This is the time of the year when good intentions about a healthy diet tend to disappear amid a seasonal culinary combination of chocolates, roast turkey and vegetables, chocolates, Christmas pudding, and yet more chocolates.

Anna Middleton will also be having plenty of chocolate over the festive season, and will be enjoying a Christmas lunch.

However, she won't be feeling any guilt, nor will she be counting calories in the new year.

For 35-year-old Anna makes a type of chocolate that is actually good for you – raw chocolate.

The Bristol-based nutritionist is an expert on preparing raw food, and has even been teaching people how to make a healthy Christmas meal.

"When food is heated above a certain temperature, it starts to alter the proteins and fats, and it can diminish the vitamins and minerals that are there when it is raw," she explains.

When Anna starts to show me the sort of things she makes, it becomes clear that raw food doesn't have to be rabbit food.

There is a range of raw chocolates, which are available plain or in flavours such as fruit and nut, and truffle, and there are cakes made of raw chocolate and orange.

Small boxed sets of four soft-centre truffles cost £3, boxed sets of two plain, two fruit and nut, and two coconut chocolates cost £5, and a bag of individual mini chocolate and orange cakes costs £2.50. A large version of the raw chocolate and orange torte cake is sold by the slice at Radford Mill Farm Shop in Picton Street, Montpelier, and at Zazu's Kitchen in Stokes Croft. Anna also makes a nine-inch £30 version of the cake.

"Usually chocolate is made of cacao beans that are roasted at a very high temperature – which damages many of the nutrients – and then sugar and milk get added," says Anna.

"With raw chocolate the beans are kept at a temperature of under 40 degrees. They are cold pressed to extract the cocoa butter and cacao powder, and I sweeten them with natural sugar syrup called yacon, which comes from a Peruvian root vegetable."

For anyone like me who can't get very excited about eating salads, this seems like a wonderful new way to indulge in healthy eating – a case of having your (raw) chocolate cake and eating it. However, Anna cautions: "Raw chocolate is healthier than normal chocolate, but isn't a replacement for green vegetables and salads. Also it's a stimulant, so you have to treat it with respect."

Anna's talents are not confined to raw chocolate creations. The dishes she makes out of raw vegetables look like something from a top restaurant.

She regularly holds workshops on preparing raw food, and has recently been demonstrating how to create a raw Christmas lunch featuring sage and onion pate; red cabbage with apple; carrot and mint ribbons; stuffed peppers; and Christmas pudding – plus Christmas Mojito cocktails, both with and without rum.

But how can she make things such as a tart base without putting it in the oven? "I made it with oats mixed with coconut oil," Anna explains. "Other foods that are usually cooked can be prepared by marinating instead."

Anna first became interested in the effects of foods when she spent three years travelling and studying in South East Asia, India, Nepal and New Zealand.

She moved to Bristol after returning from her travels, and enrolled on a three-year practitioner course in holistic nutrition. She then discovered the benefits of eating raw food when she attended a talk at the Vegan Fayre.

"During the talk, they made raw chocolate. It was the first time I'd ever tasted raw chocolate and I found it amazing. I felt incredibly creative afterwards and wanted to draw," says Anna, who is now a support tutor at The Nutritional Healing Foundation.

"Raw chocolate has lots of antioxidants and minerals. It is a superfood like nuts, seeds, vegetables, seaweed, and sprouts, and can improve how you feel physically, mentally and emotionally."

Anna holds regular workshops and one-to-one consultations at her home in St Paul's, and also hosts 'raw pot luck' gatherings at which people bring along raw and vegan food dishes to share. I love food and having people round for something to eat," she says.

"Raw food has all sorts of health benefits. I want to make it possible for people to give it a try by teaching recipes that aren't complicated, and don't require fancy kitchen equipment."

Anna emphasises that there is no need for people to follow a completely raw food diet to discover the benefits.

"It's not about being 100 per cent anything. So many people think that if they're going to embark upon a particular type of diet, they have to go for it full steam, but even having a bit more salad is healthy.

"Increasing the amount of living food in our diets can simply mean having a smoothie or juice in the morning, and eating more salad with meals."

● Anna Middleton will be running a number of workshops in 2010, including Introduction to Living Foods on Saturday, January 23, and Introduction to Raw Chocolate on Sunday, January 24. For further information, go to www.annamiddleton.com.