Some of the country’s biggest food companies are making a small dent in their greenhouse gas emissions, but most are failing to make critical reductions, even as consumers and government regulators push harder.

The investor advocacy group Ceres has tracked whether the 50 largest North American food and agriculture companies have set targets for disclosing and lowering their emissions. In a new report released this week, Ceres analyzed if those targets actually resulted in lower emissions.

“This is the first time we, or any organization we know of, has assessed whether company emissions in this sector are actually decreasing,” said Meryl Richards, a program director at Ceres.

Ceres’ analysis says the answer is yes—sort of.

Greenhouse gas emissions are grouped into scopes. Scope 1 emissions come from a company’s direct operations, Scope 2 from its energy use. But most emissions linked to food and beverage companies come from their supply chains, or Scope 3 emissions—from farmers who grow crops or raise livestock. If a company’s suppliers raise crops or cattle on deforested land, emissions will be higher because of the carbon released when forests are cut. That’s part of why the global food system is responsible for up to 40 percent of greenhouse gas emissions.

In the food industry, Scope 3 represents about 90 percent of a company’s overall emissions.

“The takeaway is progress on Scope 1 and 2—operational emissions and emissions from electricity use, but a lack of progress on Scope 3,” Richards said. “Those supply and value chain emissions [are] holding companies back from making progress on overall emissions reductions.”

“If you don’t have a target and don’t know what you’re aiming for, you’re much less likely to be heading in the right direction.”

— Meryl Richards, a Ceres program director

Ceres found that of the 50 food companies it tracks, 23 reduced their Scope 1 and 2 emissions over the past two years, but only 12 had reduced their Scope 3 emissions. Companies have more control over Scope 1 and 2 emissions and can reduce them by switching to renewable energy or more energy-efficient production processes, but emissions from their supply chains are tougher to tackle.

The companies that lowered Scope 3 emissions set goals.

“If you don’t have a target and don’t know what you’re aiming for, you’re much less likely to be heading in the right direction,” Richards said. “The companies making progress are the ones prioritizing it.”

Ceres highlighted companies like Kraft Heinz, McDonald’s, Hershey, General Mills, and Starbucks for setting targets to reduce Scope 3 emissions. Grain trading giant ADM actually reduced them. However, Ceres did not share individualized data or a full list of companies that reduced emissions.

The findings suggest reducing Scope 3 emissions is especially challenging for companies relying on supply chains linked to carbon-intensive commodities, like meat, or crops linked to deforestation, both of which release greenhouse gases. The challenge extends to the banks and financial institutions that invest in global agriculture.

In March, the U.S. Securities and Exchange Commission finalized rules requiring companies to disclose their climate risk to regulators. These requirements, similar to those in the European Union, force companies to disclose emissions and transition plans for reducing them, adding more pressure on food and agriculture-based companies to shrink their carbon footprints.

At the same time, because the commodities they rely on are so weather-dependent, food and agricultural companies are uniquely vulnerable to climate change-induced weather extremes that are increasingly battering farm and livestock systems.

“We have to reduce emissions from this sector if we’re going to limit warming to 1.5, or even 2 degrees,” Richards said. “The sector is so exposed. It’s also part of the solution. If none of these companies address these emissions, they’re essentially digging their own grave.”