No fish to eat will cause malnutrition

No fish to eat will cause malnutrition

If you don’t have fish, you’ll get malnutrition.

A new study of common wild fish in the Amazon region of Peru shows that if fish biodiversity continues to be lost, people there may suffer severe nutritional shortages, and the use of aquaculture and other alternatives may not be able to make up
.

This research was published in "Science Progress" a few days ago

The author of the paper studied the Loreto region, where most of the 800,000 residents ate fish at least once a day, an average of 52 kilograms per year
.

This is not only the main source of protein, but also contains fatty acids and essential trace minerals including iron, zinc and calcium

Amazonian fisheries have long been the mainstay of local residents, but there are many sources of threats to them: new hydroelectric dams obstruct large migratory fish; deforestation leads to soil erosion in rivers; mineral toxic runoff; and fishermen themselves strive to feed their fast growth Population and over-exploitation
.

In Loreto, catches are stagnating; some large migratory species are already declining, while others are about to go through this process

Shahid Naeem, co-author of the study and director of Columbia University’s Center for Sustainable Research on the Earth’s Environment, said: “Different types of plants and animals contain different nutrients, so biodiversity is the key to adequate human nutrition
.

If there are fewer fish, the quality of the diet will be affected.

In order to study the fish in this area, the lead author of the paper, Columbia University Ph.
D.
Sebastian Heilpern repeatedly bought the main food species of the local residents in the retail market, and finally obtained 56 of the more than 60 species
.

Subsequently, each is analyzed in the laboratory for protein, fatty acid and trace minerals

In general, the biomass of fish caught in recent years has remained stable
.

However, the proportion of large migratory species most susceptible to human activities is shrinking

Moreover, the researchers found that many small fish actually contain higher levels of omega-3 fatty acids, so their "takeover" may actually increase the supply of these nutrients
.

On the other hand, they said, as the species composition depends more on smaller fish, the supply of iron and zinc has declined and will continue to decline

Heilpern explained: “Some are rising, some are falling
.

But this situation can only continue to a certain extent
.
” When other species decline, it is difficult to predict which species will fill the remaining gaps, but the researchers predict that the capture The total nutritional value of the food will drop sharply when 40 of the 60 food species become scarce or become extinct
.
"

One possible solution is: when wild foods are reduced, people are increasingly turning to farm chicken and aquaculture
.
However, the researchers found that this is also destroying human nutrition
.

Researchers observed that from 2010 to 2016, chicken production in the Loreto region increased by about 3/4, and aquaculture almost doubled
.
But when analyzing the nutritional value of farmed animals, they found that the nutrition they provide is usually worse than that of various wild fish
.

In particular, the switch to chicken and aquaculture may exacerbate the already severe iron deficiency in the region and limit the supply of essential fatty acids
.
They said that because no one species can provide all the key nutrients, species diversity is needed to maintain a nutritious diet
.

In addition, chicken farming and aquaculture put far greater pressure on the environment than fisheries
.
Heilpern said that in addition to encouraging deforestation to produce feed for animals, animal husbandry also generates more greenhouse gases and introduces fertilizers and other pollutants into nearby waters
.

The significance of this research goes far beyond the Amazon
.
About 2 billion people in the world depend on non-grown food; inland fisheries alone, there are about 60 million people in the industry, providing 200 million people with a major source of protein
.
And also because the diversity and abundance of wild food harvested in rivers, lakes, and land around the world is declining
.
(Source: Wang Fang, China Science News)

Related paper information: https://doi.
org/10.
1126/sciadv.
abf9967

https://doi.
org/10.
1126/sciadv.
abf9967