It's the kind of image that is really difficult to forget.

A disturbing undercover video shot by an animal rights activist released earlier this month showed pigs being subjected to horrific conditions inside one of the nation’s largest pork processing plants. The video went viral and Hormel, the sole customer of that plant, has reportedly called for tighter controls and extra training as a result.

The incident raises uncomfortable questions about how the American food system operates. Such videos might be playing a role in a significant reduction in per-capita meat consumption -- an estimated 12 percent in five years, according to the latest U.S. Department of Agriculture projections. Still, the U.S. is a world leader in meat consumption, bearing a significant environmental and public health burden.

The high demand for meat encourages the type of factory farms -- industrial operations that raise large numbers of animals for food -- associated with abusive conditions, according to Paul Shapiro, vice president of farm animal protection at the Humane Society of the United States. Until we cut back on meat even more, we’ll likely see more of the same, no matter how many whistleblower videos surface.

The Huffington Post recently spoke with Shapiro about the link between factory farming and Americans’ love for all things meaty.

HuffPost: At a recent food policy event, you said that until Americans seriously reduce their meat consumption, the sort of factory farming like what was going on at that pork plant will never stop. Could you unpack that a little?

The high demand for meat is what is driving factory farming, which is perhaps the biggest environmental problem on the planet. It’s a gigantic use of water, land and fossil fuels. Animal agriculture is the leading cause of deforestation and is responsible for more greenhouse gas emissions than the entire transportation industry combined. There’s no way to eliminate factory farming without substantially reducing our consumption of meat.

A lot of people were outraged about that plant and shared the story but do you think that will translate to forcing the industry to change?

The meat industry, as it usually does, is acting defensively in response to this recent expose. At the same time, interestingly, within a few days I noticed that this video had more than 1 million views on YouTube. No doubt, a good number of people will think twice about how much meat they’re eating. It’s too early to say if change will come about as a result. At the same time, I think a lot of consumers have even more doubts than before that the pork industry is an industry they want to be supporting.

Do you believe there is proof that those doubts are having a real impact, though?

In the last eight years, per-capita meat consumption in the U.S. has declined by about 10 percent. That is a very modest reduction but considering it had only been increasing year over year for decades, it’s certainly a positive sign. Even Hormel, the subject of this investigation has been diversifying its own portfolio to include plant-based protein, buying Skippy peanut butter for example, recognizing that the company should not be solely focused on animal-based protein. Most of the biggest meat brands, ConAgra and Kraft and others, have also diversified their own portfolios by adding plant-based protein alternatives like Morningstar Farms and Gardein. Animal protein companies see the writing on the wall that the future is going to be more plant-based.

Credit: Allen J. Schaben/Los Angeles Times via Getty Images 8,000 brown Leghorn and white Leghorn chickens roam about a cage-free aviary system barn at Hilliker's Ranch Fresh Eggs, a family business since 1942, in Lakeview, which has one barn converted to cage-free, Friday, December 19, 2014.

We’re also seeing many major companies announcing they're going cage-free in the years ahead. What does that mean for factory farming?

The more Americans learn about how abusive the meat industry is, the greater their concern is. In the past people may have had a different vision of how animal farming works, but we’ve come a long way from Old McDonald. They’ve seen the whistleblowing exposes and they’re recognizing animal cruelty is the norm, not the exception, in the meat industry. I think there’s a greater awareness on the issue and I think that’s evidenced by the fact that so many big restaurant chains like McDonald’s and Wendy’s are telling their pork suppliers they don’t want gestation crates used anymore. Other companies are saying no more cages for chickens.

I think those policies are illustrative of the changing face of our nation. People are more concerned than ever about the treatment of our animals and that is likely to lead to better treatment of farm animals and fewer of them being raised to be killed and eaten.

How do you explain the disconnect between consumer demand driving major companies to change while their meat consumption patterns are continuing to encourage factory farming? How is that gap bridged?

America is not becoming a vegetarian nation, but it is becoming a nation that is eating more vegetarian food. I think you’re right that it’s very difficult for some people for example to consider the notion of just not eating animals, but a lot of people are very happy to eat fewer animals.

If our per-capita levels of meat consumption went back even to what they were in the 1980s, it would be a big improvement. Americans eat more meat on a per person basis than any person on earth. It’s an uphill battle and more needs to be done but increasingly Americans are seeing the value both for their own health and the health of animals on our planet to eat less meat. I think there’s a big difference between vegetarianism and people eating less meat. The latter is already happening and that trend seems only to be increasing.

This interview has been edited for length and clarity.

Joseph Erbentraut covers promising innovations and challenges in the areas of food and water. In addition, Erbentraut explores the evolving ways Americans are identifying and defining themselves. Tips? Email joseph.erbentraut@huffingtonpost.com.

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