Botanical Name: Persea americana.
The plant Genus “Persea” contains about 150 species.
Other Common Names: Avocado pear, alligator pear, midshipman’s butter, vegetable marrow, avocatier (French), aguacate (Spanish), avokado (Swedish).
Habitat: The avocado tree belongs to the Lauraceae family and it is originally native to Mexico and South and Central America, where it grows in the wild. Because of its tasteful and nutritious fruit (botanically a large berry), it has probably been cultivated in these areas since ancient times.
Today, it is commercially cultivated in many countries in the tropics and subtropics, mostly in California (US), Mexico, Chile, Israel, Spain, Australia and South Africa.
In the year 2000, the world production of avocados was estimated to be 2 million tons, a figure that is now assumed to have doubled.
The avocado tree needs a nutrient-rich soil with a good drainage and grows best in sunny and wind protected areas.
Description: Avocado is a thick and richly branched tree that can grow up to 15 to 20 meters in height. Commercially grown trees are usually kept to 3-4 meters.
The leaves are oval to elliptical, pointed, dark green on the uppers side and light green underneath. They are 10-25 cm long and have a leathery surface, a bit like bay laurel leaves (Laurus nobilis).
The small, greenish-yellow flowers sit in clusters and are followed by oblong to oval, spherical or pear-shaped fruit, up to 12 cm long. The avocado tree produces fruit first after reaching five years of age.
The color of the fruit can vary greatly, depending on the plant variant/species. The fruit can be green, yellow-green, dark purple, green, reddish-brown, brown or almost black.
The pulp is white, yellow or lime green. It has a creamy texture and a nutty flavor. Each fruit contains one large seed that is easy to remove when the fruit is ripe.
Plant Parts Used: The fruit, bark, leaves, oil and seeds are used as food and/or herbal medicine.
The fruits are picked unripe for export or mature to be used for its oil.
The leaves are collected during the growing season and dried for later use in infusions, teas, and extracts.
The bark is harvested from young branches after pruning and used in decoction and an oil is extracted from the seeds which is primarily used in cosmetic products.
The avocado fruit has high nutritional levels and is primarily used as food. To speed up the ripening of a hard and unripe avocado fruit, it can be placed in a paper bag with a banana and kept at room temperature until it softens.
Common Therapeutic Uses and Health Benefits of Avocado
Active Ingredient and Substances: The leaves contain essential oil (with estragole, caryophyllene and eugenol), flavonoids (afzelin, cynaroside, luteolin, quercetin), tannins and procyanidins.
The avocado fruit is considered one the most nutritious of all fruits and very high in calories (220 kcal per 100 g). The fruit contains a fatty oil based on linoleic acid, linolenic acid, palmitic acid, stearic acid and other fatty acids, both saturated and unsaturated.
Furthermore, it contains phenols (caffeic acid, chlorogenic acid, p-coumaric acid), alpha-carotene, beta-carotene, folic acid, pantothenic acid, fructose, glucose, sucrose, fibers, amino acids and small amounts of coenzyme Q10. The avocado pulp contains more protein than any other fruit.
The fruit is loaded with vitamin B1 (thiamine), B2 (riboflavin), B3 (niacin), B6, C, D, and E (tocopherols, tocotrienols) and minerals such as calcium, sodium, potassium, zinc, iron, phosphorus, copper, manganese and magnesium.
Avocado oil containing 20-35% saturated fatty acids (palmitic acid, myristic acid, and stearic acid), 70 to 85% monounsaturated fatty acids (oleic and palmitoleic acids) and 10-15% polyunsaturated fatty acids (linoleic and linolenic acids).
In addition, it contains 5-8% glycerin, lecithin, beta-carotene and vitamin D. If the content of saturated fatty acids exceeds 20%, the oil will harden when refrigerated.
The oil has a long shelf life, around 2-5 years, provided that it is kept in a fairly cool and dark place in an airtight container.
Application of the Leaves, Bark and Seeds of Avocado
The indigenous people of Central America have grown avocados since time immemorial.
There it has been regarded for centuries as an aphrodisiac, which might explain the name “avocado”, an Aztec word for testicle, but that could also be due to the shape of the fruit.
In areas where avocado is found growing in the wild, the fruits and other parts of the tree have been used as herbal medicine for a very long time.
A tea made from the leaves has been used to treat diarrhea, bloating and flatulence. It is also thought to be beneficial as a remedy for coughs and gout by removing uric acid from the body. The tea is also used to cleanse the liver and reduce high blood pressure.
Herbal teas of avocado leaves have been known to accelerate menstruation, which in turn can cause abortion and explains the traditional use of it in Mexico to treat menstrual disorders and as a contraceptive agent.
Laboratory experiments have shown that extracts of avocado leaves effectively inhibit herpes simplex virus type I and II, which causes cold sores (I) and genital herpes (II).
The avocado seed has antibacterial and antifungal properties and has been used against diarrhea and dysentery. The fruit peel is sometimes used as a treatment for intestinal worms, and the pulp is considered to have sex stimulating properties (aphrodisiac).
Few medicinal applications of the leaves, bark, and seed have been scientifically studied by using human subjects, but the blood pressure lowering, antiviral and anti-inflammatory effects of the leaf extracts have been documented by using animal models.
A Remedy for High Cholesterol
Although the avocado fruit is mostly used as food, it does have medicinal uses as well. It has been shown to have cholesterol lowering effect which seems a little paradoxical as it is so high in fat.
In one small scientific study, 16 males aged 27 to 72 years, were given different amounts of avocado (½ to 1½ fruits per day). Half of them showed a considerable reduction in cholesterol and none of the participants experienced an increase.
In 1992, a similar but much larger study was conducted in Mexico. In the overall diet, the participants were given, 30% of the total calories came from fat, where 75% of the total fat came from avocados. After two weeks, a significant decrease in cholesterol levels was noted, especially in the LDL (the “bad” cholesterol). The level of triglycerides (fats circulating in the blood) had also decreased.
Based on these studies, a diet that includes avocados might not be such a bad idea for people suffering from high cholesterol or high levels of triglycerides.
Atherosclerosis, Angina Pectoris and Alzheimer’s Disease
The fruit contains alpha-carotenes, which have antioxidant properties and may protect against oxidation of the “dangerous” LDL-cholesterol, and thereby reduce the risk of atherosclerosis.
Eating plenty of avocados could therefore be a good dietary advice to prevent atherosclerosis, hypertension and coronary heart disease.
in addition, the iron present in the fruit is rather easily absorbed so those suffering from iron deficiency, anemia or who just need some extra iron like menstruating and pregnant women might consider including avocados in their diet.
Consuming avocados could also be beneficial for people with angina pectoris due to atherosclerosis.
In a US study involving more than 11,000 people concluded that those with the highest values of alpha-carotene in their blood had a significantly lower risk of angina compared to those with the lowest levels.
Low levels of antioxidants in the blood may also play a role when it comes to the development of Alzheimer’s disease. Studies have shown that alpha-carotene content in the blood is most of the time significantly lower in those who suffer from this disease than in healthy people.
Good for the Digestion and Blood Sugar Balance
The avocado fruit is thought to be of benefit for people with ulcers or gastritis because of its alkaline properties and due to the softening and protective actions of the fat on the mucous membranes.
Studies have shown that consumption of avocados can help maintain optimal blood sugar levels and that the fruit may, therefore, be beneficial for diabetics.
Skincare Using the Pulp of Avocado
The mashed pulp can be applied directly to the skin as a soothing remedy and protection for sunburns, suppurating wounds, and skin irritations. It can also be massaged into the scalp get rid of dryness or possibly to improve hair growth.
A soothing and cooling facial mask for dry or aging skin can be made by using mashed avocados, egg white, egg yolk or honey.
One method in traditional herbal medicine is to apply the pulp directly on dry skin spots caused by psoriasis.
Avocado Oil Uses in Aromatherapy, Cosmetics and Skincare
Avocado oil has become very popular as a natural carrier oil and it is used in different combinations as a base oil in cosmetics and aromatherapy.
It is a widely used as an ingredient in natural skin care lotions, liniments, hair products, massage creams, muscle oils, soaps, and shampoos.
The ripe avocado fruit contains 15-20% oil. The oil can not be extracted from the fresh pulp since it contains too much water that the oil emulsifies. Therefore, the pulp is quickly dried in order to increase the fat content by 40-80% in weight.
The oil is extracted through cold pressing, then filtered and refined. The oil, which is initially green, smells and tastes like avocado After refinement it is light yellow, odorless and tasteless. The refined oil is therefore very suitable for use in cosmetic products.
Avocado oil is gentle, vitamin-rich, protects the skin and makes it soft. The oil disperses effectively on the skin and although it is quite oily, it is absorbed quite well.
The oil is especially good for dry and aging skin, dermatitis and sun damage skin.
Avocados as food
When buying avocados as food from stores and supermarkets it is best to choose fruits without blemishes or damage to the shell. The color of the shell gives no indication of whether an avocado is ripe or not because the color of different varieties can vary from fresh green to almost black.
If the fruit is very soft, it is usually overripe. Hard, unripe avocados need to sit at a room temperature for a few days to soften, but if they are placed in a refrigerator whey will not ripen.
Ripe avocados will keep up to 4 or 5 days in a refrigerator. To prevent the pulp from becoming dark when exposed to air, a lemon juice, lime juice or vinegar can be squeezed on the pulp.
Avocados are great additions to salads. The pulp can be used on bread as a substitute for butter or margarine. They can be sliced in two and eaten fresh as they come, with a little salt, pepper and lemon juice added on top.
Some people prefer to use sugar on avocados, and the fatty pulp can be made into a puree for use in milkshakes and ice creams.
With 2.3 mg vitamin E per 100 g, the avocado is one of the richest fruit in this vitamin. No animal food (eggs or butter) come close to this amount. In the plant kingdom, it is only nuts and olives that surpass avocados in vitamin E content.
The avocado, along with banana, is the fruit with the highest amount of vitamin B6 (0.5 mg per 100 g), it even outdoes beef. Avocados have also high content of iron (1.02.mg per 100 grams). With 5% or more of fiber, avocados are also the most fiber rich of all fruits
Based on the fruit’s high nutritional value it could make an excellent addition to the diet of children, adolescent, athletes, overworked adults, the elderly and others who are in need of a plentiful supply of nutrients or who want to increase their vitality in a natural and healthy way.
Growing Avocado Indoors
It is possible to grow avocados as a houseplant, but the plant will eventually be too large to have indoors.
The plant is propagated by the large seed from a ripened fruit and placed shallowly in a peat mixed, moist soil. Once the plant has reached 30-40 cm in height, the top is cut so that it branches off.
The plant should be placed in a bright and warm place, have plenty of water and be transplanted into a larger container each year.
The tree will not bear fruit unless there is more than one tree for cross pollination.
Avocado trees are prone to attacks by certain insects like whiteflies when grown indoors.
As a tea: 3 or 4 leaves in two cups of water that is boiled for five minutes. Then steep for few minutes. As a remedy for diarrhea, a half a cup three times daily can be used.
To reduce high cholesterol, ½ -1 ½ avocado daily has been recommended.
Many nutritionists recommend avocado-enriched diets. (75% of the fat coming from the avocado).
Side Effects and Interactions of Avocado
Avocado fruit is safe to eat, but it can cause allergic reactions in sensitive people.
Also, the fruit has a very high nutritional content and can cause weight gain if consumed regularly along with normal amounts of food rich in carbohydrates.
The leaves and bark should not be used by pregnant women as they might cause abortion. This does not apply to the fruit.
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