AVOCADOS SIDE EFFECTS, HEALTH BENEFITS AND NUTRITIONAL FACTS

Avocados side effects,
nutritional values and
health benefits

Avocados were first cultivated in South America with later migration to
Mexico. It was believed that a Mayan princess ate the very first
avocado and that it held mystical and magical powers. European
sailors traveling to the New World used avocados as their form of
butter. Avocados were first seen in the United States in the early
1800's. California is currently the largest producer of avocados
stateside. There are more than 80 varieties, with the "Hass" variety
dominating the crop share. A single mature avocado tree can produce
more than 400 pieces of fruit in a year.

NUTRITIONAL VALUES
Avocados are loaded with nutrients such as dietary fiber, vitamin B6,
vitamin C, vitamin E, potassium, magnesium, and folate. They're also
cholesterol and sodium free. Avocados contain 60% more potassium
per ounce than bananas. This fruit is an excellent source of
monounsaturated fat. In addition, researchers have shown that
avocados extracts improved calcium absorption in rats and addition of
avocado to salsa significantly improved lycopene, lutein and carotenes
absorption in healthy human subjects. [1, 9]

POTENTIAL HEALTH BENEFITS OF AVOCADO
Researchers from South Africa proposed to use Avocado (Persea
americana) leaf aqueous extract for the management of childhood
convulsion. The data from their study in rats suggested that 'avocado'
leaf aqueous extract produced its anticonvulsant effect by enhancing
GABAergic neurotransmission and/or action in the brain. [8]

Some studies show the potential benefits of soybean combined with
avocado on the symptoms of osteoarthritis. [12-15, 18] The combo is
believed to exert anti-inflammatory and stimulatory effects on
aggrecan or proteoglycan synthesis in chondrocytes. [15, 17] The
common dose of the Avocado-soybean unsaponifiables (ASU) in some
of the studies is from 300 to 600 mg/day. [16, 19]

AVOCADO MAY HAVE BENEFITS OF CUTTING CANCER RISKS
The California Hass avocado (Persea americana Mill.) avocados were
found to contain the highest content of lutein among commonly eaten
fruits as well as measurable amounts of related carotenoids
(zeaxanthin, alpha-carotene, and beta-carotene). Lutein accounted for
70% of the measured carotenoids, and the avocado also contained
significant quantities of vitamin E. An acetone extract of avocado
containing these carotenoids and tocopherols was shown to inhibit
the growth of both androgen-dependent (LNCaP) and
androgen-independent (PC-3) prostate cancer cell lines in vitro. [11]
On the other hand, Kim OK from Kyoto University, Japan, proposed
that persenone A, an active ingredient of avocado, is a possible agent
to prevent inflammation-associated diseases including cancer. They
found that persenone A at concentration of 20 microM almost
completely suppressed both iNOS and COX-2 protein expression in a
vitro study. [21]

AVOCADO HELPS CHOLESTEROL-LOWERING DIETS
Researchers found that intake of avocado could enhance the effect of
low-fat diets on lipid reduction. [22, 26] Mexican researchers consider
avocado as an excellent source of monounsaturated fatty acid in diets
designed to avoid hyperlipidemia without the undesirable effects of
low-saturated fat diets on HDL-cholesterol and triacylglycerol
concentrations. [23]

In a study of healthy adult normolipidemic volunteers and 37 adult
patients with mild hypercholesterolemia, Mexican researchers found
that intake of avocado was linked to a significant decrease of serum
total cholesterol (17%), LDL-cholesterol (22%) and triglycerides
(22%), and increase of HDL-cholesterol (11%) levels in
hypercholesterolemic subjects. [24]

EFFECTS OF AVOCADO ON WEIGHT LOSS AND BLOOD PRESSURE
The consumption of 200 g/d of avocado within an energy-restricted
diet does not compromise weight loss when substituted for 30 g of
mixed dietary fat. Serum lipid concentrations, plasma fibrinogen,
arterial compliance, and systolic and diastolic blood pressures were
not affected by weight loss or avocado intake. [10]

BIOLOGICAL EFFECTS / SIDE EFFECTS OF AVOCADO ETRACTS
AND OILS

One common side effect of avocado intake is allergy or
hypersensitivity. The symptoms include skin reactions, vomiting,
bronchial asthma, rhinoconjunctivitis, urticaria and angioedema. [25,
28] In a study, eight of the 21 avocado skin test positive patients
reported that symptoms repeatedly followed the ingestion of avocado;
two reported systemic reactions, but six noted oral symptoms only.
Serum IgE antibodies to avocado were elevated in seven of the eight
patients reporting symptoms after eating avocado. Avocado-induced
symptoms occurred in 8% of 100 consecutive atopic allergic rhinitis
patients unselected for avocado reactivity. Oral, and less frequently
systemic, allergy symptoms appear to be more common among the
atopic population than previously appreciated. [25]

In later 1980s, researchers from Israel fed rats with avocado or
avocado seed oils for four weeks and they noticed an increase in the
amount of hepatic lipids, a decrease in blood levels of triglycerides in
the animals and changes in levels of some liver enzymes. [2]

Rats fed with unrefined avocado oils showed significant increases in
soluble collagen content in skin. The increased soluble collagen
content appears to be a consequence of the inhibition of lysyl oxidase
activity. The total collagen content did not change. [4] However,
researchers also found a significant decrease in total collagen
solubility in the liver after supplementation of unrefined avocado or
soybean oil to rats for one week. They confirmed the results by
repeating the experiment with chicken. They also found collagen
accumulation in the liver of the rats, suggesting early stages of
fibrosis. [5]

Though there are indications (above) that avocado may damage the
liver by collagen formation, Japanese researchers have shown the
protective effects of avocado on liver injury caused by
D-galactosamine. [20]

The leaves of avocado in doses exceeding 20 g fresh leaf per kg
bodyweight, produced damage to the mammary gland with decreased
milk production in an animal study. [3] Six of 21 goats feeding on fresh
avocado leaves from pruned trees, showed clinical signs of cardiac
distress. [6] Ingestion of avocado leaves also caused lung oedema,
hydrothorax, severe myocardial degeneration, necrosis and fibrosis in
15 Cameroon goats. [7] In a study, nine out of 120 ostriches died from
congestive heart failure within 96 h of ingesting avocado leaves and
immature fruit in an avocado orchard containing Hass and Fuerte
cultivars.[27] Finally, researchers from Kenya observed dyspnoea,
pulmonary oedema, abdominal enlargement and signs of elevated
liver enzymes from two dogs which had a fondness for avocado fruits.
[29]

THIS ARTICLE IS FOR YOUR REFERENCE ONLY. IF YOU HAVE ANY QUESTIONS,
YOU SHOULD CONSULT WITH YOUR DOCTOR. THIS ARTICLE DOES NOT
RECOMMEND TAKING EXCESSIVE AMOUNT OF AVACODO. ALL RIGHTS
RESERVED 2008 ZHION DO NOT COPY TO OTHER WEBSITES NOR BLOGS NOR
ANY OTHER TYPES OF PUBLICATIONS.

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