Hundreds of millions of people around the world depend on freshwater fisheries for their health and livelihoods.
There is some level of controversy surrounding fish consumption: What fish are most healthful to eat? What fish are safe to eat? Is it better to eat wild or farmed fish? How can the earth’s fisheries be maintained with a growing global human population in the age of climate change and ocean acidification?
Keeping in mind the complexity of the topic, here the focus is going to be on freshwater fisheries in the developing world, where the majority of freshwater fish is consumed, and how important these fish are for human and environmental health.
Nutritional Profile of Freshwater Fish
Both fresh and saltwater fish have high levels of vitamin D and protein, with low levels of saturated fats. Many fish also have high levels of omega 3 fatty acids. This general profile makes fish an important animal protein source, and a potential tool in chronic disease prevention and management.
In general the nutritional profiles of freshwater and saltwater fish are very similar, and some species like salmon can live in both fresh and saltwater. However, there are some minor differences that do typically exist between exclusively fresh and saltwater species; freshwater fish usually have higher levels of calcium and slightly higher levels of healthful monounsaturated and polyunsaturated fats than saltwater species. Many freshwater fish species also have strong amino acid profiles, meaning they are particularly good sources of complex and essential protein.
Does Eating Fish Help to Prevent Diabetes?
Research studies focused specifically on fish consumption and diabetes prevention and management, to this point have been mostly ambiguous as to their results and recommendations. While macro and micro nutrients in many fish, such as vitamin D, healthful fats and complex proteins, are all known to help in reducing the risk of type 2 diabetes onset and complications, the overall consumption of fish thus far has not been definitively connected to preventing diabetes. These inconclusive findings may be due to the large range of different kinds of fish consumed in different quantities, and the contaminants that sometimes exist in fish species in certain locations exposed to mining, industry and intensive agriculture.
Freshwater Fish in Traditional Diets
Fish within the Earth’s lakes, rivers and streams help to sustain billions of people around the world. From the Amazon River Basin of South America to the Mekong River Basin of Southeast Asia, many traditional diets are based around freshwater fish. Freshwater fish is predominantly consumed in the developing world, where the paradoxical dual-problems of food insecurity and the rising incidence of obesity and diabetes are of growing concern.
The Case of Cambodia
Inside Cambodia, the Tonle Sap Lake, which connects to the Mekong river, is the world’s most productive freshwater fishery, and subsequently Cambodians consume the largest percentage of freshwater fish in their traditional diets. If they were to lose this important protein source, due to contamination from human activities, or the blocking of migration patterns from planned hydroelectric dams, the very fabric of Cambodian diets will be destroyed.
The entire society would most likely go through expedited and destructive “Nutrition Transitions” away from their traditional diets towards highly processed foods and less healthful animal protein (if they had the resources to buy it). These dietary shifts would translate to higher incidence of chronic metabolic diseases like type 2 diabetes. In impoverished rural fishing communities in Cambodia, losing both their food supply and source of income, could lead to food shortages, hunger, and migration to the cities.
A Global Problem
The threats to freshwater fisheries and the impacts of their losses are a global problem, with Cambodia representing an important and extreme case. It is critical to preserve the freshwater fisheries of the planet, not just for human health, but for maintaining the integrity of entire ecosystems. The largest threats to freshwater fisheries, from dams to mining to industrial fishing, are the products of an unsustainable global system that causes harm to both human and planetary health.