This study belongs in the “how did it get published” category.
Yes, you read that correctly. Now if you’re scratching your head and wondering how this could be – whether it’s due to factors such as the genetic makeup of those who live in the U.S. or some unique characteristic of Americans – stop wondering.
Here’s an example of how it can sometimes be really important to take nutrition research with a grain of salt. The researchers themselves offer reasons why they may have come to these conclusions and why they may be inaccurate.
First the research.
The study, published in British Journal of Nutrition by experts from Harvard University, the University of Eastern Finland and Mexico’s National Institute of Public Health, analysed the findings from ten different population-based studies from around the world – covering approximately 250,000 people (173,000 women and 77,000 men). Four of these studies were conducted in the US, one was carried out in Japan and the rest took place in Europe. During the studies’ follow-up, approximately 12,000 people developed type 2 diabetes.
The findings showed that every egg added to the daily diet increased the risk of type 2 diabetes by 13%.
But here’s the catch: the increased risk was mainly observed in the four studies conducted in the U.S. while the data from the other countries showed absolutely no link between egg consumption and diabetes.
The authors suggest the American egg-diabetes connection may be due to other factors than eating eggs. In the US studies, for example, eating eggs was often associated with unhealthy lifestyle habits such as smoking, low levels of physical activity, or frequent consumption of processed meat The scientists also had no information as to how the eggs were prepared or eaten – possibly on a plate with plenty of bacon, sides of hash browns or home fries and some buttered white toast. Who knows? But these details would definitely have an impact on diabetes risk.
In other countries, eggs are not associated with these unhealthy behaviours.
The unhealthy lifestyle factors are considered to be what is called confounders in research – those factors which have an impact on the findings and could throw off the study findings. But good research should be able to rule out the effects of these confounders before coming to any conclusions.
Even more confusing as to why this study was published, the scientists point out that, in other research, experimental studies in humans have shown that increased egg intake has instead had a beneficial impact on several risk factors for type 2 diabetes, such as insulin resistance and inflammation.
If this research makes headlines, it will do a disservice to many people. For example, at breakfast, instead of including a nutrition-packed egg – a choice with plenty of protein that can help to tame appetites all day long, someone, who struggles with their weight and is at risk for diabetes, might mistakenly opt for a carb-heavy breakfast minus the egg.
This research is worthwhile hearing about but not for assessing the eggs-diabetes connection. It’s a great lesson in how scientific research can lead to confusion and less than enlightened choices.
Did you hear about this study? What were your thoughts? Please share in the comment section below.