Download nutritional aspects of avacado: a review

Volume 1 │ Issue 10 │ August 2015
AMERICAN RESEARCH THOUGHTS
ISSN: 2392 – 876X
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Available online at: www.researchthoughts.us
http://dx.doi.org/10.6084/m9.figshare.1517106
NUTRITIONAL ASPECTS OF AVACADO:
A REVIEW
Dr. Anita Singh
Assistant Professor and Head of Department of Home Science
Kr. R.C.M. P.G College Mainpuri, Uttar Pradesh - 205001, India
Abstract: The greater use of whole fruit has important advantages: usefulness in human weight
control, high nutritional density, source of major antioxidants, stroke prevention, fruit protein source,
fiber source; as baby food, and other dietary benefits. Though avocados are heavy in calories, those are
nutrient dense calories. And the fats are heart healthy monounsaturated fats and omega-3. So,
avocado gives a much-needed dietary supplement. It is a food a source of protein, minerals, and
vitamins.
Key Words: avocado, monounsaturated, nutrients, antioxidants
1.
INTRODUCTION
Avocado is one such nutrient-dense fruit that play an important role in healthy diets in
pregnancy, contributing almost 20 vitamins, nutrients and phyto nutrients. Research
shows avocado eaters consume significantly more key nutrients than non-avocado
eaters [1].
Hass avocado fruit from the Persea americana tree are grown widely in Australia.
Avocado is a buttery, high-fat fruit with a pleasant, smooth texture and best known as
the primary ingredient in guacamole. Rich in monounsaturated fatty acids, avocados
provide an excellent source of balanced nutrition during all stages of life. A majority of
avocados worldwide are Hass avocados [2}. The avocado is a medium energy dense (1.7
kcal/g) fruit because it contains about 80% water and dietary fiber. Unlike other fruits,
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avocados are low in sugar and contain 15% MUFA rich oil, which helps to increase the
bioavailability of carotenoids from salads and salsa often consumed with avocados
.
[3-5]
2.
VARIETIES AND USES
Avocados can be used in many dishes such as salads, dips, appetizers, and soups or
eaten alone. The different varieties of avocado include Bacon, Fuerte, Gwen, Hass,
Pinkerton, Reed, Sharwil and Zutano. Most varieties of avocado are oval- or roundshaped with thick, rough skin.
Figure 1: Avocado Fruit
• Bacon avocado is a sweeter variety with smooth skin found in midwinter.
• Fuerte avocado is a fall to spring variety that is medium sized with neither smooth
nor rough skin. As an easy peeling variety with milk flavour and pale yellow flesh that
slices well, this variety is ideal for salads and sauces.
• Gwen avocado is similar to the Hass but slightly larger.
• Hass avocado is the main, year-round variety. Its skin is much darker and the flesh is
silky smooth with a rich and nutty flavour. These are a good choice for dips and
spreads.
• Pinkerton avocado is a winter variety that peels easily and has smaller seeds.
• Reed avocado is a rounder summer variety with less smooth skin.
• Sharwil avocado is a medium, small-stoned variety that has a nutty flavour and oilrich flesh with an easily spreadable texture.
• Zutano avocado has a lighter-colored skin and is a summer time variety.
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Anita Singh- NUTRITIONAL ASPECTS OF AVACADO: A REVIEW
3.
NUTRITIONAL BENEFITS
The avocado is almost a perfect food. It is the only fruit known which contains all the
food elements (carbohydrates, protein and fat) as well as a wide spectrum of vitamins
and minerals. Its ash value (or caloric value) is very high at 29.4%. Its nearest
competitor is the banana, with 25%. Avocados are also rich in potassium, B vitamins,
fiber and antioxidants. B group vitamin and folates are an essential nutrient for cell
division, blood production, heart health and during pregnancy. Adequate folate is
critical for the prevention of foetal neural tube defects. This fruit is high in fibres; carry
especially soluble fibre for healthy bowel function. In addition, avocados have low
levels of sugar and sodium content. Research also has identified, that as part of a
healthy diet, this natural whole food may play a role in helping to manage conditions
such as high blood cholesterol, [6-12] a risk factor for heart disease.
Nutrients and enzymes in avocado reduce inflammation in the stomach and
small intestine’s mucous lining. This also improves the body’s ability to absorb
carotenoids and nutrients. Avocado is one of the few foods that contain a considerable
amount of glutathione. Glutathione is an antioxidant that supports the liver and the
nervous system. It is responsible for replenishing and recycling other antioxidants in
the body. It is vital for a strong immune system.
Avocados combine omega-3 fatty acids with natural vitamin E, which has been
clinically proven to prevent Alzheimer’s disease from progressing and even reversing it
in its earliest stages. 50g of avocado daily, or about a 1/3 of a smaller or a 1/4 of a larger
avocado is generally recommended.
Also eating avocado during pregnancy is recommended. Expectant mothers can benefit
from the regular consumption of avocado and other plant-based fatty foods. Avocados
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Anita Singh- NUTRITIONAL ASPECTS OF AVACADO: A REVIEW
are loaded with good monounsaturated fats, which help to lower cholesterol while also
supplying the body with the essential compounds necessary for a baby's developing
brain, eyes, nervous system and fatty tissues.
4.
NUTRIENT COMPOSITION
Table1: Nutrient average quantities
NUTRIENTS
AVERAGE QUANTITIES PER 120 g SERVE
Energy (kJ / kcal)
Protein (g)
Fibre (g)^
Soluble fibre (g)
Total fat (g)
Saturated fat (g)
Monounsaturated fat (g)
1034 / 246
2.4
5.0 (17% RDI)
2.4
25.7
5.8 (23% of total fat)
15.4
Polyunsaturated fat (g)
3.2
Plant sterols (mg)*
100
Beta carotene (ug)
215
Lutein and zeaxanthin (mg)*
353
Folate (ug)^
144 (36% RDI)
Vitamin C (mg)
13 (29% RDI)
Vitamin E (mg)*
2.3 (23% RDI)
Vitamin K (ug)*
25 (31%RDI)
Sodium (mg)
Potassium (mg)
ORAC (umolTE)
5.
HEALTHY INGREDIENT CONTRIBUTION
5.1
Fiber
5
611 (15% RDI)
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Avocados have nearly twice the amount of soluble fiber found in apples. Soluble fiber
helps lower total cholesterol and bad cholesterol, therefore, reducing the risk of heart
disease and regulates blood sugar for people with diabetes. Fibre also aid in healthy
bowel function and increases satiety. Avocados provide a combination of insoluble and
soluble fibre, in total around 2g per 50g serve. [13]
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Anita Singh- NUTRITIONAL ASPECTS OF AVACADO: A REVIEW
5.2
FOLATE
The folate supplied by avocados promotes healthy cell and tissue development. This is
especially important during periods of rapid cell division and growth such as infancy
and pregnancy. Avocados are a rich source of folate with a 50g serve providing 60ug.
5.3
MONOUNSATURATED FATS
Avocados are a great source of heart-healthy monounsaturated fat. Monounsaturated
fat is a “good fat” because it helps lower blood cholesterol. Avocados contain healthy
fats with a quarter of an avocado (50g) providing 3g of monounsaturated fats.
5.4
POTASSIUM
Potassium is a very important mineral to the human body. Potassium is essential for the
proper function of all cells, tissues and organs. It is necessary for building muscle and
for normal body growth. Avocados contribute to a good potassium/sodium balance,
with a quarter of an avocado (50g) providing 245mg of potassium and less than 2mg of
sodium.
5.5
PLANT STEROLS
Plant’s sterols help reduce cholesterol re-absorption in the intestine, increasing the
amount of cholesterol excreted from the body.
[14]
Avocados naturally contain small
quantities of plant sterols, around 40mg in a quarter of an avocado (50g).
5.6
VITAMIN B6
Avocados are a good source of the water-soluble vitamin B6. Water-soluble vitamins
cannot be stored in the body and must be supplied by diet. Vitamin B6 helps the
immune system produce antibodies, which are needed to fight many diseases. The body
also uses it to help break down proteins, meaning the more protein you eat, the more
vitamin B6 you need.
5.7
VITAMIN C
Avocados are a good source of vitamin C. It is a water-soluble vitamin that is necessary
for normal growth and development. Vitamin C is one of many antioxidants that block
some of the damage caused by free radicals, which are by-products that result when our
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bodies transform food into energy. Vitamin C is also required for the growth and repair
of tissues in all parts of your body.
5.8
VITAMIN E
Avocados supply vitamin E, which is an antioxidant that protects your body from free
radicals. Vitamin E also plays a role in healthy skin and hair.
5.9
VITAMIN K Avocados contain vitamin K, which plays an important role in
helping the body with blood clotting.
6.
USES OF AVOCADO
Avocado oil and whole fruit pulp both are equally important to humans.
1. Healthy brain: The folate in avocado contributes to preventing the formation of
brain tangles that are considered a factor for Alzheimer’s. Avocados combine
brain healthy omega-3 fatty acids with natural vitamin E, which has been
clinically proven to prevent Alzheimer’s disease from progressing and even
reversing it in its earliest stages.
2. Healthy heart: Avocados are rich in monounsaturated fats that boost heart
health and help lower blood pressure. Avocado monounsaturated fats contain
the phytonutrient beta sitosterol which was clinically proven to lower LDL and
triglyceride blood levels while raising HDL.
3.
Pregnancy: Folic acid is commonly recommended for pregnant women to help
the foetus develop its brain and other vital organs. Folate plays an essential role
in the healthy development of babies, helping to create DNA, divide cells and in
the formation of the neural tube. A varied diet rich in folate may reduce the risk
of foetal neural tube defects. [15]
4. Eye health: Avocado contains the carotenoid leutein, an antioxidant that
specializes with protecting the eyes from oxidative stress damage leading to poor
vision, cataracts, and macular degeneration. The macula lutea is a yellow spot in
the centre of the retina responsible for central vision. Macular degeneration is the
result of age related damage and it impacts central vision. The macula is yellow
because it is rich in carotenoids lutein and zeaxanthin that are thought to combat
light-induced damage caused by free radicals. Avocados provide a wealth of
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Anita Singh- NUTRITIONAL ASPECTS OF AVACADO: A REVIEW
benefits as they contain carotenoids
, help boost HDL cholesterol and their
[16]
healthy fats absorb fat soluble carotenoids from other foods.
5. Blood pressure: The combination of avocado’s high potassium content, 30%
more than banana, with omega-3 and oleic acid are beneficial toward reducing
blood pressure.
6. Blood sugar: People with type 2 diabetes, consuming avocado as part of a
healthy diet may help manage blood glucose levels as well as lower cholesterol
and triglycerides without compromising blood glucose control. Avocado’s
monounsaturated fats can prevent or reverse insulin resistance, a source of type 2
diabetes. The high soluble fiber of avocado helps prevent blood sugar spikes.
7. Anti-inflammatory: Inflammation is considered the basis of most noncontagious diseases. Avocados have an abundance of plant phytonutrient
polyphenols and flavonoids, which have been discovered as anti-inflammatory
agents.
8. Anti-aging: The master antioxidant glutathione supports the liver and the
nervous system. It is responsible for replenishing and recycling other
antioxidants in the body. It is vital for a strong immune system, and avocado is
one of the few foods that contain a considerable amount of glutathione.
9. Digestion: Nutrients and enzymes in avocado reduce inflammation in the
stomach and small intestine’s mucous lining. This also improves the body’s
ability to absorb carotenoids and nutrients. A study’s participants who ate salads
with avocados absorbed five times the amount of carotenoids than those who did
not include avocados. Carotenoids include beta carotene and lycopene. Beta
carotene is a precursor to vitamin A, and lycopene is a compound that reduces
stroke and prostate cancer risks.
10. Cancer: Avocados can help protect against prostate and breast cancers.
CONCLUSION
Dieticians can recommend consumption of avocados as part of a healthful diet that
focuses on increased fruit and vegetable intake. Avocados can be incorporated into the
diets of most adults, and may be of additional benefit to those who have increased risk
for metabolic disease risk factors.
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