Eating occasions in the United States have multiplied while formal meals have thinned. The change tracks working patterns more closely than it tracks appetite or nutrition advice.
Where the three-meal day came from
Fixed mealtimes are a comparatively recent arrangement, consolidated when industrial and clerical work required large numbers of people to be in one place on a shared clock.
A factory whistle or an office lunch hour defines when eating is possible. The structure of the meal followed from the structure of the shift, not the other way around.
Agricultural households before that ate on patterns tied to daylight and labor demands, which varied by season. The rigid three-meal template was never universal.
What desk work changed
Sedentary work removed the physical barrier to eating while working. A machine operator cannot eat mid-task; someone at a keyboard can, without leaving the workstation.
Eating then stops being a bounded event and becomes something interleaved with other activity. The boundary that made a meal identifiable disappears.
Distracted eating is also poorly registered. Food consumed while attention is elsewhere tends to be under-recalled later, which matters for anyone trying to account for intake.
How the food supply responded
Manufacturers built entire categories around the new occasions: shelf-stable, single-serve, requiring no plate, no utensil and no interruption to whatever else is happening.
Packaging is the enabling technology. A food that survives a desk drawer and opens with one hand fits a pattern that a sandwich requiring assembly does not.
The category then reinforces the behavior it was built for, since availability at arm's length is among the strongest determinants of whether something gets eaten.
What remote and shift work added
Working from home removes the last external constraint, placing a kitchen within a few steps of the desk for the entire working day.
Shift work pushes in a different direction, pulling eating into biological night when digestion and glucose handling operate differently than they do during the day.
Both patterns lengthen the daily window during which food is consumed, which is the variable that time-restricted approaches attempt to reverse.
Why the pattern is hard to measure
Dietary research was built around meals. Recall instruments ask what was eaten at breakfast, lunch and dinner, and grazing fits that frame poorly.
Consumption that is not remembered as an eating occasion is systematically underreported, which means national intake figures likely understate the contribution of unstructured eating.
This is one reason newer research favors photographic logging and continuous monitoring. The instrument has to match the behavior, and the behavior stopped looking like meals.