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Diet and Weight Loss Study
Unhealthy Girl Scout Cookies
Vitamin D and Colon Cancer
Maintaining Muscle with Aging
Selenium and Cognitive Function
Chronic Lead Exposure and Cognition
A new research report in the Journal of the American Medical
Association suggests that the high-protein, high-fat Atkins-type
diet does better for weight loss over 12 months than the
three other diets studied: the Zone, Ornish, and LEARN (U.S.
Guidelines) diets. (Gardner CD, et al., Comparison of the
Atkins, Zone, Ornish, and LEARN Diets for Change in Weight
and Related Risk Factors Among Overweight Premenopausal Women.
The A TO Z Weight Loss Study: A Randomized Trial JAMA. 2007
March 7;297(9):969-977.
The 311 non-diabetic, pre-menopausal female subjects were
all overweight or obese (body mass index, or BMI, of 27-40)
at both the start and the end of the study.
However, the differences in weight loss between the Atkins
diet and the Ornish or LEARN diets were not statistically
significant, and by the end of the study virtually none of
the subjects were following any of the diets closely, making
it hard to draw any firm conclusions about the value of the
diets for weight loss.
This did not, however, stop the press from drawing such
conclusions, at least in their headlines. “Atkins beats
other diet plans…” said the AP; “Diet
study tips scale in favor of Atkins” said Reuters (and
went on to say that the Atkins subjects lost twice as much
weight as the others, even though the difference was not
statistically significant!); “Atkins diet wins for
losing” said the LA Times.
What is lost in all the hype is the real information that
people need. All of the subjects were very overweight or
obese. When the study started, their average weight was 190
pounds, so a weight loss of 10 pounds is barely meaningful
(unless it is a harbinger of continued weight loss, which
it apparently was not, as they had already fallen off the
diets and started to gain their weight back). Between 6 months
(the peak weight loss in the Atkins group) and the end of
the study at 12 months, the subjects had already gained back
20 percent of their weight.
The real guidance that people need is what dietary practices
will make them healthy in the long term, not simply help
them with weight reduction for a few months, and for this
the data is fairly clear. It is also common sense and not
likely to generate headlines.
Reducing refined carbohydrates (particularly sugar, corn
syrup, and white flour) is important in any diet, but fresh,
whole foods that contain complex carbohydrates (from whole
grains, vegetables, beans, and fruits) are important sources
of nutrients, phytochemicals, and fiber.
These foods are associated with a reduction of the risk
of heart disease, cancer, hypertension, strokes, and diabetes,
the most significant causes of premature death. Diets that
emphasize fats and animal proteins at the expense of healthier
whole, natural, plant-based foods preclude adequate intake
of these protective nutrients.
For ideas on how to include healthier complex carbohydrates
and whole, natural foods in the diet, check out prior newsletters
and the recipes that you will find in them. At least avoid
being misled by fad diets that focus only on weight loss
rather than overall long-term health.
A recent news report noted that Girl Scout’s Cookies
are now being produced with “little to no” trans
fats, the byproduct hydrogenation, found in partially hydrogenated
vegetable oils, that increase the risks for heart disease
and probably cancer, and immune disorders. (Girl Scouts cut
trans fats from cookies. Associated Press, February 23, 2007.)
Trans fats occur naturally in only minuscule amounts in some
foods (such as meat and dairy products), and they raise LDL
cholesterol while lowering levels of the good HDL cholesterol.
However, although the Girl Scout cookies may be labeled
as containing no trans fats, regulations still allow them
to contain some trans fats! A small serving (most people
probably eat more than one serving at a time) may contain
half a gram of trans fats, so someone might accumulate a
significant trans fat intake over a day.
In any case, while Girl Scouts use the cookies as a significant
money maker, they are not in any way healthy. Aside from
any residual hydrogenated oils, they also contain primarily
saturated fat, white flour, and plenty of refined sugar,
as well as artificial flavors, colors, and preservatives.
In fact, one flavor contains over two teaspoons of sugar
per serving. In others, sugar is the first ingredient.
Considering the massive and growing problem with obesity
among children, including girls of Girl Scout age, perhaps
the Girl Scouts could send a healthier message. Their spokesperson
says they “know they are not selling broccoli” and
that their cookies are not meant to be a major part of the
diet. This does not diminish the negative effects of these
harmful snacks. Maybe they should be promoting broccoli (and
other vegetables and fruits) and find other ways to fund
activities.
A new study shows that higher intakes of vitamin D can prevent
colorectal cancer (Gorham ED, et al., Optimal vitamin D status
for colorectal cancer prevention a quantitative meta analysis.
Am J Prev Med. 2007 Mar;32(3):210-6). This study was a meta-analysis
(study of studies), pooling data from five different published
reports. Researchers found that among all the subjects, the
highest serum levels of vitamin D were associated with a
50 percent reduction in the risk of colorectal cancer. They
estimated that the highest serum levels were correlated with
a vitamin D intake of 1000 to 2000 IU per day. This is higher
than most people get from the sun and food sources, especially
in elderly people (who do not manufacture vitamin D efficiently),
people in northern latitudes who have less sun exposure,
or those who carefully avoid all sun exposure. (Of course,
excessive sun exposure is still associated with an increased
risk of skin cancer.)
While some sun exposure, but not excessive amounts, is a
good idea, it is safer and as effective to take supplements
of natural vitamin D. Natural vitamin D is listed as D3 (or
cholecalciferol) on labels, as opposed to the synthetic D2
(ergocalciferol) that is often added to foods or commercial
dietary supplements. I have noticed that some soy milk has
recently been produced with natural vitamin D, rather than
the synthetic form that I used to see on the labels.
Elderly people tend to lose muscle strength and muscle mass,
but it is possible for the elderly to build muscle with exercise.
A study of 20 women and 4 men showed that a training program
of resistance exercise for 12 weeks led to a gain of 6.4
pounds of new muscle and a loss of 8.8 pounds of fat (Wieser
M, Haber P, The effects of systematic resistance training
in the elderly. Int J Sports Med. 2007 Jan;28(1):59-65).
The exercises were as effective whether they were done twice
or three times a week, as long as the total number of repetitions
was the same. Average muscle strength increased 15 percent,
while maximum strength went up between 26 and 38 percent,
depending on the muscle group tested. Muscle oxygen use went
up 12 percent by the end of the study. This once again shows
that it is never too late to start a health program. Of course,
the earlier you start a health program the more likely you
are to achieve the long-term benefits, rather than getting
weak and ill and having to play catch-up.
Selenium is an important trace mineral nutrient. With age,
plasma selenium levels frequently decline, and at the same
time aging is associated with worsening brain function. A
large study in France shows that loss of cognitive function
is worse in those people in whom selenium levels decline
the most. Researchers followed 1389 subjects for 9 years
plus follow-up evaluations (Akbaraly NT, et al., Plasma selenium
over time and cognitive decline in the elderly. Epidemiology.
2007 Jan;18(1):52-8). Those whose selenium level in the plasma
declined the most had the worst cognitive decline, after
accounting for other risk factors. As selenium is an anti-oxidant
cofactor (essential for the activity of the antioxidant enzyme
glutathione peroxidase), this is one further piece of evidence
that oxidative damage is one contributor to loss of brain
function. Selenium is a safe supplement, and is often low
in the diet.
An earlier report by this same research group on the same
subjects showed that overall mortality rates were higher
in subjects with low selenium levels compared to those with
higher serum selenium. (Akbaraly NT, et al., Selenium and
mortality in the elderly: results from the EVA study. Clin
Chem. 2005 Nov;51(11):2117-23.) Selenium is frequently in
multi-vitamin/mineral formulas, but it is important to make
sure to get adequate amounts. Many areas of the country have
low soil selenium, leading to low dietary intake, in spite
of the fact that many of our foods come from a variety of
geographic sources.
Total lifetime lead exposure is related to cognitive function
in the elderly. A study of blood and bone lead levels showed
that as lead concentration in bone went up, cognitive function
declined, as measured by vocabulary studies, reaction times,
and pattern comparison tests. The relationship did not hold
for blood lead alone, indicating that it is lifetime exposure
to lead that leads to the problem. (Weisskopf MG, et al.,
Cumulative lead exposure and cognitive performance among
elderly men. Epidemiology. 2007 Jan;18(1):59-66.) Long-term
exposure results in lead accumulation in the bones (as well
as liver and neurological tissues) and, as are other heavy
metals, is associated with acute and chronic health problems,
including heart disease and cancer. Treatment with chelation
therapy, such as intravenous treatment with EDTA for vascular
disease or oral treatment with DMSA for toxic metal excess,
is safe and effective..
drjanson@drjanson.com
Practice phone: 603-878-2256
180 Massachusetts Ave., Suite 303
Arlington, MA 02474
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