In Los Angeles, raw food is nothing new. The actress Demi Moore allegedly lost 1st five years ago when she started following what is essentially an uncooked vegan regimen. If you exist on uncooked vegetables, seaweed, fruits, nuts, seeds and little else, it is not surprising that excess pounds will fall away.

Its followers also say that switching to raw food makes you feel more energised. This may be true. Losing weight can give you a high, and weeding out sweets, cakes, biscuits, fast food and takeaways will smooth out your blood sugar levels, leaving you more energised throughout the day. However, a raw food regimen is not just another diet, it's a way of life that requires serious commitment to reap the health benefits, and the long-term implications need to be considered carefully.

Replacing nutrients

Cutting out meat, fish, eggs, dairy foods and cereal grains would result in the loss of many nutrients. My advice is first to master a healthy and nutritionally complete vegan diet before progressing to raw food. This means making sure that you get enough protein from nuts, seeds and pulses. For bone-strengthening calcium you need plenty of sesame seeds, almonds, figs and dark green vegetables. Soy beans are also a reasonable source.

For iron you can turn to watercress, spinach, cashew nuts, peanuts, dried figs and prunes. The large amounts of fruit and vegetables eaten mean that you will easily hit your “five a day” target (one portion is about 80g of fruit or veg: an apple or pear, for example, or a couple of tablespoons of veg such as broccoli or cauliflower), so you will be fine for vitamin C and E. For vitamin D, in the UK you need to ensure that you get enough sunlight in summer to build up your body's stores for the winter.

As for micronutrients such as zinc, selenium and vitamin B12, I would take a general, vegan-approved vitamin and mineral supplement, although this is probably frowned on by raw food purists.

Young and old

Susan Price, a spokeswoman for the British Dietetic Association, says that she has concerns over a raw food way of life being suitable for children, the elderly and for pregnant and breast-feeding women. Price, a specialist in gastroenterology, says the high fibre intake could exacerbate IBS.

The Vegan Society: www.vegansociety.com , 0121-523 1730 (www.amandaursell.com )

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