Herbs & Supplements

Should I take it?

Avocado is a familiar part of the diet in Central America and South America, where the round or pear-shaped fruits are eaten raw, used for a spread, or made into a dip commonly known as guacamole. Avocados are native to the Americas with three main types originating in Guatemala, Mexico, and the West Indies. The fruits of the Guatemalan variety take 12 months to 18 months to mature. They have dark green or black rinds that are very bumpy and thicker than other varieties. Avocados from Mexico are smaller, they ripen in less time--typically 6 months to 8 months--and they have smoother, thinner skins. West Indian avocados have smooth, lighter green skins. The largest variety, each ripe West Indian avocado can weigh up to three pounds. When they are ripe, all varieties of avocado have a wide layer of soft, oily, yellow-green pulp surrounding a single large seed. As much as one-quarter of the fruit's weight is in the seed, and up to another one-third is composed of monounsaturated oil. Because avocado oil spoils quickly, however, it should be kept refrigerated for no longer than about 6 months.

Avocado trees are large, wide, rapidly-growing evergreens that can grow as tall as 80 feet. In commercial orchards, the trees are pruned to keep their height manageable for harvesting fruits. The wood is easily broken and the roots are relatively shallow, so the trees do not survive well in areas with a lot of wind. Although they need high humidity, avocados also cannot stand swampy locations. And most do not tolerate freezing temperatures for very long. Therefore, they grow best at higher elevations in subtropical areas with lots of sunlight.

In the U.S., avocados are cultivated commercially in California, Florida, and Hawaii. Although wild avocado trees take much longer to produce fruits that can be eaten, cultivated trees begin to bear fruits after about 3 years. Avocado trees usually reach full production at 5 years to 8 years and remain productive for a century or longer. Small greenish-white flowers that bloom in long clusters are followed by groups of two or three avocado fruits. Avocados reach full size on the tree, then they are picked by hand and allowed to ripen. Depending on conditions, an average size tree produces 100 to 400 avocados per year.

Compared to other fruits and vegetables, avocado fruits are relatively high in protein and fiber. They also contain significant amounts of iron, lutein, potassium, vitamin C, and vitamin E. In fact, avocados have higher contents of lutein and potassium than any other fruit and their high fat content (5 grams to 10 grams per ounce) actually may increase the absorption of fat-soluble nutrients, such as vitamin E and lutein. At 50 calories to 60 calories per ounce, though, avocados are quite high in calories. Avocado oil is used for cooking and in skin care and hair care products. A liquid obtained from the seeds has been used as ink.

Dosage and Administration

For treating osteoarthritis (OA), a combination of one-third avocado unsaponifiables and two-thirds soybean unsaponifiables has been used. In most studies, individuals took either 300 mg or 600 mg of the combination (known as ASU) per day. Both doses appeared to relieve symptoms of OA, but the higher dose did not provide more effects or cause more side effects than the lower dose.

Summary

Avocados, avocado oil, and a combination of avocado oil and soy oil known as ASU may help to lower cholesterol. They may also provide some relief for osteoarthritis symptoms.

Risks

Many parts of the avocado tree may contain harmful amounts of persin, a chemical that can destroy breast tissue and may damage the heart. Ingesting avocado bark, leaves, roots, or any part of the avocado other than its fruits is strongly discouraged.

Side Effects

Individuals who are allergic to latex or to other tropical fruits, such as bananas or kiwi, may also be allergic to avocado. Large doses of avocado or avocado oil may have mild laxative effects.

Interactions

Avocado may decrease the effects of blood-thinning drugs such as warfarin and aspirin. The oil in it may interfere with the absorption of drugs or some nutrients from food, but fat-soluble nutrients may be absorbed better when taken with an oily food such as avocado.

Last Revised September 25, 2007