Opting for small predatory fish such as herring, sardines, and anchovies instead of red meat could not only prevent 750,000 deaths a year by 2050, but also significantly reduce the prevalence of diet-related diseases, according to authors of an article published in the BMJ Global Health journal.

Low and middle-income countries, where these small fish are cheap and abundantly available, would particularly benefit from promoting a fish-rich diet, the researchers argue. Such countries currently experience a high number of fatalities from heart disease. The consumption of red and processed meats is linked to nearly 70% of global deaths from non-communicable diseases, the authors emphasize.

Coronary heart disease, stroke, diabetes, and colorectal cancer account for nearly half (exactly 44%) of these deaths, with coronary heart disease topping the list.

Why is consuming fish better?

Small predatory fish, preyed upon by larger fish, are rich in long-chain polyunsaturated omega-3 fatty acids, consuming which can prevent coronary heart disease and stroke. Additionally, the flesh of these fish is an excellent source of calcium and vitamin B12. Moreover, among all animal sources of food, these have the lowest carbon footprint, the authors add.

However, about three-quarters of the caught predator fish, including those caught near the shores of countries struggling with food scarcity and malnutrition, are currently processed into fishmeal and fish oil. These products are primarily used in fish farms, and the fish raised on these farms are then purchased by wealthier consumers.

While several studies have discussed the nutritional and environmental benefits of fish consumption, none have weighed how much replacing red meat with fish could reduce the health burdens of the world's population. The authors, therefore, outlined four different scenarios based on how the consumption of predatory fish could evolve globally. Their data draws from predicted red meat consumption in 137 countries by 2050, and the maritime registry of predatory fish consumption.

What if we ate more fish?

The scenarios covered:

1. Predatory fish are primarily used within the catching nation for national consumption and red meat replacement.

2. Predatory fish are used globally to minimize red meat consumption, prioritizing countries where lamb and beef consumption exceeds the recommended 15 kcal level.

3. The priority is increasing fish consumption in countries where it is currently below the recommended 40 kcal level.

4. Red meat is replaced with fish to a consistent degree across all countries, dictated by the globally available quantity of predatory fish.

The analysis showed that widespread direct human consumption of predatory fish could lead to significant public health benefits, especially in terms of reducing coronary heart disease.

This approach could prevent 750,000 deaths globally in the year 2050 alone, the authors project, with a significant reduction in deaths resulting from coronary heart disease. Such a change would also save between 8-15 million years lived with disease globally, which are currently concentrated in low and middle-income countries.

WE CANNOT FULLY REPLACE RED MEAT WITH FISH, BUT EATING MORE FISH CAN HELP

The researchers acknowledge that the limited availability of predator fish cannot fully replace red meat. However, it might be sufficient to bring most countries' per capita fish consumption closer to the desired 40 kcal level, reducing deaths caused by coronary heart disease, stroke, diabetes, and colorectal cancer by 2% by 2050.

Of the four scenarios, the first would prevent the fewest deaths. In contrast, the analysis suggests that increasing consumption in the lowest-ranking countries regarding fish consumption - the third scenario - would more effectively reduce the global disease burden.

In landlocked countries with no direct access to marine resources, such as Mongolia, Turkmenistan, and many African nations, the commercial trade of predatory fish needs to be amplified, the researchers point out. "Realizing the theoretical potential of predatory fish, and actualizing the health benefits they can provide, faces several barriers, including fishmeal and fish oil production, overfishing, climate change, and cultural aversions," the article states. "Some of these barriers could be overcome with cross-sector, coordinated political action. It could also be promoted by increasing access to cheap fish, especially predatory fish species, in poorer countries, as well as supporting the use of nutrient-rich microalgae in fish feed."

Cultural interventions that promote healthy lifestyles, family and community support, and illuminate the links between unhealthy eating and diseases could also bear fruit in successful lifestyle and dietary changes, the authors hope. They also believe that eco-friendly labeling of foods and educating consumers about the high nutritional value and low chemical content of predatory fish might further facilitate replacing red meat with fish.