Is flying fish safe to eat? (Health benefits)

In this brief guide, we will answer the question “Is flying fish safe to eat?”. We also will discuss how mercury concentration can make some fish species unsafe to consume.

Is flying fish safe to eat?

Yes, flying fish are safe to eat and have a significant role in various cultures and economies. Caribbean, Southeast Asian, and Southern Pacific regions use them in traditional fisheries and it has an important role in coastal fishing industries.

Flying fish has contributed to Taiwan’s fisheries production and ranking among the top twenty species caught. The main edible species are  Spotwing flying fish (Cypselurus poeicilopterus), Limpidwing flying fish (Cheilopogon unicolor), Darkwinged flying fish (Cypselurus poeicilopterus), and stained flying fish (Cheilopogon spilonotopterus). (1)

Flying fish have an average length of 26cm and a weight of 145g, this fish has a filet yield of about 38%. They have low fat and high protein levels. The lipid composition of flying fish has total saturates making for 37.7% of fatty acids. Total monoenes are at 14.4%.

Polyenes account for 48.8% of flying fish oil. In this composition, omega-3 fatty acids make up about 40.2% of the total, with docosahexaenoic acid being the most abundant of its constituents. Flying fish protein is also rich in amino acids like aspartic acid (12.4%), threonine (5.6%), valine (6.7%), glutamic acid (18.4%), leucine (10.%), and lysine (12.1%). (2)

What are flying fish’s health benefits?

The flesh of flying fish is a valuable source of essential nutrients, including selenium and polyunsaturated fatty acids (n-3 PUFA).

Fish consumption is well-known for its positive effects on brain development in infants and fetuses, and it has demonstrated protective benefits against a range of conditions, including cardiovascular diseases, mental disorders, and various inflammatory conditions like bowel disease, asthma, and arthritis.

Fish, including flying fish, provides high-quality protein and ranks among the top dietary sources of long-chain omega-3 fatty acids, particularly DHA and EPA. These omega-3 fatty acids are crucial for a healthy diet, playing a significant role in promoting cardiovascular health, as well as supporting the development of the brain and eyes. (3, 4)

What are the potential risks of flying fish consumption?

Flying fish may contain varying amounts of contaminants, such as mercury (Hg), primarily in the form of methylmercury (MeHg), which makes up over 90% of the mercury content. This occurs because fish feed on aquatic organisms that contain MeHg originating from the biomethylation of inorganic mercury by microorganisms.

However, it’s important to note that empirical data suggests that genuine concerns about mercury exposure typically arise only when consuming fish in quantities well beyond the typical intake. 

The FDA and EPA have identified seven types of fish that should be avoided, especially during pregnancy, due to high levels of mercury. These species include shark, king mackerel, swordfish, Gulf of Mexico tilefish, marlin, orange tilapia and bigeye tuna.

These recommendations are based on the well-documented levels of mercury in these fish and the incredible benefits they provide. For this reason, flying fish are generally considered a safe choice for consumption. (4, 5)

What are the health hazards of methylmercury?

Organic mercury, especially methylmercury, affects the central and peripheral nervous systems in humans. Fetal exposure to methylmercury may have more adverse effects on the developing brain than in adults.

With short-term or long-term exposure to abnormally high levels of methylmercury, the onset of neurological symptoms is often subtle and manifests as hearing loss, restlessness and blurred vision. Other symptoms that may appear later include difficulty speaking and poor coordination.

If exposure is severe, methylmercury poisoning can cause coma and, in severe cases, death. After ingestion, organic mercury (such as methylmercury) is easily absorbed from the intestine and distributed over a wide area of the body. Methylmercury easily crosses the blood-brain barrier and placenta, posing a serious risk to health and development. (3)

What factors affect mercury accumulation in flying fish?

The presence of methylmercury (MeHg) in fish typically correlates with various factors, including the fish’s weight, age, trophic level, and species. Mercury (Hg) has historically been a part of all the world’s oceans, stemming from sources such as river runoff, undersea volcanoes, and atmospheric deposition. Over time, it has accumulated in fish at the top of the food chain.

However, in the past century, the industrialization of numerous countries has led to a net increase in the environmental mercury load, which is subsequently reflected in the mercury levels found in fish worldwide and in the individuals who consume them.

Avoiding flying fish out of concerns about excessive mercury intake is unnecessary, given that flying fish, along with barber and Bermuda Chub, have been found to have the lowest mean concentrations of mercury. Consequently, these species can be safely consumed daily without the risk of contamination. (4)

Conclusion

In this brief guide, we answered the question “Is flying fish safe to eat?”. We also discussed how mercury concentration can make some fish species unsafe to consume. In my perspective as a food scientist, flying fish is safe and can be consumed every day offering no risk.

References