Should you follow a no-grain diet?
The No-Grain diet is based on the idea that grains and sugars are
"enemy number one to losing weight and living longer."
Instead, The No-Grain diet emphasizes organic vegetables and quality
protein.
It's true that refined grains — such as white bread, white
rice and many breakfast cereals — contain many calories, but
without the fiber, vitamins, and minerals found in whole-grains.
In other words, they're energy-dense but nutrient-sparse.
But it's worth pointing out that there's a difference between whole
grains and refined grains.
A good example comes from a study published in the American
Journal of Clinical Nutrition [1]. The results show that middle-aged
women who favor whole grains over white bread and other refined
grains put on fewer pounds as they age.
Harvard researchers found that among 74,000 women, those who ate
more fiber-rich grains — such as oatmeal and whole-grain breakfast
cereals — gained less weight over time than women who got the
least fiber in their diets.
In addition, women with the highest fiber intake were half as likely
as those with the lowest intake to become obese over 12 years. In
contrast, diets heavy in refined-grain products like white bread
and pasta were linked to greater weight gain over time.
While carbohydrates have lately gotten a bad rap in the weight-loss
realm, the new findings underscores the fact that not all carbs
are alike.
Research suggests that when it comes to weight control, whole grains
such as oats, bran and brown rice have an advantage over highly
processed, low-fiber grain products. For one, fiber-rich whole grains
are more filling, and people who favor them over refined grains
may take in fewer calories.
While starchy refined grains cause a rapid increase in blood sugar,
whole grains may create a slower, more sustained release of sugar
into the blood — which may have a beneficial effect on metabolism
and fat storage.
Whole grains also contain enzyme inhibitors that may get in the
way of metabolic efficiency. This means that your body is forced
to burn extra calories just to digest and absorb whole-grain foods.
For their study, the researchers analyzed data from a large, long-running
study of female nurses in the U.S. More than 74,000 women who were
between the ages of 38 and 63 in 1984 periodically gave information
on their diets and weight over the next 12 years. Other factors,
such as exercise and alcohol intake, were also measured.
Women who ate more whole grains tended to weigh less than those
with diets heavier in refined grains. And over time, higher intake
of fiber-rich grains was associated with less weight gain.
On average, women who ate the most high-fiber, whole-grain foods
gained a few pounds less than those with the lowest fiber intake.
They were also less likely to become obese.
Diabetes
Eating whole grain food is also linked to a reduced risk of developing
diabetes [3].
Nicola McKeown and colleagues from several US-based medical and
academic establishments in Boston, Massachusetts and Charleston,
South Carolina collected data from 2,834 subjects in the Framingham
Offspring Cohort, part of the long-running Framingham Heart Study.
The aim was to examine the relationship between carbohydrate-related
dietary factors, insulin and the prevalence of metabolic syndrome.
After adjusting for confounding variables, the results suggested
that intakes of total dietary fibre, cereal fibre, fruit fibre and
whole grains were inversely associated with insulin resistance.
In contrast, glycemic index and glycemic load were positively associated
with insulin resistance (measured as the homeostasis model assessment
of insulin resistance HOMA-IR).
The prevalence of metabolic syndrome was significantly lower in
subjects whose intakes of cereal fibre and whole grains were in
the highest quintile, relative to those with intakes in the lowest
quintile.
Metabolic syndrome is characterised by a group of metabolic risk
factors which are known to be closely associated with the development
of type II diabetes and coronary heart disease.
One of the benefits of whole grains is that they contain important
vitamins and minerals.
Magnesium is just one example.
A research team from the Harvard School of Public Health in Boston
followed the fortunes of 85,060 women and 42,872 men who had no
history of diabetes, cardiovascular disease or cancer at baseline
[2].
Magnesium intake was estimated using food frequency questionnaires
every 2-4 years over follow-up periods of 18 years for the women
and 12 years for the men.
After adjusting for age, body mass index, smoking, alcohol consumption
and other lifestyle factors, the data showed that men and women
whose diets contained the highest amounts of magnesium (from whole
grains, nuts and green leafy vegetables) were the least likely to
develop type II diabetes.
A second study using data from 39,345 women in the Women’s
Health Study at Brigham and Women’s Hospital and the Harvard
Medical School in Boston, found that a high dietary intake of magnesium
improved glucose and insulin homeostasis, and reduced the likelihood
of developing type 2 diabetes, especially in overweight women [4].
Further evidence linking refined grains and weight gain comes from
a Tufts University study. The research shows that regular consumption
of white bread and other foods made from refined flour adds inches
to the waistline.
Participants in the study who favored white bread actually gained
a disproportionate amount of weight in the abdominal area.
The danger?
It's well established that abdominal fat is an independent risk
factor for diabetes, which, of course, increases risk for many health
problems.
The three-year study, published in the American Journal of Clinical
Nutrition, tracked eating habits of 459 healthy people, both
male and female, with an average age of 60 [5]. The purpose of the
study: To see how the types of foods participants habitually ate
impacted their waist circumference.
After analyzing the food-intake habits of the participants, the
researchers determined that there were five basic dietary patterns.
Members of the white-bread group (16% of daily calories from white
flour) ate five times more refined flour products than members of
the healthy group did... and gained three times what the healthy
group did in the abdomen, expanding about one-half inch in the waist
per year of the study.
According to the study's lead author, Dr. P. Kirsten Newby, the
dominant feature of the study results was not that the healthy group
ate a lot of whole-grain products. In fact, these accounted for
just 1% of their total calorie intake. Rather, she says, it was
that they ate such a limited amount of white bread and flour products.
Dr. Newby and her colleagues can only speculate about the reason
white-flour consumption results in fat deposits in the abdomen,
but what is certain is that white and refined flours have again
been shown to be nonhealthful.
Grains come in many shapes and sizes, from large kernels of popcorn
to small quinoa seeds. Grains, also called cereals, are the widely
varied seeds of grasses, which are cultivated for food.
Grains are the seeds of plants. When whole, they include the bran,
germ and endosperm — all of which contain beneficial nutrients.
• Bran. Forming the outer layer of the seed, the
bran is a rich source of niacin, thiamin, riboflavin, magnesium,
phosphorus, iron and zinc. The bran also contains the majority
of the seed's fiber.
• Germ. The part from which a new plant sprouts,
the germ is a concentrated source of niacin, thiamin, riboflavin,
vitamin E, magnesium, phosphorus, iron and zinc. The germ also
contains protein and some fat.
• Endosperm. Also called the kernel, the endosperm
makes up the bulk of the seed. It contains most of the grain's
protein and carbohydrates and has small amounts of vitamins and
minerals.
Refined grains, such as white rice or white flour, have both the
bran and germ removed from the grain. Although vitamins and minerals
are added back into refined grains after the milling process, they
still don't have as many nutrients as whole grains, and they don't
provide the fiber.
Identifying whole grain products is not always that simple. It's
easy to be deceived by breads labeled "nine-grain," "rye
bread" or "made with whole grain."
Whole grain products should list a whole grain ingredient, such
as "whole wheat," "whole rye," "whole-oats"
as the first ingredient on the label.
They contain magnesium, vitamin E and some B vitamins, and are
an excellent source of fiber, something Americans under consume.
The good news is that there are a number of delicious and nutritious
non-wheat grains available.
Gluten, the grain protein that gives dough its elasticity, frequently
is the culprit behind wheat sensitivity. Many people may be wheat-gluten
sensitive but not know it.
Dr. Judith Mabel, RD, PhD points out that hluten can cause digestive
problems, such as constipation, and endocrine problems.
To underscore her point, she reminds people that when children
make paste for gluing, it is composed of flour and water, which
is not too different from the recipe for pasta and other wheat products.
In addition to wheat, gluten is present in rye, barley, spelt, kamut,
farina, triticale and, in the Western world, couscous. (In Africa,
couscous is made with millet.)
Related Articles
References
1. Liu S, Willett WC, Manson JE, Hu FB, Rosner B, Colditz G.
(2003).
Relation between changes in intakes of dietary fiber and grain products
and changes in weight and development of obesity among middle-aged
women. American
Journal of Clinical Nutrition, 78, 920-927
2. Lopez-Ridaura R, Willett WC, Rimm EB, Liu S, Stampfer MJ, Manson
JE, Hu FB. (2004). Magnesium intake and risk of type 2 diabetes
in men and women. Diabetes
Care, 27, 134-140
3. McKeown NM, Meigs JB, Liu S, Saltzman E, Wilson PW, Jacques PF.
(2004). Carbohydrate nutrition, insulin resistance, and the prevalence
of the metabolic syndrome in the Framingham Offspring Cohort. Diabetes
Care, 27, 538-546
4. Song Y, Manson JE, Buring JE, Liu S. (2004). Dietary magnesium
intake in relation to plasma insulin levels and risk of type 2 diabetes
in women. Diabetes
Care, 27, 59-65
5. Newby PK, Muller D, Hallfrisch J, Andres R, Tucker KL. (2004).
Food patterns measured by factor analysis and anthropometric changes
in adults. American
Journal of Clinical Nutrition, 80, 504-513
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