Americans ate an average of 1,999 calories per day in 1975. That’s according to the USDA, which released updated data this month that says we’re now up to 2,481.

That increase has come with soaring rates of cardiovascular disease and diabetes, the fiscal cost of which is inordinate.

The greater threat to our health as a population, though, may be the fact that the total U.S. food supply (the amount available, both produced and imported) is now 4,000 calories per person per day, also according to the USDA. This means that close to half of that food supply is going to waste. At the same time, none of these numbers is growing as quickly as the total number of people. Between 1975 and today, the American population increased from 213 million to 319 million.

So not only are we individually increasing in mass, but our numbers are soaring. The combined result is that over the past four decades, the amount of food being produced in order to feed the U.S. population (including what goes to waste) has nearly doubled.

Agriculture is a major source of greenhouse gas emissions—not simply by ways of the methane emitted by cattle, but through the deforestation of land necessary to grow the feed for the animals, and the actual process of growing that feed. Barring a radical cultural shift away from such abundance or a re-conception of what we consider to be food, this growth does not seem to be environmentally sustainable in any humane way. Gains made by the common approaches to environmental consciousness (organic farming, local sourcing, et cetera) seem to be chipping at the periphery of the problem.

I don’t have a great solution, but I also don’t want to end on that note, so here’s a more upbeat look at the future of protein we did recently: