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Go Nuts!
By
Nancy Emerson
Lombardo |
 All
nuts and seeds provide antioxidants, fiber, and healthy
types of fat that help regulate blood sugar and lower
cholesterol levels. A daily handful of almonds or hazelnuts
and certain seeds, help provide Vitamin E - an essential
brain cell protector. Recommended portions size is 1.5-3 oz
per day as calories are relatively high (150-200 calories/
oz for most nuts). Clinical research suggests however that
people adding nuts to their usual diet do not gain weight,
possibly because nuts are so filling people naturally cut
back on other foods and perhaps nuts also assist metabolism.
Since we are all different, observe results for yourself. To
limit sodium intake choose unsalted versions if possible;
nuts themselves usually contain very little sodium.
Nuts and seeds are stars among brain healthy foods and
eating a daily portion of a variety will help you reduce LDL
cholesterol, blood sugar, oxidative stress and inflammation,
all risk factors for Alzheimer’s disease and some other
brain diseases. Nuts and seeds are whole foods rich in plant
proteins, unsaturated fatty acids, dietary fiber, minerals,
vitamins and other antioxidants, as well as phytosterols,
consumed by humans throughout human history, but neglected
in more recent decades. Nuts and seeds are increasingly
recommended to help people prevent or treat heart disease,
diabetes and other chronic diseases that are themselves risk
factors for Alzheimer’s and other brain diseases.
Only almonds have been looked at specifically for impact on
Alzheimer’s-related pathology, using AD transgenic mice.
Both studies (by the same researcher, Abha Chauhan at New
York State Institute for Basic Research in Developmental
Disabilities) found significant positive effects on both
lowering the problem A-beta protein and improving cognition
in AD transgenic mice. Yet almond’s prominent feature is
vitamin E and high mono-unsaturated fatty acid content and
walnut’s is their high Omega-3 content. The most recent
study found that a dietary addition of the equivalent for
humans of just 1 to 1.5 oz of walnuts in the mice (who were
previously impaired) diet improved learning, memory,
emotional regulation and motor coordination.
Perhaps Alzheimer’s researchers will next look at pistachios
featured recently by Tufts Nutrition Letter: “Penn State
researchers report that pistachios not only lower “bad”
cholesterol but also pack a potent antioxidant punch.
Pistachios contain higher amounts of antioxidants, including
beta-carotene, gamma-tocopherol and lutien than most other
nuts, which may help pistachios combat inflammation in the
body.” Gamma-tocopherol has been reported by AD researchers
(Martha Morris and others) to be especially important for
the brain. A 1-oz serving of pistachios, with 160 calories,
also offers an excellent source of vitamin B6, copper and
magnesium; and are a good source of fiber, thiamin and
phosphorus.
Heart Health And Blood Sugar
All nuts and seeds also promote brain health through
their positive impact on heart health and blood sugar
regulation. Nuts and seeds are an excellent source of
plant protein and fiber. Fiber provides a feeling of satiety
and helps decrease harmful LDL cholesterol by binding it in
the intestinal tract and reducing its absorption. Plant
sterols are another prominent group of compounds found in
nuts and seeds. Plant sterols are believed to lower serum
cholesterol levels thereby reducing the risk of coronary
heart disease.
Nuts and seeds are also a great source of healthy mono and
poly-unsaturated fats. Monounsaturated fats help raise the
“good” HDL cholesterol without contributing to a rise in the
“bad” LDL cholesterol levels. Researchers have observed a
decrease in cardiovascular disease in persons who include
mono- and poly-unsaturated fatty acids in their diets. In
addition, dietary intake of unsaturated fats has been shown
to lower blood pressure, prevent blood clot formation,
protect against irregular heart rhythm and reduce
inflammation.
A recent meta-analysis of 25 previous studies confirms this
finding (see Joan Sabate, MD, Dr. PH lead author’s article
in Journal of Nutrition, June, 2010. abstract at
jn.nutrition.org/cgl/content/abstract/140/ 6/1093?etoc).
Most of the reviewed studies focused on almonds and walnuts;
the average amount consumed by people in the intervention
groups was 2.4 oz. The length of the studies ranged from
three to eight weeks.
A Tufts Health and Nutrition Letter report states, “Compared
to control groups, participants adding nuts to their diets
saw an average 5.1% decrease in total cholesterol, 7.4%
decrease in “bad” LDL cholesterol, and 8.3% improvement in
ratio of LDL to “good” HDL. Those with high triglyceride
levels saw a 10.2% decline. Different types of nuts had
similar effects.”
We agree with Dr. Sabate’s statement in Archives of Internal
Medicine that “Dietary interventions to lower blood
cholesterol concentrations and to modify blood lipoprotein
levels are the cornerstone of prevention and treatment plans
for coronary heart disease,” and suggest they are also the
cornerstone of prevention and treatment plans for many brain
diseases.
The Omega’s
Polyunsaturated fatty acids include vegetable type
Omega-3s (ALA) and Omega-6 fatty acids. Omega 3’s and 6’s
are essential fatty acids which cannot be produced in the
body so we must eat them as part of our diet. The body uses
essential fatty acids to make eicosanoids, a group of
compounds that participate in the immune response to injury
and infection.
Nuts and seeds are also high in antioxidants, most notably
Vitamin E. Almonds and hazelnuts are known to be especially
high in vitamin E, and Brazil nuts, peanuts and pine nuts
are “good” sources.
Antioxidants play a key role in reducing oxidative stress
caused by the environment as well as chemical reactions in
the body as part of metabolism. Eating more antioxidants may
reduce cancer risks by protecting cell DNA from damage.
Other beneficial components found in nuts and seeds include
the B-vitamins (including foliate, niacin and thiamine) and
minerals such as copper, magnesium, manganese, phosphorus,
potassium, and sulfur.
The B vitamins are critical to maintaining healthy brain
function, both for mood and cognition. B vitamins are also
important as coenzymes in metabolism and for helping to
lower blood homocysteine levels. Research shows an
association between elevated blood homocysteine and a higher
risk of coronary heart disease, so keeping homocysteine
levels low is recommended.
Monounsaturated fatty acids are found in many nuts and seeds
with highest amounts in macadamia nuts, almonds, cashews,
pecans, hazelnuts, pistachios, and peanuts. Sesame seeds
also contain a high amount of monounsaturated fats.
Nuts highest in Monounsaturated Fatty Acids (MUFA) include
Macadamia (79% of total fat is MUFA), Almonds (65%), Pecans
(62%), Cashews (59%), Peanuts (50%), whereas Walnuts it is
only 23%. Walnuts are prized for their high Omega-3 and
Omega 6 content.
Omega-3 polyunsaturated fatty acids are found in higher
quantities only in walnuts and some pine nuts and also in
flax seed and flax seed and canola oils. The Omega- 6 fatty
acids are particularly high in walnuts, with some found in
most nuts, and high quantities also are found in pumpkin (pepita)
seeds and sunflower seeds.
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About The Author
Nancy Emerson Lombardo, Ph.D., is a nationally recognized
researcher and lecturer on brain healthy lifestyles. She is
President of HealthCare Insights, LLC and developer of the
Memory Preservation Nutrition® program of brain healthy
foods, the Brain Health and Wellness Center® as well as
Adjunct Professor of Neurology at Boston University School
of Medicine. She is available for consultation to
individuals and companies, including group meal services.
She can be reached by email at nemerson@healthcareinsights.net,
or by telephone at (978) 621-1926.
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