For many people trying to reduce or eliminate their meat intake, fish and other seafood tend to end up being their protein source of choice. Touted as a “health” food, there is a misconception that fish doesn’t cause the same environmental damage as eating other sources of animal protein, such as pork and beef. Unfortunately, that couldn’t be further from the truth.

recent study by researchers at the Johns Hopkins Bloomberg School of Public Health Center for Livable Future found that farmed fish and shrimp convert protein and calories from feed to edible seafood at similar rates to livestock, such as cattle, pigs, and chickens. In the case of cows, it takes around 100 calories to produce just three calories of beef. In other words, producing farmed fish is as inefficient as raising livestock.


The study highlights new insights into “feed conversation efficiency,” or in other words, the efficiency of the process by which feed is turned into meat. The team was able to access the protein and calorie content of feed inputs for fish and seafood and compare how the protein and calories are retained in the final edible product by collecting data on feed composition, feed conversion ratios, edible portions, and nutritional content.

By looking at the average protein and calorie retention across nine types of farmed fish and shrimp, researchers found that it was lower than chickens and similar to pig and cattle production.

“We face the challenge of feeding a growing human population, and aquaculture is viewed as a solution due to favorable feed efficiency compared to livestock,” said Jillian Fry, PhD, director of the Public Health and Sustainable Aquaculture Project at the Center for a Livable Future and faculty member in the Bloomberg School’s Department of Environmental Health and Engineering. Looks like factory farmed fish isn’t the silver bullet people hoped for.

Not only is aquaculture inefficient, the practice is also causing biodiversity concerns, habitat destruction, and unbalanced ecosystems. It’s also worth noting that the high-levels of plastic in the oceans and waterways inevitably make their way into seafood. It’s estimated that a person who consumes seafood regularly also eats around 11,000 pieces of microplastics a year – yuck!


The reality is, our appetite for fish is causing more harm to the environment than good. The average person in the U.S. eats around 225 fish a year, with about 43 million tons of seafood consumed globally in 2009. Many scientists have predicted that fish stocks in our oceans will collapse by the year 2048 due to our increasing demand for salmon and tuna. With the world’s population set to reach 9.8 billion by 2050, we simply won’t be able to sustain more people eating a diet high in animal products. Yes, fish count in the category of “animal products.”

If we could replace all of that fish, or at least a portion of it, with plant-based alternatives packed with protein and nutrients, we could shift our broken food system to a more sustainable one and help maintain a healthy global environment. With the growing interest in plant-based foods in recent years, many are thankfully starting to realize their food choices have consequences and choosing better. So much so that the plant-based meat market is set to reach $6.43 billion by 2023.

To learn more about how you can help the environment with your food choices, check out the new #EatForThePlanet book! Help us spread the word about this important movement by sharing this information with everyone you know.


Lead Image Source: szomkat/Flickr