Health and Human Services Secretary Robert F. Kennedy Jr. directed large food corporations to remove artificial dyes from their foods or have the government step in to do it for them.

Kennedy on Monday asked leaders of PepsiCo, General Mills, Tyson Foods, Smucker’s, Kraft Heinz, and Kellogg’s, companies which he has accused of making people sick, for commitments to reduce food additives in their products. Removing artificial dyes from processed food is a pillar of the “Make America Healthy Again” movement.