Tuesday, August 10, 2010

Another reason to avoid Wonder Bread.

As if you needed another.

Straightforward study that explored the impact of the great social experiment in which the past 40 years of low-fat recommendations have placed us.

The study looks at the risk of having a heart attack as a function of macronutrients in 57,053 Danes over a 12 year period and then re-analyzes risk on the basis of the glycemic indices of their carbohydrate choices.

The researchers used two models to investigate the risk of heart attack with a higher energy intake from carbohydrates and a concomitant lower energy intake from saturated fats (just like what we're still being told to do by national dietary guidelines, health organization and health related NGOs). The first model looked at macronutrients as a percentage of total energy intake. The second model further subdivided the carbohydrates into tertiles of dietary glycemic index. Both models controlled for alcohol intake, smoking status, physical activity and hypertension.

The results probably won't surprise you.

Folks who replaced saturated fats with high glycemic index carbohydrates (Wonder Bread for instance), had a statistically significant increase in their risk of heart attack, and while not statistically significant, replacing saturated fats with low glycemic index carbs appeared protective.

What's surprising to me aren't these results but rather the fact that the blind low-fat message is still being put out there by governments and health organizations who if they don't know better, certainly should.

What we should be telling folks to do is substitute healthy fats for unhealthy ones and perhaps more importantly, telling folks to substitute low glycemic index carbohydrates for high (or more simply put, whole for refined).

Jakobsen, M., Dethlefsen, C., Joensen, A., Stegger, J., Tjonneland, A., Schmidt, E., & Overvad, K. (2010). Intake of carbohydrates compared with intake of saturated fatty acids and risk of myocardial infarction: importance of the glycemic index American Journal of Clinical Nutrition, 91 (6), 1764-1768 DOI: 10.3945/ajcn.2009.29099