, probably the most famous cardiologist in America and personal physician to President Eisenhower, who rode his bicycle daily to Massachusetts General Hospital into his 80s. The city named a bike path in his honor, and it is currently expanding its bicycle parking facilities. Dr White may have saved more lives by his bike riding than by putting stethoscope to flesh.’

The Low GI Eating Plan for an Optimal Pregnancy. 
The Low GI Eating Plan for an Optimal Pregnancy (The Experiment Publishing) helps a mom-to-be understand the connection between the food she eats, her blood glucose levels, and her baby’s future health. The focus is on low GI carbohydrates – vital at this time, because reducing dietary GI is one of the safest and most effective ways to ensure that baby grows at the optimal rate, without mom gaining excessive body fat and without compromising nutrition. One of the authors, Prof Jennie Brand-Miller, explains why: ‘Pregnancy is a stage in life when carbs play a starring role. This is because a Mom’s average blood glucose level throughout the day is directly correlated with her baby’s growth rate in the womb. Quite simply, glucose is the primary fuel that drives all aspects of her baby’s development. If her glucose levels are too high, then her baby will grow too fast and be born with excessive amounts of body fat. Conversely, if her glucose levels are too low, baby’s growth might be too slow.’

Kate Marsh
– Published in Australia in 2012 as The Bump to Baby Diet.

Online updates.
#1 Here's a blog that’s just the recipe for women with GDM After having gestational diabetes (GDM), Lisa Taylor created the Gestational Diabetes Recipes website with dietitian Natasha Jo Leader because she loves food. With this recipe blog, she hopes women are able to turn their diagnosis of GDM into a more positive experience that allows them to continue to enjoy delicious food and their pregnancy but be mindful of the importance of healthy eating and lifestyle for the long term for both themselves and their children. You can try Lisa’s recipes here.
#2 Having worked as an author, food editor, writer, consultant, teacher and publisher for some 23 years, Low GI Family Cookbook co-author, Anneka Manning, has now started the BakeClub. This is a cooking school where you can learn to create baked goodies online or by attending classes and workshops. Classes start in May in Sydney, Australia. First up (11 May) is a three-hour workshop on creating snacks for healthy kid’s lunch boxes (and for after school, too). In the workshop, store-bought muffins, muesli bars, biscuits and cakes will be compared with healthier, more natural home-baked versions then you learn how easy it is to fill lunch boxes with these ‘better for you’ sweet and savory alternatives, that you will feel good about and your kids (and their friends) will enjoy. You can find out more about this workshop here.

Anneka Manning
Anneka Manning