Press "Enter" to skip to content

Highlighting dangers of frozen fish consumption in Nigerians

Global fishing watch IranianVessel somalia

Fish is one of the cheapest sources of protein in Nigeria. In this piece, JOHN OBA, looks at the dangers of frozen fish consumption on human health.

Fish is an important source of the household cheap proteins in Nigeria. In fact, it accounts for around 40 per cent of Nigeria’s protein intake, with fish consumption put at 13.3 kg/person/annually.

Statistics put Nigeria’s fish production at a million metric tons (313,231 metric tons from aquaculture and 759,828 metric tons from fisheries) yearly, yet the country remains the fourth largest importer of frozen fishes globally behind China, Japan and the United States.

According to the FAO, around 94 million hectares are used for fishery production, and 1,477,651 people work as fishers. World Bank data also showed that Nigeria produced about 1,169,478 tons in 2018, which is about 40 per cent of total annual fish demand of about 3.4 million metric tons; the remaining 60 per cent is through importation.


Fish farming is another source of employment and business creation in Nigeria, the sector has witnessed influx of farmers due to government efforts aimed at bridging the demand deficit gap, which currently stands at about 2.5 million metric tonnes yearly.

High rate of consumption

Findings revealed that households’ expenditure on fish and seafood consumption is projected to increase by 27.16 per cent from N2.32 trillion or $5.62 billion in 2020 to N2.99 trillion or $7.23 billion in 2029 due to increase in demand for fish and seafood for different uses. Many Nigerians today consume fish because it does not contain bad cholesterol found in meat and is strongly recommended by doctors all over the world. It contains several minerals necessary for healthy living. Fish is filled with omega-3 fatty acids and vitamins such as D and B2 (riboflavin) among others. 

Fish, human sources of cancer

Despite the huge benefits of fish and fish business, experts have called attention to the dangers of eating frozen fishes, warning that all frozen fishes have traces of cancer causing PCBs mercury.

According to nutritionist, Dr. Rasheedah Sadiq, Polychlorinated biphenyls (PCBs) and Dioxins are toxic man-made industrial compounds that can build up in the fatty tissue of fishes. 

“Unfortunately, even though the use of PCBs has been banned in many places, they tend to stick around in the environment for a longer time. Fish is said to be a persistent source of PCBs in the human diet.”

She said research has shown that PCBs can cause birth defects, smaller birth weight, and delayed learning among infants, and older adults can experience reduced memory and learning as well, while dioxins are cancer-causing industrial pollutants and are some of the most toxic chemicals known to science. 

“Sadly, all frozen fishes which are no doubt wild caught fishes have traces of mercury, the cancer causing PCBs and other metals. The bigger the frozen fish, the more the mercury load (because they feed on smaller contaminated fishes). More sadly, it can’t be seen with the naked eye.

“They’re also known to be harmful to reproduction and human development. Unfortunately, fish are a major source of dioxins in the human diet.

Health practices

Dr. Rasheedah however, said healthy practices have emerged that proves it is possible to have sustainable aquaculture that is capable of providing anti-inflammatory dishes for reversing chronic diseases. 

The techniques are practiced at Pristine Skills to develop not just sustainable but SAFE aquaculture and it is strongly suggested that other aquaculturists tread a similar path.

She revealed that farm raised fishes on the other hand have many variables in control and the issues of contamination only occur “deliberately” with the use of chemical inputs.

“Once a farmer decides not to place humans in danger, fishes can be raised absolutely without chemicals as well as without Genetically Engineered species. 

“With the issue of contamination in check, farms can raise fishes, but the next challenge is the issue of infestation. 

“Both wild-caught fishes and farm raised fishes have this problem too, but it is more prominent in the latter as the fishes are raised in confined water bodies,” she said 


She said, conscious effort must be put in place by fish processors to see that the fish processing is void of the unseen eggs, even though sometimes visible worms can be yanked off. 

She revealed that conscious farmers are beginning to sensitize the public to query the origin of the fishes they purchase and be weary of what “goes into our bodies.”

She further said that farmers are not leaving any stone unturned as they work to come up with alternative health promoting strategies which are the most efficient global strategy in fish farming and that wild caught fishes can also be cured before processing 

“Fishes are crucial for our general health and can’t be abandoned, we must put all hands on deck to see that fishes live up to their medical value and are not detrimental to human health.

“The Adventist Health Study for example, has so far found that vegetarians outlive omnivores and vegans outlive vegetarians and pescatarians – people who avoid all animal products except for fish.

“Research is ongoing, and the data isn’t necessarily conclusive. However, there is a large body of evidence that for most people, fish consumption may be linked to positive health outcomes.

Farm-raised fishes

On farm-raised fishes, Dr. Rasheedah, said nutritionally, most farm-raised fishes are problematic. According to her, fish raised in these environments have been found to promote inflammation due to their higher ratio of omega 6 to omega 3 fatty acids.

“Additionally, they may have up to 20% less protein than fish that come from the ocean.

“The secret code of the problem we have today is majorly from the imbalance between the two omega fatty acids, the diet that’s been promoted is that omega 6 should be more than omega 3, so naturally, you end up in a pharmacy dealing with Inflammatory conditions like the cancers et al….”

“You may have noticed a color difference between farm-raised and wild-caught fishes. This is because fish raised on farms don’t have access to things in the ocean that would naturally give them their carotenoid-rich pink pigmentation.

“To satisfy consumers, fish farmers started adding pigmenting compounds to their feed to enhance the coloring that consumers want. These chemical dyes turn otherwise grey fish into a rich colour and are actually the most expensive part of some farm-raised feed.

“Farm-raised fish are far from sustainable, which can be seen in the feed conversion ratio it takes to produce them. 

“Fishes used to produce fish meal are otherwise threatened into extinction, and some fish farms even feed their fishes GMO soybeans and waste byproducts from factory farmed livestock,” she explained.

GM fishes

According to her, another concern in the fish farming industry is the genetically engineered (GE) fishes. She said at least 35 species of fish are currently being genetically engineered around the world. “Some of these include trout, flounder, catfish, salmon, tilapia, and striped bass.

“Many GE fishes have been engineered to have a gene for growth hormones, which speeds up maturation and results in a fish getting bigger, in the shortest time possible.

“The economic benefit of doing this is that more and bigger fishes will be available to consumers faster, just like in other livestock production. Other GE fishes have been “improved” to be more resistant to diseases, and even to have larger muscles.

“The genes being used are often sourced from other fishes, bacteria and even mice.

As for human health impacts, these remain unknown since there haven’t been any studies conducted,” she said. 

She said however that drawing from the experience of other livestock production, we do know that GE farm-raised fishes will be more susceptible to diseases, and tend to receive larger amounts of antibiotics than other farm-raised fishes.

Since our oceans are increasingly depleted, and human appetite for fish has been on the rise, the question naturally emerges: Is there a way that fish can be farmed safely and sustainably?

“With farm-raised fish production outpacing that of wild-caught fish and of global beef, the good news is that a rapidly growing conversation around sustainability in this industry has surfaced. 

“The goal of more sustainable fish farms is to raise healthy fish that don’t damage local ecosystems.

“More sustainable farms steer clear of additives, chemicals, hormones, and antibiotics, and for fish like Tilapia, they use fish feed that is mostly or entirely vegetarian.

“More sustainable fish farms are vigilant about monitoring the quality of the water and ensuring that they don’t produce levels of pollution that harm local ecosystems or native wild fish. 

“Some are in the deep open ocean, where the water is more pristine, and currents are strong and steady enough to continually flush the farms of fish waste and pests such as sea lice. Others are placed in zero-waste closed loop systems based on land.

“While practices like these can be a big step forward, the reality is that there is stunningly little government oversight of the aquaculture industry, and claims of “sustainable” may or may not mean anything 

Another worry in the sector, according to her, is that even if aquaculture were to evolve to become a model of sustainability in the future, fish eaters would still be left with another concerning problem of fish contamination/infestation.



Spread the love