Could an avocado a day keep cholesterol at bay?
January 19, 2015
By Dr. Mercola
January 19, 2015
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:
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.
- 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
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:
The results, reported by the NPR,9 “surprised” the researchers:
- 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
“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:Source:
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.
- 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
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.
Click below to expand the
infographic.
http://articles.mercola.com/sites/articles/archive/2015/01/19/avocado-helps-lower-bad-cholesterol.aspx?e_cid=20150119Z1_DNL_NonBuyer_art_1&utm_source=dnl&utm_medium=email&utm_content=art1&utm_campaign=20150119Z1-NonBuyer&et_cid=DM65508&et_rid=810468901