Monday, November 24, 2008

A good week for nutrition news

We all love to read good things about foods we love but we know, deep down, are not really nutritious (yes, me too). As a vegan, I also enjoy reading things about foods that people justify, over and over, as healthful and appropriate, when we all know that regular consumption of these foods is the foundation of chronic disease. The more evidence that piles up against the consumption of animal products, the bigger push there will be towards the general acceptance of plant-based diets.

This month, the journal Diabetes Care (click here for the abstract) published a study by Harvard researchers who reported that people who eat eggs daily may substantially increase their risk of type 2 diabetes.

According to the study, this is the first time researchers investigated this particular connection. The study was funded by the National Cancer Institute and the National Heart, Lung, and Blood Institute; no conflict of interest has been reported.

The study analyzed the eating habits of 57,000 people (a combination of the Physician's Health Study and the Women's Health Study) and concluded that men and women with the highest level of egg consumption (one a day or more) were 58% more likely and 77% more likely, respectively, to develop type 2 diabetes than those who did not eat eggs.

That's pretty impressive. Sometimes study results can be attributed to chance or confounding variables. With numbers this high (57,000 subjects) and the effect this strong, it's highly unlikely that these results are not real. Of course, correlation is not necessarily causation, so the effect may not be quite this strong, and of course not generalizable to everybody. Some alternate explanations for the reported observations include (per the lead researchers): First, the data did not include repeat fasting glucose, fasting insulin, and other biomarkers of glucose metabolism to comprehensively examine possible physiologic mechanisms. Second, he observational studies may also have been limited by self-reporting and residual confounding, Third, the generalizability may have been limited as well by the homogeneous, primarily Caucasian health professional population, which may have different behaviors than the general population (reference).

In other news, a recent Dutch study presented at a recent American Heart Association Meeting reports that all trans fats -- regardless of its source -- raise blood cholesterol levels. (Click here for more details.) This is an important finding because historically, nutrition professionals have warned against the trans fats that are manufactured as a result of hydrogenation of fat (listed on a label as "partially hydrogenated oil" -- found mainly in processed foods like crackers, cookies, and condiments), essentially ignoring the contribution of naturally-occurring trans fat, that is, trans fat found in dairy products and meat. Most people aren't even aware that animal products are a natural source of these damaging fats. The amount of trans fats in a typical serving of meat or dairy is relatively low, but over time the amounts do add up and are indeed significant. Add yet another reason to follow a primarily (or exclusively) plant-based diet.

1 comment:

Paulina said...

I'm so glad you blogged about this! I've always known that trans-fat is super bad for you and I've tried explaining to my mom why I won't go near anything that has even a trace of the stuff but she doesn't understand. Reading labels and paying attention to ingredients is just not her thing. Oh well, hopefully one day she'll listen to me.