Blue bowls, a sad Chopin waltz and clover-shaped snacks: none of them changed how food tasted to people who had lost their sense of smell. What they reach for at home is chilli, cumin and crunch

Most of what we call the taste of food is smell. The tongue handles sweet, salty, sour and bitter; nearly everything else, the difference between a strawberry and a raspberry, arrives through the nose from the back of the mouth. People who lose their sense of smell often describe the same thing: food turns into texture and temperature, and eating becomes a chore. Some lose weight because they stop caring about meals. Others gain it, possibly by eating more in search of the pleasure that has gone missing.

Meanwhile, a separate line of research has spent twenty years showing that flavour can be nudged from outside the mouth. In a well-known Oxford experiment, potato crisps were judged crisper and fresher when the sound of the bite was played back louder through headphones. In another, popcorn was rated differently for sweetness and saltiness depending on the colour of the bowl it was eaten from. So a team led by Lorenzo Stafford at the University of Portsmouth, with co-authors from the charity SmellTaste and the University of East Anglia, asked an obvious question that nobody seems to have tested: could those tricks give something back to people who cannot smell? Their paper was published in PLOS One on 1 October 2026.

They recruited 33 adults who said they were living with smell loss, most of them reached through the university's website or the charity. The average age was about 64. Six traced the loss to COVID-19 and three to a head injury; eighteen did not know the cause, and three had been born without a sense of smell. A standard sniff test with a diluted alcohol called n-butanol confirmed the problem: the group's average score was 4.2 on a scale where students given the same test had averaged 10.

Each person then ate nine small portions. Oat biscuits came in a green, a blue and a yellow bowl. Cheese-flavoured savoury snacks came as circles, triangles and clover shapes, eaten blindfolded so the only clue was the feel of the shape. Tinned pineapple chunks were eaten, also blindfolded, during 45 seconds of headphone music chosen to be neutral (Holst's 'Neptune'), sad (a Chopin waltz nicknamed 'Farewell') or frightening (Liszt's first Mephisto Waltz). After each portion they marked on 100 mm lines how pleasant, sweet, salty, sour, bitter and intensely flavoured it was.

Nothing moved. The biscuits scored 59, 61 and 58 out of 100 for pleasantness in the green, blue and yellow bowls. The snack shapes scored 50, 51 and 46. The pineapple scored 62 with neutral music, 53 with the sad waltz and 59 with the Liszt, and although that nine-point dip looks like something, the scatter between people was far wider than the gap and it did not reach statistical significance. Nor did any difference in sweetness, saltiness or the other ratings once the analysis was corrected for the number of tests run. How much smell a person had left made no clear difference either.

The authors are candid about why this may say more about the experiment than about the idea. Only one food was used for each trick. There was no plain white bowl to compare the colours against. The two contrasting pieces of music were both gloomy, and they now think a cheerful one would have been the better test. Hearing was not checked, in a group whose average age was in the sixties, and taste on the tongue was not tested at all. Twenty-nine people were left in the analysis once the three born without smell and one outlier were set aside, which is few for the number of comparisons made. They call the study preliminary in its title, and it is.

The part worth keeping is a questionnaire the same people filled in about what they do at home. Twenty of the 33 said they add extra herbs and spices, naming cumin, paprika, chilli flakes and chilli most often. Eighteen said they lean on texture: crunchy things, fruit, salads. Far fewer used the tricks the lab had tested: seven put music on while eating and six paid attention to how the plate looked, with 'avoids beige dinners' among the examples recorded. Some also reported a preference for very salty or very sweet food, which is worth knowing about for other reasons. And two wrote that they eat because they need to, not because they want to.

Chilli makes sense. Its burn is not a smell or a taste but a signal carried by a different nerve, the trigeminal. A 2023 study at the Monell Chemical Senses Center in Philadelphia, also of 33 people with smell loss, found that adding capsaicin, the hot compound in chilli, to tomato soup made it seem both more flavourful and saltier. That hints at a way to keep food interesting without reaching for the salt shaker, though the effect on how much people liked the food varied from one food to another. For now the evidence for heat and crunch is mostly what people report doing, not what trials have proved. A sudden or unexplained loss of smell is a reason to see a doctor, not just to restock the spice rack.