Carb Expert Takes On Wheat Misinformation on Discovery.com

Author: 
Julie Miller Jones, PhD
02/11/2013

Noted carbohydrate expert and nutrition educator Julie Miller Jones, Distinguished Scholar and Professor Emerita of nutrition at the St.Catherine University in St. Paul, MN, recently sent the following letter to officials at Discovery.com.

January 25, 2013
David M. Zaslav, President and CEO, Discovery Communications
Bill Goodwyn, President, Global Distribution and CEO, Discovery Education
Discovery
One Discovery Place
Silver Spring, MD 20910
Dear Mr. Zaslav and Mr. Goodwyn:
I am writing to you to express my concerns about the headline and content of your article “Why
You Should Probably Stop Eating Wheat” that appeared as a posting on the Discovery.com
website December 14, authored by George Dvorsky.
The posting begins with a line stating that “Wheat contains a protein that degrades into a
morphine-like compound after eating, and creates an appetite for more.” The actual veracity of
the statement is questionable. The research finding on which this statement is based is a 1979
NIH in vitro study, which tested a few food proteins found not only in wheat but also proteins in
milk, soy, rice and even spinach. These proteins also formed peptides that in cell tissue culture
assays reacted with the opioid receptor. The conclusion of the NIH paper counseled caution
stating that the results of this in vitro study – while interesting -- would need much further study.
Subsequent research from the Institute for Diabetes and Obesity and other laboratories around
the world show that food-derived opioid peptides such as those alluded to in this article cause a
gut-brain feedback that actually results in enhanced satiety, not increased eating (1 -3).
The posting is correct that a growing number of people are switching to wheat-free diets, but is
incorrect in stating that many are doing so for good reason. At most, 7% of the population has a
reason to avoid wheat or gluten because 1% (1 in 133) of the US population has celiac (also
called gluten intolerance), under 0.5% has a wheat allergy, and 3-6% has gluten sensitivity.
Currently, there is a medical basis for 6-7% of the population to avoid wheat. It is not known
whether the 3-6% with gluten sensitivity need to remain gluten free for a lifetime as must those
with celiac. In persons susceptible to celiac disease gluten may trigger an autoimmune response
that results in flattening of the fingerlike projections in the small intestine (villa) that enable the
absorption of all food. These adverse effects on the intestine are only seen in individuals
genetically at risk for developing for celiac and do not cause the increased immune response or
altered mineral absorption in normal individuals as suggested in your article.
It is true that the celiac disease incidence, as well that of other autoimmune diseases, is
increasing but the reasons are unknown. What is known is that there is increased intestinal
permeability, known as gut leakiness. It is simplistic to say that one food or protein causes
intestinal permeability because it has many causes both food- and non-food related. Medical and
body conditions including obesity may result in bacterial overgrowth that can result in
‘leakiness.’ Some suggest that overactive immune system can result because extreme cleanliness
confuses the immune system so it attacks beneficial proteins rather than invaders. Certain fats,
drug treatments, inadequate diets overall, foodborne pathogens and mycotoxins have all been
named as contributors. Pre- and probiotics, fermented dairy products, colostrum and breast milk
with their inulin-like oligosaccharides and beneficial bacteria, antioxidant and anti-inflammatory
components from fruits, vegetables, whole grains, legumes, nuts and seeds, as well as an overall
healthy diet have all been shown to be helpful in reducing bacterial overgrowth and promote
healthy cell junctions in the gut.
Gluten and Plant Breeding
Thank goodness wheat is different than it was 50 years ago because it has enabled feeding of
more of the world population with less land and fewer inputs. So important was this work, that
plant scientist Norman Borlaug was awarded the Nobel Peace Prize. His critical work shifted
grain- importing nations into self –sufficient nations and helped reduce food insecurity in many
parts of the world.
The notion that proteins produced by wheat breeding are unique or novel proteins as claimed is
blatantly untrue. While, plant breeding does try to increase proteins that carry desirable traits, it
cannot generate proteins that were not in the DNA of the parent wheat plants. While it is true
that mutations in DNA sequence are a natural part of evolution, it is not true that modern wheat
varieties are routinely developed with the aid of mutagens, such as sodium azide, as alleged in
the article. This is totally foreign to modern-day wheat breeders. Breeders do select from the
vast array of traits present in wheats from around the globe to produce wheat that will thrive in
diverse, and in some cases sever, climatic conditions.
According to a paper by U.S. Department of Agriculture, Agricultural Research Service, longtime
expert on gluten Dr. Don Kasarda, (5) there simply is no evidence of an increase in gluten
content of wheat during the modern breeding era, starting in the 1920s. Furthermore, the wheat
gluten present in our diet does not represent any systematic shift to certain forms of gluten. In
fact, popular foods demand glutens with differing capabilities in order to produce foods from
gnocchi, to pretzels, to angel food cakes and hearth breads. Thus, a wide range of wheat strains
are sought to yield many types of gluten with differing functional capabilities.
High Glycemic Index
While it is true wheat bread has a high glycemic (GI) index, the values actually vary: the GI of
100% whole wheat bread is 71 with a range from 52-87. If part of the whole wheat bread is
made with 50% cracked wheat kernels, the GI is 58. The GI of white enriched pasta is also in
the mid 50s. Thus, statements that starch patterns in wheat cause a high GI are illogical because
various wheat-based products have different GI values.
Comparing the GI from two slices of whole wheat bread with a candy bar completely ignores the
express purpose of the index to compare foods within a category. However, going from
comparison of whole wheat bread with a candy bar to stating that overconsumption of wheat can
result in "deep visceral fat" is absurd. Data show those who eat 2 servings of whole grains and 3
of refined gains have the least visceral fat tissue and those with greater whole-grain food intake
were associated with lower fasting glucose and insulin concentrations independent of
demographics, other dietary and lifestyle factors (6, 7).
A diet too high in carbohydrate without enough beneficial fat from nuts, avocados and fish does
cause the production of the atherogenic, small low-density lipoprotein (LDL) particles, but this
can happen with any imbalance in carbohydrate/ fat ratios. Any diet that improves the quality of
the fat and moderates carbohydrate intake while maintaining dietary fiber is the best strategy for
impaired glucose tolerance (8).
Lectins and Phytates
It is true that lectins are found in beans/ legumes, cereal grains, and nuts, and some vegetables. It
is also true that when high doses of pure lectin or raw legumes1 are fed to animals, they can show
adverse effects such as binding to blood cells or insulin receptors. However, there is no evidence
that any of these foods when properly cooked increase inflammation and insulin resistance. In
fact epidemiological data show that all of the foods listed are associated with lower rates of
inflammation, diabetes and insulin resistance (9-15).
It is also true that phytates bind metal ions like calcium, magnesium, zinc, and iron and inhibit
their absorption, but during proofing and baking phytases (enzymes that target phytates) decrease
phytates thus reducing the impact on mineral availability (16). What is also true is that phytates
and oxalates found in many vegetables have the same negative impact on mineral metabolism as
wheat is purported to have. No one recommends that people stop eating spinach, soy, or nuts
because of the high oxalate or phytate. Rather, dietary recommendations encourage all of these
foods along with good sources of calcium such as milk and good sources of iron such as that
from heme iron.
The Fiber Myth
The inclusion of cereal fiber in the diet has good basis in fact. Many studies show that cereal
fiber for certain disease endpoints, in contrast to other types, plays a much more important role
(17-21). However, all sources of fiber are needed because of the different roles they play (18),
so fruits, vegetables, grains, nuts and legumes are all important to any diet. In most Western
countries, the sad truth is that the population consumes inadequate amounts of whole grains or
fruits, vegetables, legumes and nuts to address the fiber gap. Under 5% of the U.S. population
meet the fiber requirement (22).
A better idea for an article would be one about the importance of getting more dietary fiber in the
diet through good choices of nutritious whole grain foods, fruits, vegetables nuts and seeds.
These dietary strategies have stood the test of time and need to be applauded and encouraged
rather than undermined by postings, which tout a popular fad and fail to present research that
fully characterizes the subject.
1 Raw kidney beans contain from 20,000 to 70,000 lectin units, while fully cooked beans usually
contain between 200 and 400 units.
Sincerely,
Julie Miller Jones, PhD
4030 Valentine Ct.
Arden Hills, MN 55112
juliemjones@comcast.net
jmjones@stkate.edu
651.636.2275
Dr. Julie Miller Jones is a professor emerita from St. Catherine University in St. Paul Minnesota,
where she was a professor for over 35 years. She is the author of several books and many papers
and has recently completed a critical scientific review of statements in the book Wheat Belly.
She has received many honors including being named an Academic Fellow of the International
Cereal Chemists and honorary member of the Grains for Health Foundation. She is the scientific
advisor to many groups including the International Life Sciences Institute, the Wheat Foods
Council, the Grains Foods Foundation and the Joint Institute of Food Safety and Nutrition of the
U.S. Food and Drug Administration and the University of Maryland.
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