A person with an "educated palate" would undoubtedly rather eat at a Michelin-starred restaurant than tuck into a hamburger. But, says the author of a new diet book, there is far more to taste than where you choose to dine. Published in the States earlier this year, The Flavour Point Diet, by Dr David Katz and Catherine Katz (Rodale, £9.99) has already sold 10,000 copies there, and, for "food faddicts" here, it is likely to have similar appeal. Like the popular Atkins diet, it doesn't require cutting out favourite foods - chocolate and meat feature - but unlike the low-carb diet, so do bread, rice and potatoes.
It works by categorising foods into flavour "themes" to retrain your taste buds and keep you satisfied, thereby helping to control weight. But it's not just about fat-loss - the diet also helps to stop high-sugar, high-salt, high-fat foods from seeming so appealing. Sounds great. But does it work?
Our sense of taste evolved to protect and nurture our bodies. Unsafe foods, such as poisonous plants or rotten meat, taste bad; an appetite for salt or sugar helps to regulate our carbohydrate and mineral levels; a desire for orange juice, for example, exists to get essential vitamins into our bodies; and a lust for fat stems from our bodies' need to store energy. However, one of the effects of the huge variety of highly processed and intensely flavoured dishes we eat, says Dr Katz, is that our taste buds are overstimulated. This leads to larger, more intense appetites, then weight gain as well as heart disease, diabetes and other diet-related illnesses.
There's no doubt that our taste buds adapt to what we eat. For example, if you regularly use chilli sauce, the nerve endings on your tongue become desensitised. Similarly, by adding salt to every meal, your palate becomes less attuned to its presence and you'll have to add more to get the same taste sensation. According to the Flavour Point Diet, however, you don't even need to give up chilli or salt to get your palate into working order. You simply have to recognise flavour categories and avoid eating too many different categories in one meal. "A jumble of flavour categories turns on too much appetite," says Dr Katz. "Research suggests that different categories - sweet, salty, savoury, sour, bitter - stimulate independent appetite responses. So, when these are combined, you turn on an excess of appetite, and need more calories to feel full."
Dr Katz does point out that it is important to differentiate between flavour categories and flavours: "Banana and chocolate are different flavours, but they're both in the same flavour category - sweet." His words will be music to a dieter's ears, and among the many dessert recipes in the book, they'll find banana-chocolate-chip soft-wheat muffins. Indeed, looking through the book, it's difficult to imagine that the following dishes could help you to slim: coconut Thai chicken, prawn pasta primavera, lemon salmon with cucumber dill sauce, piña colada frozen dessert...
But the diet seems to work. Dr Katz, a professor at Yale University's School of Public Health, has trialled it on 20 men and women, and after 12 weeks, each lost an average of 7.2kg (16lb). Better still, their cholesterol levels dropped by an average of 0.36 points, and blood pressure was also reduced.
The diet works by gradually introducing your body to flavour themes. For example, on each day in the first few weeks there's one flavour theme, so every meal or snack shares a common ingredient. On "tomato day", for example, you'd have tomato, basil and feta omelette and toast for breakfast; cherry tomatoes and hummus as a snack; tomato and black-bean salad with pitta for lunch; corn chips and salsa as a snack; pasta with marinara sauce and garlic bread for dinner. It's this repeated exposure to similar flavours that subdues and educates the appetite centre, says Dr Katz.
"Each dish has a maximum of two flavour categories in it, so you can combine curry, garlic and citrus because that's only savoury and sour," he explains, but warns that the two flavour categories that shouldn't be combined, as they are powerful appetite stimulators, are salty and sweet, a mix often found in breakfast cereals, processed sauces and ready meals.
The "high" that taste buds trigger when you eat a mix of flavour categories results in addiction much like any other. The Flavour Point Diet reduces your "need" for high stimulation of your taste buds. It's a detox for your palate, helping you to overcome the addiction and eat more healthily without denying yourself pleasure. Dr Katz makes his regime sound like child's play, and if Jamie Oliver managed to retrain the taste buds of recalcitrant school children, maybe it is simply a matter of education after all.
You've got it licked
Taste receptors on your tongue send a signal to your brain when specific taste molecules, such as sweet or salty, come into contact with them. Heat or warmth intensifies flavour, which is why melted ice cream tastes much sweeter than when it is very cold.
To see how flavour pairings can increase or decrease your desire for food or drink, try eating a green apple before drinking chardonnay. The sourness of the apple reduces your sensitivity to acidity, so the wine loses its bright flavour. As a general rule, sour and sweet flavours suppress each other, as do salty and sugary. Here are some examples of the different flavour categories, from the strongest appetite stimulators to the least strong:
Sweet eg bananas, honey
Salty eg olives, celery
Savoury eg sage, thyme
Sour eg lemons
Astringent eg tea, red wine, broccoli
Bitter eg coffee, beer, camomile tea