In Planet Palm (New Press, May.), journalist Zuckerman exposes the health and environmental risks of palm oil.

What is palm oil and why is it used in so many products?

It’s a crop that’s indigenous to west and central Africa and for centuries it’s been central to their food culture and religious ceremonies, but more recently the industry has moved mainly to Southeast Asia. Palm oil is very versatile. It’s good for cookies, basically any ultraprocessed foods. It extends the shelf life and it’s slightly healthier than trans fats. It’s also used in cosmetics and other industrial products and more recently as a biofuel.

One of the book’s most compelling arguments is that the production of palm oil exists at the intersection of multiple crises—nutrition, the environment, etc. Did that surprise you?

In the introduction I refer to something that Lancet has termed the “Global Syndemic”—the overlapping 21st-century crises of obesity, malnutrition, and climate change. The health impact of this industry was one of the most surprising things. Going in I knew vaguely of the impact of deforestation on orangutans, but nobody had looked at where all this oil was going. So about two years ago I started comparing import data in different countries with rates of obesity. I could overlay these graphs on top of each other and they’d correspond almost exactly. I was astonished. I know you can’t pin the obesity issue to one commodity, but this is not something people had talked about. When we talk about the obesity crisis, you usually hear about sugar, but the growth in calories in refined vegetable oils has far surpassed that of sweeteners in the last half-century.

What do you hope your readers take away from the book? What can the average consumer do?

My main idea was just to educate people, because Americans especially know almost nothing about palm oil. I think it’s important for people to realize that it is everywhere, particularly in our foods. Read labels. If you care about deforestation, climate change, appalling labor abuses—read labels. Find out what companies are using palm oil, and demand accountability in terms of where they’re sourcing it and if they have “no deforestation” agreements. Same for institutional investors who are funding deforestation-linked palm oil. It’s hard to get involved as a single consumer, but there are a couple of organizations that are focused on this. Check out the Rainforest Action Network and Mighty Earth. They’re in touch with grassroots folks in the communities that are being impacted by this industry. They also spearhead campaigns focused on getting companies to change the way they do business, and they’re very effective.