Imagine if we could take more than 50 million fossil-fuel-powered cars off the road—not by replacing them with EVs or rewriting transportation policy, but by changing what just a fraction of the world’s cattle eat. That’s the potential of Methane Tamer™, our seaweed-based feed supplement made from Asparagopsis. And while that claim might sound bold, the math behind it is grounded in peer-reviewed science and well-established emissions data.

Let’s start with the basics. There are about 1.5 billion cattle in the world today, according to Our World in Data. Each one produces roughly 100 kilograms of methane per year through enteric fermentation—the natural digestive process in the cow’s stomach—and the overwhelming majority of it is burped out by cows. That methane has a global warming potential 28 times greater than carbon dioxide over a 100-year period—a metric known as GWP100, or Global Warming Potential over 100 years, as defined by the Intergovernmental Panel on Climate Change (Fifth Assessment Report, 2013). Even though cows aren’t burning fossil fuels, their burps are a major contributor to climate change—accounting for well over a quarter of human-driven methane emissions globally.

That’s where Methane Tamer™ comes in. Studies have shown that supplementing cattle feed with small amounts of Asparagopsis can reduce methane emissions by up to 90%. In particular, research from Kinley et al. and Roque et al. provides strong evidence for this breakthrough. But to be conservative in our modeling, we assume a 70% reduction rate. That means each treated cow would emit 70 kilograms less methane annually—or 1.96 metric tons of CO₂-equivalent.

Now, let’s scale that. If Methane Tamer™ were adopted by just 10% of the world’s cattle—about 150 million animals—it would prevent 294 million metric tons of CO₂-equivalent emissions every year. According to the EPA’s Greenhouse Gas Equivalencies Calculator, that’s the same as taking 68 million cars off the road or planting 4.8 billion tree saplings and letting them grow for a decade.

So why do we say, “more than 50 million cars”? Because we want to stay conservative—not only in the reduction rate we use, but in how we describe the outcome. The actual number is closer to 68 million cars, but rounding down helps us avoid overstatement while still communicating the enormous potential of this solution in relatable terms.

Methane is our best near-term lever for slowing the rate of global warming, and cattle are one of the single biggest sources of it. That’s why we’re focused on getting Methane Tamer™ into the hands of farmers and feedlots around the world. With just 10% adoption, we can make a measurable dent in the climate crisis. The science is solid. The opportunity is real. And the time is now.