Robert Downey Jr. Tried and Failed to Go Vegan: "It Just Doesn't Work for Me"

Alongside his Oscar nomination for Oppenheimer being announced, Robert Downey Jr.’s new book Cool Food: Erasing Your Carbon Footprint One Bite at a Time hits shelves today. The book, co-authored by journalist Thomas Kostigen, presents practical sustainable shifts that are easy to incorporate into most eating patterns and lifestyles.

“Cool food is really about lifestyle—transformational shifts from little actions, experiences and different choices,” Downey writes in Cool Food’s introduction. “It’s a holistic approach to making the world a whole lot better by simply making more informed decisions about something that each and every one of us does anyway—eat.”

Within its pages, delicious recipes, expert advice and personal insights are shared, making it a coffee table book guests will be excited to pick up. And if you’re thinking that the text’s approach to sustainable eating is just another fear-mongering work to promote veganism, that’s where you’re mistaken.

While a vegan diet can be a healthy choice for some and is one of the most environmentally conscious eating patterns, it can be hard to follow—including for Downey and for his health.

“I tried going all-in vegetarian—even vegan—but it just doesn’t work for me,” the actor admits. “Without some animal protein, I find myself with low levels of vitamin B12, calcium, iodine and iron. These are common deficiencies that can result from vegan diets.”

Downey is right, in that, if you’re not taking a supplement or focusing on plant-based foods that have enough of these nutrients, going vegan can result in iron deficiency, calcium deficiency and other related concerns. For his own health and desired sustainable eating pattern, the actor has decided on a happy medium.

“The rumors are true: I’m a pescatarian. That means I eat fish every now and again,” Downey says, later emphasizing for his Iron Man fans that “yes, in case you are wondering, I do actually need the iron that animal protein provides.”

A pescatarian diet includes seafood in an otherwise vegetarian diet, so it omits red meat and poultry from the meal rotation. Like other plant-forward eating patterns, the pescatarian diet can provide some positive health benefits, including longevity, steadying blood pressure and lower risk of some cancers.

You don’t need to restrict yourself to a specific diet in order to highlight eco-friendly choices in your food and everyday life, and Cool Food makes that clear. It’s all approachable steps, and Downey chose a healthy eating pattern that complemented his well-being and values. We applaud him for that. For more information on how your food choices can help fight climate change, check out these 5 easy steps you can take to reduce your carbon footprint.

And for more insights on Downey’s favorite snacks (spoiler alert: two scoops of almond butter is his go-to midnight treat!) and his family’s mindfulness approach to eating, check out Cool Food, now available for purchase.