From Dr. Mercola:
Plant-based diets are widely considered to be better for the environment than diets that include animal foods.
While it’s true that animal foods from concentrated animal feeding operations (CAFOs) are among the worst polluters on the planet, industrially grown plant foods, at least some of them, may not be much better (and in some cases may be worse).
Researchers at Carnegie Mellon University conducted a meta-analysis to quantify the water and energy use, along with emissions, for more than 100 foods. The largest water and energy footprint per calorie came from fruits.1
Vegetables, dairy, and fish/seafood were also found to have relatively high resource use and emissions per calorie. Study author Paul Fischbeck, professor of Social and Decision Sciences and Engineering and Public Policy, told Scientific American:2
“You cannot just jump and assume that any vegetarian diet is going to have a low impact on the environment You can’t treat all fruits and veggies as good for the environment.”
Lettuce Is a Top Source of Food Waste – and Foodborne Illness
In determining the energy footprint per calorie of the various foods, the researchers also accounted for food waste. The average calories per day consumed were calculated at 2,390, with an additional 1,230 for food waste.
Part of what makes leafy greens like lettuce so environmentally burdensome is because they’re a top source of food waste. More than 1 billion pounds of salad go uneaten every year (let the enormity of that number sink in for a minute).3 This means all the water and energy put into its production is wasted too.
There are a few reasons for this, including contaminated water used to irrigate fields and manure that may be used for fertilizer or which contaminates the field from nearby farms. Michael Doyle, director of the University of Georgia’s Center for Food Safety, told Modern Farmer:5
“We’ve already had outbreaks with cut lettuce and cut spinach and E. Coli 01:57, and there’s also salmonella, and listeria. These organisms typically come from animals; they carry them in their intestinal tracts.
When the manure gets into the environment, then the bacteria is there, in the soil or the water. Often, when manure dries out, the wind blows it. Salmonella, we know, is quite tolerant to drying.”
Another issue has to do with a milky “latex” that forms when the plant is cut, essentially trapping in bacteria that’s virtually impossible to wash off. Compounding the matter is that leafy greens like lettuce and spinach are often eaten raw. Doyle continued:
“When the latex forms, if there is harmful bacteria there, the bacteria is within the plant tissue.
The treatments that are typically used in the processing plant for cleaning is basically chlorine, and they’re just washing the outside of it, so the bacteria is not going to be washed