1 September 2010

News Briefs

Wanted! Low GI fast food choices
Carmel Smart's study in Diabetes Care reported that swapping high GI for low GI carbs in 4 healthy breakfast options brought additional benefits for children and teenagers with type 1 diabetes on multiple daily injections and helped reduce post-meal hyperglycemia. What happens, however, when young people with type 1 take their pick from typical food hall lunchtime takeaway offerings?

A study published in the International Journal of Clinical Practice that looked at the glycemic effects of popular takeaway meals reports that it’s not just the quantity of carbs that counts when adjusting insulin dosages, the GI and fat content matters too. In the University of Newcastle study, 9 young adults (average age 23) with type 1 diabetes (all on intensive insulin therapy) tucked into 4 typical lunchtime takeaway meals available in any food hall on 4 different occasions at least 3 days apart. The meals had the same amount of carbohydrate (about 60 grams) but different amounts of fat and protein and low, moderate and high GIs. The meals were:

  • Spaghetti carbonara – low GI/high fat
  • McDonald's Quarter Pounder with fries (fries reduced by 40% to stay within the 60 grams carb limit) – Moderate GI/high fat
  • Thai chicken and cashew stir fry with jasmine rice – high GI/low fat
  • Cheese, ham and tomato sandwich – low GI/low fat
At the 3-hour post-meal mark, all participants had had a significantly lower glycemic response to the low GI pasta meal compared with the Thai, sandwich and hamburger meals. In their conclusion, the authors write: ‘promotion of low GI, low fat fast food choices to young people with type 1 diabetes may reduce postprandial glucose excursions, reduce HbA1c and reduce cardiovascular risk.’ Talking to GI News, lead author Dr Julia Lowe also advises a glucose test after eating low GI/high fat meals, as they may carry an increased risk of the dreaded ‘hypo.’

Will you have a statin with that?
A study published in the American Journal of Cardiology argues the case for handing out free cholesterol-lowering statin drugs whenever you buy fast food to cancel out the health risks of high fat food and provide us with cardiovascular benefits. ‘It is difficult to know how seriously to take this study’ write the reviewers at NHS Choices.‘... junk food has many negative health consequences beyond just increasing cholesterol. Taking a statin pill while continuing with an unhealthy diet will not address all of these. Most importantly, statins are designed for longer-term use under medical supervision. They should not be dished out like ketchup.’

Gut reactions
An Italian study published in Proceedings of the National Academy of Sciences compared the gut bacteria from children in Italy following a Western diet (they don’t tell us what the children actually ate) to children from a village in Bukina Faso, Africa, who followed a traditional African farming diet that was richer in fibre. ‘This study did not follow up the health consequences of the different types of bacteria found in the children and did not directly assess whether there is a link between a particular type of bacteria and illness, allergies or obesity,’ report the reviewers at NHS Choices.‘This study indicates that different diets around the world may have resulted in a different distribution of bacteria found in the gut in different populations. The researchers emphasise that looking further at these distributions may help us to understand which illnesses are diet-related and the role that bacteria play in the promotion and prevention of disease. However, at this point it does not provide evidence linking one type of diet to any illness.’

Lower (45%) carb diet helps weight loss
Obese women with insulin resistance lost a little more weight after 12 weeks on a lower carb, higher fat diet than on a traditional low fat, high carb diet with the same number of calories according to a Jenny Craig-funded study presented at The Endocrine Society’s 92nd Annual Meeting in San Diego.

The researchers randomised 45 insulin-resistant women to a low fat diet or a lower carb diet and provided them with prepared calorie-controlled meals as part of a behavioral weight loss program. The low fat diet consisted of 60% of calories from carbs, 20% from fat and 20% from protein. The lower carb diet held the protein calories at 20%, but cut the carbs back to 45% (a pretty typical amount for many Australians in fact) and upped the fat to 35% primarily from unsaturated fats such as nuts. The daily menus included a minimum of 2 fruits and 3 vegetable servings. Both groups lost weight at each monthly weigh-in, but by 12 weeks, the lower carb dieters lost about 3 pounds more than the low fat dieters (19.6 pounds/9.3kg versus 16.2 pounds/7.3kg). – Source ScienceDaily as the study is not yet published.

Low carb or low fat for weight loss? The choice is yours if you can stick to it
A new study published in Annals of Internal Medicine reports that after 2 years, low fat or low carb dieters taking part in a behavioral program to help them change their lifestyle can both achieve successful weight loss. Both groups in this study lost on average 7kg or 7% of their body weight. A low carb diet may modestly improve some, but not all, risk factors for heart disease, though the researchers report that it is unknown whether these improvements will influence the future development of heart disease.

The study included 307 obese men and women. The low carb diet group was instructed to eat no more than 20 grams of carbohydrate per day for 3 months and then increase that by 5 grams a day each week until they achieved their desired weight. The low fat diet group were told to decrease their calorie intake to 1200–1800 calories a day with no more than 30% of calories from fat. All took part in the education program that met weekly for the first 20 weeks, then every other week for 20 weeks, and then monthly for the rest of the 2-year study to help them increase their physical activity and change their lifestyle. Many participants did not last the course on this study.

3 comments:

Anonymous said...

Why did many participants not last the course?

Dr. Eric Berg Healthy Weight Loss Diet Plan said...

I'm also curious about it. If its safe and effective, why did they not last long? Is there something wrong?

GI Group said...

If you want to know more about this study, you need to contact the researchers. The email address for the lead researcher as given in the abstract link in our report is: gfoster@temple.edu.