Tuesday, November 3, 2009

I'm deficient, You're deficient, We're all deficient? (Part 1)

I was recently reading a press release from Nature's Path Organic about two of their new cereals (that product review is forthcoming...). The press release made a familiar argument: the cereals "provide gluten avoiders with whole grains... unlike many gluten-free cereals which forfeit nutritional benefits..." The implication is that many gluten-free cereals (and other gluten-free processed foods, by extension) are more highly processed in order to improve taste and texture. But they do so by sacrificing nutritional quality.

There is some truth to this logic. Foods made from whole grains are inherently healthier than heavily processed foods, and I'll use our good old enemy - wheat - to demonstrate. I compared whole grain wheat flour (less processed) with white, unenriched wheat flour (more processed) across a range of nutrient measures. Not surprisingly, the wheat underwent a profound loss in nutrient quality when it was processed (I've omitted the units of measure for clarity):

NutrientWhole GrainWhite Unenriched

These values come from the USDA's National Nutrient Database for Standard Reference, and the important thing is to notice the marked decline in nutritive value. We might reasonably conclude the same kind of trend with gluten-free whole grains foods versus those that have been highly processed. (Side note: this is just one reason why I'm wary of some of the new gluten-free foods on the market, such as Expandex, a modified tapioca starch.)

This specific example reminded me of a report earlier this summer announcing that people on a gluten-free diet are quite often nutrient deficient. Heavily processed GF foods were partly to blame. The report came from research conducted at the Celiac Disease Center of Beth Isreal Deaconess Medical Center in Boston. The announcement came at the annual Digestive Disease Week conference, and caused quite a stir in the GF community. I haven't been to find officially published results of the study, but one of the attendees at the conference thankfully posted some of the findings.

The study looked at a three-day period in the diets of 109 men and women from the Boston area, all of whom were diagnosed Celiacs, and all of whom were reportedly on a GF diet for at least 5 years. At first blush, the results seemed pretty profound (I've rounded to the nearest whole percentage point):

NutrientPercent Deficient

But almost immediately, several thoughts and questions popped up in my mind. 1) 109 people seems an awfully small sample pool. This blog alone has many more readers than that. If each one of us kept a detailed dietary journal for three days, we've have a more robust pool of data than the researchers.

2) As far as I know, the researchers didn't make distinctions within the GF population. However, I think that's a mistake. Personally, I'd break out the pool into three categories: a) folks on a GF analog of the standard American diet, with a high percentage of heavily processed foods; b) folks on a GF diet that incorporates more whole grains, including alternative and "ancient" grains becoming popular within GF circles today; and c) folks on a GF diet heavy in fresh fruits and vegetables, as well as whole meats and fish. In practice, we're all - to greater and lesser degrees - some combination of those three types. But I think you'd see a measureable difference in nutrient deficiency between them.

3) How did the nutrient deficiencies of the GF population compare to the average American? Were we more nutrient deficient? The same? Perhaps even less? The results on their own seemed out of context without comparison to some baseline.

4) Was the nutrient deficiency an actual result of the gluten-free diet, or was there another contributing factor? Was it the standard American diet that was to blame, and not the gluten-free aspect of the diet? Was it not the diet, but rather the person? Said another way, was it a case perhaps of nutrient malabsorption, because of damaged villi in the small intestine? In such an instance, you might eat all the right things, but those nutrients would just pass on by without being absorbed into the body.

I set out to find answers to those questions. Coming tomorrow...what I found.

- Pete


Joe said...

awesome. i am excited to see the results. i am only 19 years old and new to this blog. i am lucky to have found out early about celiac and also have people like you out there doing community favors. your writing, recipes, and blog are greatly appreciated!

- joe

peterbronski said...

Hi Joe... Welcome to NGNP! Glad you're enjoying the posts. If you ever have any questions not answered on the blog, don't hesitate to contact me.

Cheers, Pete

gfe--gluten free easily said...

This and part 2 show what I've always said, you can be just about as unhealthy eating gluten free if you are eating processed gluten-free specialty foods as you were before when you were eating gluten. That sounds extreme, but if most of our diet is processed and refined flour, starches, and gums, that's not good for sure. Always good info here, Pete! Thanks!


peterbronski said...

Hi Shirley... Yes, all roads lead to whole, fresh, natural foods! The explosion in GF specialty products is both a blessing and a curse. Part of me wishes more people in the GF community were forced to abandon the processed food...

Cheers, Pete