As the poster child of millennial healthy eating,

this superfood is now a mainstay for foodies everywhere.

But have you noticed your avo on toast

is costing more and more?

Avocado prices have rocketed in recent years by up to 129%,

with the average national price of a single Hass avocado

reaching $2.10 in 2019, almost doubling in just one year.

So, why are avocados so expensive?

Archaeologists in Peru have found domesticated avocado seeds

buried with Incan mummies dating back to 750 BC.

But it was the Aztecs in 500 BC who named it āhuacatl,

which translates to "testicle."

When Spanish conquistadors swept through Mexico

and Central America in the 16th century,

they renamed it aguacate.

The farming of aguacate developed

over the next few hundred years,

predominantly in Central America and South America.

But consumption of the "alligator pear"

outside of these regions before the late 19th century

was almost nonexistent.

The commercialization of aguacate began in the early 1900s

but was focused on branding avocados as a delicacy

for the wealthy, like this advert in The New Yorker

from 1920, which declared them as

"The aristocrat of salad fruit."

But a selection of Californian growers realized

that the hard-to-pronounce aguacate was off-putting

for the mass market, so they formed

the California Avocado Association.

By the 1950s, production scale grew,

and avocado prices fell to about 25 cents each.

Popularity increased further with the wave

of inter-American immigration in the '60s,

as Latin Americans brought their love of avocados

with them to the US.

But as demand increased, supply had to keep up,

and the true difficulties of yielding large-scale

avocado crops began to show.

Avocado orchards require an extraordinary amount

of costly resources in order to flourish.

Gus Gunderson: There are multiple inputs

that avocados require,

whether it's water, fertilizer, pruning, pest control,

the sunburn protection of trees.

All those go into making your chances better

of having a very good-quality crop.

When we decide to plant an avocado orchard,

we'll plant trees that come from certified nurseries.

We have to place our orders years in advance.

On average, if we're producing 100,000 pounds per acre,

that takes about a million gallons of water,

so 100 gallons per pound,

so it'd be about 50 gallons per 8-ounce fruit.

But that's dependent on what mother nature

will throw at you, you know, we have wind,

we have intense sun.

It's really hard for a grower to manage

the unmanageable things that will affect a crop.

Narrator: The surge in popularity of avocados

stalled during the fat-fighting frenzy of the 1980s,

with an average of only 1 pound per capita

being consumed in America by 1989.

The decade's low-fat obsession drove consumers

away from avocado because of its high fat content,

without really understanding

the nutritional truth hidden within.

Hazel Wallace: When it comes to fat in food in general,

people tend to get a little bit concerned

because we often hear in the media

that fat isn't good for us.

But the type of fat that's in avocados

is monounsaturated fat, which is actually often deemed

healthy fat or heart-healthy fat,

so while there is a lot of fat in avocados,

it's actually quite good fat.

Avocado started its meteoric comeback

at the turn of the millennium, and it was helped

by an unlikely political decision.

In 2005, the US Department of Agriculture

lifted a 90-year-old ban to allow the importation

of Mexican avocados to all 50 states.

Initially, this decision angered Californian growers,

who feared the move could slash local growers' sales

by as much as 20%.

What actually had transpired and took place

was, as that Mexican supply became much more

prevalent and available, retailers got behind

marketing and selling avocados,

food service providers, restaurants started putting it

as permanent parts of their menus,

and demand started to boom

because the inconsistent supply chains before

were now consistent, and consumers were allowed

to enjoy avocados every day of the year.

Narrator: The biggest day of the avocado calendar

became Super Bowl Sunday, when it's now estimated

that almost 200 million pounds of avocados

are eaten during the big game in America.

But if you take a moment to consider

the resources needed to produce that amount,

you can start to understand avocados' elevated prices.

According to experts, it takes roughly 270 liters of water

to grow a pound of avocados.

So 200 million pounds could require

as much as 54 billion liters of water,

which means droughts or heat waves can have

devastating consequences on the avocado industry.

In fact, that's exactly what's been happening in California

for the last seven years, with the Sunshine State

only recently being declared drought-free in 2019,

which goes a long way to explaining record avocado prices.

In some countries, like Chile, avocado cultivation

is being blamed for exacerbating droughts,

as lush green orchards overlook dry riverbeds.

Perhaps the biggest reason for avocados' rise to dominance

is the emergence of the clean-eating lifestyle.

No longer just a chip dip for special occasions,

this superfood can be found in a plethora of recipes

in cafés and restaurants everywhere around the world.

And those who are eating them are really keen

for you to know about it.

Just type #avocado into Instagram, and you'll be hit

with over 10 million search results.

But is the glorification of avocado justified?

There's quite a big hype around avocados,

but it actually is quite justified when it comes

to how nutrient-dense this food is.

There's not many foods that actually replicate it

in terms of a nutritional profile.

When it comes to calling something a superfood,

I'm not really for that label.

Avocados are definitely a good food

to include in your diet, but like I said,

you're not really missing out if you don't like them

or if you can't eat them for any reason.

Monounsaturated fats, we can find that in things

like olive oil and olive, nuts, and seeds.

The vitamins and minerals, we can find that

in other green vegetables, so spinach and broccoli

and things like that.

So there's ways of getting those nutrients in

without having avocado.

All of this produce requires

an astonishing amount of labor.

Even once grown, pruned, and picked,

avocados need costly distribution methods

in order to be delivered fresh and ripe

to far-flung corners of the world.

If you're living in Philadelphia, right?

You wanna buy a ripe avocado in Philadelphia?

What they do is they ship green avocados

from California to Philadelphia,

they send them to the ripening center,

they warm them up and get ethylene in them,

so they all ripen, and then,

when they're moved out to the retail stores,

you're actually buying something

that's almost ready to eat or ready to eat.

Cause if you were to buy a green avocado that's shipped

straight from California to your market,

you would have to ripen it yourself

over a seven- to 10-day period,

and most consumers are a little more anxious

for their avocado toast than waiting 10 days. [laughs]

Narrator: With prices so high, the commodity of avocados

has attracted a spate of thefts from orchards

and delivery trucks worldwide.

In New Zealand, armed night patrols and electric fences

have been introduced after a grower in Northland

had 70% of his orchard stolen.

There's even further grim reading for avocado lovers.

In Michoacán, where 80% of Mexico's avocados originate,

cartels run a so-called "blood avocado" trade,

violently enforcing a nonnegotiable extortion fee

from farmers based on the size of their land

and the weight of their crop.

Some restaurants have begun an avocado boycott,

as we all weigh the ethics behind our eating habits.

Experts suggest that water shortages

could affect 5 billion people by 2050,

and rainfall in the so-called drought belt,

which includes Mexico and South America,

is predicted to decline.

But whilst evidence of environmental degradation

is mounting, the avocado industry is still growing

along with consumer demand.

In certain places, the sustainability of avocado production

will become untenable.