Supreme Court ruling on Roundup weed killer leaves MAHA leaders feeling betrayed

The Trump administration backed Bayer, the maker of Roundup, angering prominent voices in the “Make America Healthy Again” movement.

Many prominent figures in the “Make America Healthy Again” movement said they felt betrayed Thursday after the Supreme Court ruled that Bayer, the manufacturer of Roundup, did not need to warn consumers of a potential cancer risk associated with its weed killer.

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The ruling is likely to prevent thousands of lawsuits from arguing in state courts that Roundup should come with a cancer warning.

Bottles of Roundup weed killer are displayed on a shelf at a Lowe's Garden Center in Burbank, Calif., on June 25, 2026.Justin Sullivan / Getty ImagesA growing body of scientific evidence suggests that glyphosate, the active ingredient in Roundup, is linked to cancer. That has long alarmed a subset of Health Secretary Robert F. Kennedy Jr.’s followers, known as “MAHA moms,” who want to eliminate chemicals from the food supply. The group rallied in front of the Supreme Court during oral arguments in April, and a smaller cohort expressed their concerns about underregulation of pesticides directly to Kennedy and President Donald Trump at a White House meeting that month.