Google hid the M&Ms in opaque jars and employees ate 3.1 million fewer calories

Google's famously free food perks included M&Ms dispensed from clear gravity bins scattered throughout its offices, visible and available at all times. By 2012, the company's internal food team had noticed employees were consuming a striking share of their daily calories from the free candy alone, working against Google's own parallel push toward healthier cafeteria offerings, and worried that simply removing a beloved free perk would generate backlash without actually fixing the underlying habit.

Warning labels, healthier snack placement nearby, and general wellness messaging were already part of Google's food program and hadn't meaningfully cut candy consumption, because none of them changed the basic fact that the M&Ms were sitting in plain sight and required zero effort to grab a handful of.

Google's food team ran a seven-week test in its New York office: the M&Ms weren't removed or restricted, they were simply moved out of clear gravity bins into opaque containers, while healthier snacks like dried fruit and nuts stayed visible in clear glass jars nearby.

Moved M&Ms into opaque jars while healthy snacks stayed in clear ones, so the visual cue that triggered grabbing now points to fruit and nuts.

Visible, low-effort snacks trigger automatic grabbing, not deliberate choice.

Opaque jars remove the visual cue, converting an automatic grab into a deliberate act.

Healthy snacks in clear jars absorb the redirected reflex, so the same cue now triggers healthier choices.

Keeping the candy available avoids scarcity psychology and backlash, so the change is accepted.

To reduce consumption of something you can't remove, add friction instead of banning it; people self-regulate more from 'is it worth reaching for' than from being told not to want it.

Over seven weeks in its New York office, 3,000 employees ate 3.1 million fewer M&M calories once the candy moved into opaque jars. The experiment, dubbed 'Project M&M' internally, became one of Google's most widely cited internal behavioral-design case studies and fed directly into 'Choice Architecture' guidelines the company applied to cafeteria and snack-room layouts globally — visibility and reach-distance, not availability, became the default lever Google's food team reached for first.