What are the cultural patterns and values that underlie food choices in the United States, and how do they affect what you eat?

Many fish have a smaller carbon footprint than livestock. However, there is a great deal of variability. Farmed catfish produce almost as much \(\mathrm{CO}_{2}\) as beef cattle. Tilapia and shrimp farming also produce a lot of greenhouse gases. However, small fish such as anchovy and sardines, as well as farmed shellfish such as oysters, mussels, and scallops, are relatively energy efficient and do not produce much greenhouse gas. The electricity used to power fish farms is the source of much of the \(\mathrm{CO}_{2}\) produced by harvesting these smaller varieties. Thus, as alternative, nonpolluting ways of producing electricity are found, fish farming can become less environmentally hazardous (Hilborn et al., 2018).
Although some plant-based foods, like almonds, do have high resource requirements, vegan and vegetarian diets result in far less greenhouse gas emissions than diets that rely more heavily on meat and fish. Consuming a pound of nuts, broccoli, or tofu involves only about \(7 \%\) as much greenhouse gas emission as a pound of beef (Hamerschlag \& Kumar, 2011, p. 23). A study by Aleksandrowicz and others (2016) showed that vegan diets resulted in about \(45 \%\) less greenhouse gas than typical U.S. diets, and vegetarian diets, \(31 \%\) less. But even just replacing beef and lamb with pork and poultry results in a \(21 \%\) decline in greenhouse gas emissions.
There is certainly a place for meat in a healthy diet, and in some places, meat production is environmentally sound. Neither of the authors of this book is a vegetarian. However, it is clear that some changes in our diets and changes to how we produce food are necessary if we are going to be able to control global warming.