How Avocado Can Help Improve Your
Cholesterol, Heart, and Brain Health
January 19, 2015
Story
at-a-glance
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Avocados are an excellent source of heart-healthy
monounsaturated fat that is easily burned for
energy, while being low in fructose. They also
provide close to 20 essential nutrients, including
high levels of potassium
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Research shows that avocados can help improve lipid
profiles, and can lower LDL cholesterol twice as
effectively as a diet of equal fat ratio without the
inclusion of avocado
-
Healthy fats, both from avocado and other sources,
are also vital for optimal brain function, and for
the prevention of degenerative brain disorders like
Alzheimer’s
By Dr. Mercola
Avocados are an excellent source of heart-healthy monounsaturated
fat that is easily burned for energy, while being low in fructose.
Not surprisingly, improved weight management1,2
is one of the health benefits of avocado consumption, and its
high-fat, low-sugar content is likely a key factor contributing to
this effect.
Research3
has also found that avocados are helpful for regulating your blood
sugar levels. This is an important benefit for most people,
considering that one in four American are either
diabetic or pre-diabetic.
According to the California Avocado Commission, a medium Hass
avocado contains about 22.5 grams of fat, two-thirds of which is
monounsaturated. They also provide close to 20 essential
health-boosting nutrients, including:
- Fiber
- Vitamin E
- B-vitamins
- Folic acid
- Potassium (more than twice the amount found in a banana),
which can help balance your vitally important
potassium to sodium ratio
Due to its beneficial raw fat content, avocado enables your body
to more efficiently absorb fat-soluble nutrients (such as alpha- and
beta-carotene and lutein) in other foods eaten in conjunction.
One 2005 study4
found that adding avocado to salad allowed the volunteers to absorb
three to five times more carotenoids antioxidant molecules,
which help protect your body against free radical damage.
An Avocado a Day May Help Lower Bad Cholesterol
Previous research has suggested that avocados might help improve
lipid profiles, both in healthy individuals and in those with mild
hypercholesterolemia (elevated cholesterol levels).
In one such study,5
healthy individuals saw a 16 percent decrease of serum total
cholesterol level following a one-week long diet high in
monounsaturated fat from avocados.
In those with elevated cholesterol levels, the avocado diet
resulted in a 17 percent decrease of serum total cholesterol, and a
22 percent decrease of both LDL-cholesterol and triglycerides, along
with an 11 percent increase of the so-called “good” HDL cholesterol.
More recently, researchers at Pennsylvania State University
tested three different cholesterol-reducing diets, to assess and
compare their effectiveness.6,7,8
Forty-five overweight participants were enrolled in the study, and
were assigned to follow one of the tree diets:
- Low-fat diet, where saturated fats were substituted for more
carbohydrates, including plenty of fruit and whole grains
- Moderate-fat diet (without avocado), where saturated fats
were substituted with monounsaturated fats in the form of canola
and sunflower oil. About 34 percent of daily calories came from
fat, but aside from that, it was very similar to the low-fat
diet, which included poultry and low amounts of red meat
- Moderate-fat diet with avocado. Aside from including one
whole Hass avocado per day, this diet was identical to the other
moderate-fat diet, and the overall fat ratio was the same
The results, reported by the NPR,9
“surprised” the researchers:
“At the end of the study, the researchers found that the
avocado diet led to significant reductions in LDL cholesterol,
compared with the other two diets.
To put the difference in perspective, the avocado diet
decreased LDL cholesterol about 14 milligrams per deciliter of
blood. Compare that with a decrease of about 7 mg/dL for the
low-fat diet, and about a 8 mg/dl drop from the moderate-fat
diet.
"I was surprised to see the added benefit [of the
avocado]," Penny Kris-Etherton, a nutrition scientist at Penn
State and the lead author of the study, tells us." It's
something in the avocado" other than just the fat composition,
she says.”
All Fats Are Not Created Equal
It’s worth noting that
canola and other vegetable oils (used in the moderate-fat diets
in the featured study) are typically hydrogenated, which means they
contain
trans fats, and trans fats wreak havoc on your heart and
cardiovascular health. So I for one am not surprised at the
results of this study.
Previous research10
has actually shown that replacing saturated fats with carbohydrates
and omega-6 polyunsaturated fats (found in soybean, corn, and
safflower oil) leads to increased
small, high-density LDL particles, increased oxidized LDL, and
reduced HDL.
Research has confirmed that large LDL particles do not
contribute to heart disease. The small, dense LDL particles,
however, do contribute to the build-up of plaque in your arteries,
and trans fat increases small, dense LDL. (Saturated fat, on the
other hand, increases large, fluffy—and benign—LDL.)
Research has also shown that small, dense LDL particles are
increased by eating refined sugar and carbohydrates, such
as bread, pasta, and most processed foods. Together, trans fats and
refined carbs do far more harm than saturated fat ever possibly
could. One tool designed to help you eliminate trans fats are the
Naturally Savvy Get
Healthy Challenges that I helped create.
A Note on the DASH Diet...
On a brief side note: In the CBS video above, they also make
mention of the DASH diet, which has been found to lower blood
pressure by as much as five points, rivaling the effects of blood
pressure lowering medications.
The DASH diet is quite similar to the Mediterranean diet,
promoting the consumption of vegetables, fruits, lean protein, whole
grains, and low-fat dairy, and recommends avoiding sugars, red meat,
and salt.
Many believe that the low-sodium
is responsible for its success. However, there’s compelling evidence
suggesting that the real reasons it works so well for both
hypertension and weight loss is because it increases potassium and
restricts your intake of fructose—as does the Mediterranean
diet.
Fructose is actually a far more important factor than salt when
it comes to hypertension. The connecting link between fructose
consumption and hypertension lies in the uric acid produced.
Uric acid is a byproduct of fructose metabolism, and
increased uric acid levels drive up your blood pressure.
Now, when you reduce sugar in your diet (from sources such as
added sugars, processed fructose, grains of all kinds, and processed
foods), you need to increase the amount of healthy fat. And avocado
is an excellent choice to bolster your fat consumption and
overall nutrition.
I have been consuming an avocado daily for the last several
years. On most days, I will add a whole avocado to my salad, which I
eat for lunch. This increases my healthy fat and calorie intake
without seriously increasing my
protein or carbohydrate intake. You can also add about ¼ to 1/3
of an avocado as a healthy banana substitute when making smoothies
or your protein shake.
Avocado Benefits Your Heart and Brain
Besides its beneficial influence on your cholesterol, avocados
have also been found to provide other heart-healthy benefits. For
example, one interesting 2012 study11
found that eating one-half of a fresh medium Hass avocado with a
hamburger significantly inhibited the production of the inflammatory
compound Interleukin-6 (IL-6), compared to eating a burger without
fresh avocado.
Also, just like avocado does not raise your blood sugar levels,
fresh avocado did not increase triglyceride levels beyond what was
observed when eating the burger alone, despite the avocado supplying
extra fat and calories. According to lead author David Heber, MD,
PhD, the findings offer “promising clues” about avocado’s ability to
benefit vascular function and heart health. Healthy fats are also
vital for optimal brain function, and for the prevention of
degenerative brain disorders like Alzheimer’s. As noted in a recent
issue of Scientific American:12
“The brain thrives on a fat-rich, low carbohydrate diet,
which unfortunately is relatively uncommon in human populations
today,” reports
David Perlmutter, author of Grain Brain. “Mayo Clinic
researchers showed that individuals favoring carbohydrates in
their diets had a remarkable 89 percent increased risk for
developing dementia as contrasted to those whose diets contained
the most fat.
Having the highest levels of fat consumption was actually
found to be associated with an incredible 44 percent reduction
in risk for developing dementia.” ...‘Good’ fats include
monounsaturated fats, found abundantly in olive oil, peanut oil,
hazelnuts, avocados and pumpkin seeds, and polyunsaturated fats
(omega 3 and omega 6), which are found in flaxseed oil, chia
seeds, marine algae oil and walnuts.”
To Maximize Benefits, Peel Your Avocado the Right Way
Interestingly, the manner in which you de-skin your avocado can
affect how much of its valuable phytonutrients you get out of it.
UCLA research has shown that the greatest concentration of
beneficial carotenoids, for example, is located in the dark green
fruit closest to the inside of the peel. In 2010, the California
Avocado Commission issued guidelines for getting the most out of
your avocado by peeling it the right way.13
To preserve the area with the greatest concentration of
antioxidants, you’re best off peeling the avocado with your hands,
as you would a banana:
- First, cut the avocado length-wise, around the seed
- Holding each half, twist them in the opposite directions to
separate them from the seed
- Remove the seed
- Cut each half, lengthwise
- Next, using your thumb and index finger, simply peel the
skin off each piece
How to Get More Avocado into Your Diet
While avocado is commonly eaten raw, on salad or alone, there are
many other ways to include avocado in your diet. Its creamy, mild
flavor tends to go well with many foods, making it a refreshing and
nutritious addition to various recipes. For example, you can use
avocado:
- As a fat replacement in baking. Simply replace the fat
called for (such as oil, butter, or shortening) with an equal
amount of avocado
- As a first food for babies, in lieu of processed baby food
- In soups. For examples, see Lucy Lock’s
Chilled Mediterranean Soup, or her
Raw Creamy Carrot Soup
- As a banana substitute in smoothies or your protein shake
The California Avocado Commission’s website14
contains hundreds of unique recipes that include avocado. All in
all, avocado may be one of the most beneficial superfoods out there,
and may be particularly valuable if you’re struggling with insulin
and leptin resistance, diabetes, or any other risk factors for heart
disease. Last but not least, avocados are also one of the safest
fruits you can buy conventionally-grown, as their thick skin
protects the inner fruit from pesticides.
On top of that, avocados have been rated as one of the safest
commercial crops in terms of pesticide application,15
so there’s no real need to spend extra money on organic avocados.
I’ve had my own team test avocados from a variety of growers in
different countries, sold in several major grocery stores, and they
all tested free and clear of harmful chemicals. For more
fun and interesting avocado facts, check out the following
infographic.
Copyright 1997- 2015 Dr. Joseph Mercola. All Rights Reserved.
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