When you read the article, you'll see the term grey flour used. If you're curious what grey flour actually is, read on...

Grey flour, aka Type 150 is a high extraction flour that contains the germ and much of the bran of a wheat kernel. It has a high ash content - above 1.4. (Ash content is, in part, a method of measuring how much of the bran is included in the flour). See www.theartisan.net/flour_classification_of.htm (scroll down). Hamelman's book also has an interesting section on wheat and milling.

One of the comments below the article has this paragraph:

"One of the great British and Health Food movement myths (and falsehoods) is that whole wheat bread is healthier and more nutritious. It does CONTAIN more nutrients, but less are AVAILABLE, because the bran contains chemicals that prevent absorption of them. In addition, wheat bran is an irritant to the bowel. Far from aiding 'regularity' it is like taking a chemical laxative. "

The writer goes on to say that the grey flour, with less bran, is thus better for you than the whole grain.

Can anyone confirm or belie this allegation?

Rosalie

I've learned this from Hamelman's book. He describes nutrient availability in whole wheat flours and the relationship with sourdoughs in the section about flours and such.

There are lots of nutrients, primarily minerals I believe, contained in the wheat's bran layer, but very little are available for absorbtion by the digestive system. The reason is the prevalence of phytic acid in the bran, which limits absorption of minerals but also, i've recently found out, acts as an antioxidant and has other health benefits. So in this case, yes whole wheat does contain more nutrients, and yes, they are less available to the body, though the culprit also has some health perks.

Hamelman notes that the trick to unlocking the minerals and such in the bran is the sourdough culture. He claims that organisms in the culture, specifically the bacteria if I remember correctly, break down phytic acid in the flour, freeing the minerals to be absorbed.

As for wheat bran being an irritant...I suppose if you were eating whole, unground wheat husks they would probably be very irritating...but as far as I know, there is a vast amount of knowledge about insoluble fibers such as wheat bran and their benefits for colon and overall digestive system health. Maybe there are conditions that cause some reactions to wheat bran presence? Maybe the slightly lower amount of bran in high extraction flour makes it easier to digest because there is less indigestible material in it?

Maggie Glezer also says our bodies are not able to process all the vitamins in whole wheat and so it ends up being a wash, nutritionally, with white flour but I cannot find the page where she states it in ABAA. 

I have heard that whole wheat and rye flours take longer for the body to digest and this is a benefit to diabetics but I’ve never studied this stuff.

Interesting article, Andrew.  I think often these things are simply repeated rather than someone actually studying the truth of the matter and learning what the facts truly are.  It would be worth finding out more information – who is right?  While I enjoy whole wheat breads I prefer the flavor of bread made using a fair amount of white flour so then I could truly eat more white bread with less guilt.  :o)

While not a nutrition faddist, I do have a normal interest in the nutritional value of the food I purchase.

Anyone interested in a nutritional comparison of flour and grains can download this Adobe Acrobat Reader publication published by the USDA www.nal.usda.gov/fnic/foodcomp/Data/SR18/reports/sr18fg20.pdf. This publication is part of the USDA National Nutrient Database. Information on searching and using this database can be found at www.nal.usda.gov/fnic/foodcomp/Data/

Whole wheat flour contains vitamins and minerals that are absent in unfortified white flour. Most naturally occuring vitamins in grain are concentrated in the germ, while naturally occuring minerals are concentrated in the bran. In the US, all white flour must be fortified with certain synthetic B vitamins to replace what is lost by the removal of the bran and germ from flour - read the Nutritional Information on any bag of white flour to see what they are.

This federal mandate was put in place in the mid 1940s in response to long-term observations of nutritional deficiencies in the population consequent on the switch to refined white flour, which had occured several generations prior. Later, folic acid was included in these required additives.

For centuries, people in Europe favored bread made from a wheat flour where much of the bran was removed and the remaining bran was very finely pulverized. Prior to the modern switch to high-speed roller mills, bran removal was difficult to achieve. The process required repeated sifting (aka "bolting") and milling of the flour, so only the very rich could afford to use this lighter flour for their daily bread.

The first step in modern milling is to remove the bran and germ, leaving only the endosperm to be used for flour. The removal of the germ is especially profitable as flour lacking the germ has a much longer shelf life and does not require special storage conditions. Most of the removed bran and germ is processed for animal feed.

Don't forget about fiber-- the difference between taking a chemical laxative and eating fiber-rich foods like wheat bran has everything to do with the indigestible material. The fiber also slows how the eater metabolizes the bread-- bread with more bran and germ will metabolize more slowly and steadily, so you'll have more energy over a longer period of time. White bread will more likely spike your blood sugar and then drop off, leaving you tired or hungry.

I think the loaf's density affects this too, although I've never seen any authoritative information on this. If this is the case, and I think it stands to reason, then a crusty bread may be more slowly metabolized than a soft white enriched bread.   

And fiber can be a pretty serious irritant if you rarely eat fiber. A co-worker of mine has diverticulitis-- he thinks years of processed foods are a pretty major factor-- and can eat virtually no fiber without massive abdominal pain and possibly hospitalization... If you don't like whole-wheat bread, this doesn't sound bad, right? How about no fruits or vegetables? He said he never imagined he'd miss the things he can't eat until he genuinely couldn't eat them.  For a good thing about diverticulitis and diverticulosis, an often-undiagnosed and symptom-free condition which precedes it, check out this site:

http://www.everydiet.org/diverticulitis.htm

Basically, not getting enough fiber will compromise the strength of your digestive system over time and as you age you'll be able to eat fewer and fewer foods. I am a young man (~30) and I love to eat-- only being able to eat a handful of different things strikes me as something of a curse. 

Zolablue,

 I don't know if the whole wheat vs. white flour thing is mentioned in ABAA, but I do think Nancy Silverton mentions it in the intro of her book.

Zolablue,

 I don't know if the whole wheat vs. white flour thing is mentioned in ABAA, but I do think Nancy Silverton mentions it in the intro of her book.