Avocados Health Benefits
Avocados contains the good monounsaturated fats. More than half its calories are these types of fats.
The good fats in avocados has the effect of improving your cholesterol profile by lowering the bad LDLs and raising the good HDLs.
EatingWell.com says "The monounsaturated fats in avocados have been found to lower “bad” LDLs and raise “good” HDLs, especially in people with mildly elevated cholesterol."
Avocado also contains heart-healthy oleic acid and omega-3 fatty acids (in form of alpha-linolenic acid).
Because what is good for the arteries is also good for the brain, WebMD says that "Avocados are almost as good as blueberries in promoting brain health."
Avocado does have a bit of saturated fat. But it is the "not-so-bad" kind of saturated fat. It is not as bad as the saturated fat from deep fried foods and hydrogenated vegetable oils.
Why You Should Eat Good Fats
Rule #5 of the Amen Solution is to "Focus Your Diet on Healthy Fats". In the book "The Amen Solution: The Brain Healthy Way to Lose Weight and Keep It Off" says ...
"Focus your diet on healthy fats, especially those that contain omega-3 fatty acids, found in foods like salmon, avocados, walnuts, and green leafy vegetables." [page 22]
The book "You: The Owner's Manual" by Dr. Michael Roizen and Dr. Mehmet Oz says that one quarter of a person's calories should come from good fats.
In the below video, Jeff Primack says to eat at least one avocado a day...
Avocado Anti-inflammatory and anti-oxidant properties
The antioxidant properties comes from vitamin C, vitamin E, glutathione, and beta-carotene contained in avocados. In particular, glutathione is also an detoxifier and plays an important role in controlling inflammation and in immune functions.
Avocado has anti-inflammatory properties through carotenoid antioxidants and alpha-linolenic acid and others. Vitamin K in avocados also reduces inflammation.
One cup of avocado has 36% DV (daily value) of vitamin K and 19% DV of vitamin C. It also has folate, potassium, magnesium, and vitamin B6.
It is always a good idea to keep Dr. Andrew Weil's Anti-Inflammatory Pyramid in mind (see picture in previous link). At the base of the pyramid, it shows that we should eat fruits and vegetables the most. Then comes whole grains, pasta, and bean. And next comes the healthy fats, which he shows as being extra virgin olive oil, nuts, seeds, and of course avocados.
So you see, avocados fits in two different parts of the anti-inflammatory pyramid. It fits in the base as a fruit (avocados are fruits because it has a big seed in the center; although many people think of it as a vegetable). And it fits in the pyramid under the "healthy fats".
Dr. Nicholas Perricone wrote the article "An Avocado a Day Keeps the Bad Fats Away" which says that avocados are "rich in anti-inflammatory, anti-aging, disease-fighting phytochemicals". Being creamy and soft, they can be substituted instead of using saturated fats. Instead of mayonnaise on your sandwich, put avocados instead. Instead of thick dressing on the salad, use sliced avocados. Instead of sour cream in your burrito, put guacamole (an avocado-based dip) instead. Avocado has no cholesterol.
Other Avocado Benefits
Like kale, avocado has lutein and zeaxanthin for good eye-health.
When eating alongside with avocado, certain nutrients are better absorbed by the body. This is because of the fat content in avocado increases carotenoid absorption.
How to Ripen Avocado
A ripe avocado should be firm, but will give slightly when pressed softly. Those that are too soft are overly ripe. Hard avocados that do not give when pressed are not ripe. However they can ripen on its own while sitting at room temperature.
For many fruits and vegetables, the ones that are picked at optimum ripeness contains more vitamins and nutrients than ones picked unripe. This is because the fruit is able to develop its full spectrum of nutrients while on the plant. 
However, for avocados this is not true. This is because avocado do not ripen on the tree, they only become soft after being picked. So hard avocados on store shelves that costs less are not inferior fruits, but rather better value fruits.
To speed up the ripening process, place hard unripe avocados in a paper bag with an apple or a banana. This is because fruits such as apple or banana will give off the plant hormone ethylene which triggers the ripening process. The bag is used to trap this gaseous hormone with the avocado.
Omega-6 and Omega-3 Ratio of Avocados
As with certain things, more is not better. One downside of avocados is its unfavorable omega-6 to omega-3 ratio, one avocado contains 3.9 grams of inflammatory omega-6 and only 0.3 grams of omega-3 [reference]. So if one is trying to reduce consumption of omega-6, limit the number of avocados.
-  10 Health Benefits of Avocados
Here are ten health benefits of avocado and ten reasons that an avocado a day might just keep the doctor away.
-  WHFoods: Best Way to Ripen Avocados
-  New Research Shows Avocados Act as Nutrient Booster - Everything Science
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-  How to Store Avocados :: How to Freeze Avocados, How to Prevent Avocados from Turning Brown
Find everything you need to know on how to freeze avocados, how to freeze guacamole, how to store cut avocados, how to store guacamole and more. Learn why avocados brown and how to prevent browning of avocados. Find tips on how to store avocados afte
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