Saskia asks: Why do fatty foods taste so yummy?
Wynnie says: People often find low-fat or fat-free versions of their favourite foods are disappointing imitations of the original, despite what the label promises. This is not psychological: removing fat from food usually changes its texture, aroma and taste.
For years, scientists have thought that fat doesn't have any taste at all but merely acts as a carrier for flavours. Researchers have argued hat there are only four basic food tastes, sour, sweet, salty and bitter, with an additional umami or savoury taste found in protein-rich foods such as cheese and meat.
But a team of French scientists disputes this theory. They have discovered that mice have a taste bud that responds to fat. As soon as mice taste fat, they release fat-digesting enzymes and increase the absorption of fat from their gut. Mice that have had their fat sensors modified show no preference for fat at all.
The researchers suggest that humans, whose sense of taste works in almost exactly the same way as that of mice, almost certainly have the same taste bud. They argue that, from an evolutionary point of view, having taste buds that sense fat is a big plus, because it makes animals crave and eat fatty, energy-dense foods which can be stored away and utilised in times of need.
Although fatty foods do taste good, we should eat only moderate amounts - they shouldn't be banned from your diet altogether.
And low-fat foods aren't always a good alternative to the real thing. Recent research from Cornell University in the US showed that people eat an average of 28 per cent more calories when they choose low-fat snacks over regular ones. People often feel less guilty about eating low-fat foods, so they tend to overindulge, even if they don't like the taste as much as that of the regular versions.