Description and history
Related to bay laurel, sassafras and cinnamon, the avocado comes from a tall, tropical evergreen, Persea americana, which belongs to the Lauraceae (laurel) family (1). Originally harvested in Central and South America around 8,000 B.C, the name “avocado” is amusingly derived from the Aztec word “ahuacatl”, meaning “testicle” (2).
By the mid-17th century avocados had made their way to Jamaica and the Asian tropics but it wasn’t until the early 20th century that they sprang up in the U.S: Florida and California (3). Today, Avocados typically grow in tropical and subtropical regions but are also commercially cultivated in Mexico, the Dominican Republic, Brazil, and Colombia (4).
Typically weighing between 8 ounces and 3 pounds, the wonderful avocado is sometimes nicknamed the Alligator Pear, on account of its pear-shape and the leathery skin (5,6). From a nutritional and health benefit, raw avocado served at room temperature is said to reap the most rewards (7).
Avocados are among the few fruits with a high fat content (8) and, in fact, with fat making up 71%-88% of their total calories, they are higher in fat that most animal foods.
An average avocado contains 30g of fat, 20g of which comprises monounsaturated fats (good fats), such as oleic acid (9).
In addition to providing 20 times the fat of other fruits, avocados are packed with vitamins and minerals such as vitamins B6, C, E, K, folate, copper, dietary fibre, potassium and pantothenic acid (10).
Here’s a typical nutritional profile for 1 serving of avocado (1 avocado, 201g whole, about 70g peeled & de-seeded) (11):
- Calories: 322 kcal
- Protein: 4g
- Fat: 29g
- Carbs: 17g
- Dietary fibre: 13g (54% of RDA)
- Vitamin K: 53% of RDA
- Folate: 41% of RDA
- Vitamin C: 33% of RDA
- Potassium: 28% of RDA
- Pantothenic Acid: 28% of RDA
- Vitamin B6: 26% of RDA
- Vitamin E: 21% of RDA
- Copper: 19% of RDA
- Niacin: 17% of RDA
- Riboflavin: 15% of RDA
- Magnesium: 15% of RDA
- Manganese: 14% of RDA
- Phosphorus: 10% of RDA
- Zinc: 9% of RDA
- Vitamin A: 6% of RDA
- Iron: 6% of RDA
Due to the abundance of various nutrients such as phytosterols, carotenoids, flavonoids, and omega-3 fatty acids, avocados pack a high anti-inflammatory punch (12).
In particular, those with osteoarthritis and rheumatoid arthritis may find avocados particularly helpful in easing symptoms.
The star nutrients in avocados are carotenoids (13). These phytonutrients are fat-soluble and need an ideal blend and amount of dietary fats to be properly absorbed by the body. Avocados provide just the right amount for this, and with their oleic acid, chylomicron molecules can easily move carotenoids through the digestive tract and into the body (15).
While avocados are high in fat, it is the healthy kind, and it is a huge help to your heart and blood vessels. For example, these fruits provide a metabolic boost while lowering inflammation and oxidative risks, cholesterol, and fat levels in the blood (18).
It is proven that oleic acid (avocado’s main fatty acid) greatly benefits the heart. Combined with the fruit’s omega-3s (in alpha-linolenic form), the benefits are maximized, and you can get 160mg per cup!
Heart disease can result from high homocysteine levels and can be lowered with B vitamins. Avocados are packed with vitamin B6 and folic acid to support a healthy heart (19).
As research develops, we can expect to learn even more about the cardiovascular perks of these amazing fruits.
Blood Sugar regulation
A riveting area of avocado research relates to regulating carbs and blood sugar in the body (20). Avocados are low in carbs (19% of total calories) and sugar (<2g per cup), making it a low-glycemic food. Moreover, one cup of avocados has about 7-8g of dietary fibre, known to regulate blood sugar.
Of particular interest to researchers is that the primary sugar found in avocados is a “7-carbon sugar” called D-mannoheptulose (21). 7-carbon sugars are rarely seen in foods and are particularly important to food researchers as they are thought to regulate blood sugar and support weight management (22).
Scientists have been observing the correlation between animals and mouth, skin, and prostate gland cancer and avocado consumption (23). Their findings are promising and show that avocados have anti-cancer components, including antioxidants and anti-inflammatory compounds.
These nutrients are extremely beneficial in preventing inflammation and the growth of cancerous cells as well as killing them through apoptosis. In terms of healthy cells, avocados reduce inflammation and oxidative stress levels (24).
Although this research has been limited to animals, it holds huge potential for human health.
Avocados contain chitinases – enzymes that contribute to the generation of carbon and nitrogen in the ecosystem (25) – and are related to latex fruit allergy syndrome (26). Evidence shows a strong correlation and cross-reaction between latex and foods with increased levels of chitinases.
As such, people with latex allergies may experience an allergic reaction to avocados, as chitinase enzymes cross-react with latex. Commercially-processed avocados may contain ethylene gas, which increases the risks, although, organic avocados are usually not processed with ethylene and may be safer.
Cooking avocados is thought to reduce such allergy risks.
How to Select and Store
Avocados that are slightly soft and blemish-free are ripe for picking. Those with a pear-like neck (rather than a rounded top) probably matured on trees and may have an enhanced taste. Avocados that are firm are less ripe and can be ripened at home which can also reduce the chance of bruising.
Firmer avocados can be ripened in a paper bag or basket. Let them sit at room temperature for a few days and the skin will darken but do not refrigerate avocados until they ripen. Then, they can be refrigerated for up to 7 days. Refrigerating a sliced avocado will accelerate browning, which occurs when air comes in contact with the flesh.
If you wish to store sliced avocado, keep it refrigerated. Sprinkle it with lemon juice or vinegar and wrap it in plastic wrap or a baggie. You can also put the fruit on a plate and completely cover and seal it with plastic wrap.
To slice avocados, cut it lengthwise with a knife and gently twist the halves apart. Spoon out the pit (seed) or take it out with a knife tip. Slice the halves into quarters and peel the skin away from the flesh using your thumb and pointer finger (this is the “nick and peel” approach that the California Avocado Commission recommends.) You can then access the nutrient-rich dark green flesh and get the maximum antioxidants.
Sources Of the Article
- Authority Nutrition
- Nutrition Data Self
- Natural News
- The Journal of Nutrition
- Nutrition Journal