A different goal (satiety), a strikingly similar food list.
Volumetrics is built on a genuinely interesting insight from satiety research: foods with high water and fibre content fill you up on fewer calories than energy-dense foods like fried snacks or sugary drinks — so eating more (in volume) of the right foods can support weight management without constant hunger.
| Dimension | Volumetrics | THE FAD |
|---|---|---|
| Core rule | Choose foods with low energy density (fewer calories per gram) — mostly water- and fibre-rich foods — to feel full on fewer calories | No energy density calculation — scores food quality signals directly |
| Developed by | Barbara Rolls, PhD, a nutrition researcher at Penn State, based on satiety research | N/A |
| Overlap | Vegetables, fruit, broth-based soups and lean proteins are staples — high overlap with THE FAD's Food signal | Rewards the same categories, for inflammatory-load reasons rather than satiety reasons |
Volumetrics is fundamentally a satiety and weight-management framework, not an inflammation framework — but its recommended foods (vegetables, fruit, legumes, broth-based soups, lean protein) heavily overlap with what scores well on THE FAD, because low energy density and low inflammatory load tend to correlate in whole, unprocessed foods.
A food could theoretically be low energy density and still fairly inflammatory (some diet sodas or artificially bulked-up processed foods), so the two frameworks aren't identical — but in practice, most Volumetrics-friendly meals would also score reasonably well on THE FAD.
The best way to understand the difference is to see what a real day scores.
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