The barrage of information on links between diet and disease has left most people feeling they need a PhD in biochemistry to understand it, let alone know how to interpret it on the dinner plate. But now one woman has come up with a beautifully simple healthy-eating code based on the colour of food.

Jane Sen, dietary adviser and head chef at the Bristol Cancer Help Centre, who won a BBC healthy cooking award yesterday, says that nature has done all the hard work for us. Antioxidants, those valiant nutrients which combat cancer cells, are also very often what gives a fruit or vegetable its colour. Based on research from around the world as well as advice from specialist doctors, Sen has come up with a simple rule: we should all make sure we are eating as many colours as possible every day.

"If there's a colour missing, very likely it's an antioxidant. You actually need all the antioxidants all the time, so the simple solution is to make sure your fruit bowl and vegetable basket have all the colours in them: orange, red, purple, bright green, curly green and yellow. This is not just for when you are ill, but also to protect against ageing, promote fitness and guard against illness."

She warns against simply consuming vast quantities of whatever happens to be the week's wonder fruit. "People get an idea that because they've had betacarotene in carrots that's OK. But that's only one of 40 carotenoids, and you need all of them. I've been thinking about making a full list of which foods contain which antioxidants, but I'm trying to keep this about food, not research chemistry. You need antioxidants all the time and they need each other to work properly. Research shows that when they are in the body, they can be dangerous unless they continue to work with other antioxidants.

"Following the colour key stops this becoming a scientific minefield and vastly improves your diet. Eating as many raw fruits and vegetables as possible - preferably scrubbed rather than peeled - also helps enormously as you then get the full hit of antioxidants." That said, if someone is either suffering from cancer or is known to be predisposed to the disease, it is worth knowing which foods have particularly useful antioxidants in them. Lycopene - shown by research to be good at the prevention of and recovery from prostate, bladder, cervical and pancreatic cancer - can, for example be found in various pinky-red foods such as pink grapefruit, crab shell, watermelon and tomatoes.

Sen's work in Bristol, which revolves round a vegan, low-fat, salt and sugar diet based on the colour theory, has been recognised by heart disease charities for its contribution to healthy eating and has inspired many cancer patients who have visited the centre. She believes it can help all aspects of health, even conception.

Sen has not always been in healthcare, having worked as a chef for many years for various royals as well as healthy-eating rock stars such as Peter Gabriel. "I wanted to feed people who were hungry at a different level, so I studied nutrition and now scour science journals and the internet for the latest research to use at Bristol.

"I aim to provide a bridge between all that information and the dinner table by making the research accessible and explaining how to turn it into delicious food. Healthy food can be a delight to eat and doesn't have to taste like a cardboard box. Hippocrates' famous statement about 'food being medicine' is inspiring only when everything to do with it doesn't feel or taste like medicine."

• For more information, the Bristol Cancer Help Centre helpline is 0117-980 9505. Its website is www.bristolcancerhelp.org. Jane Sen's cookery book, Healing Foods Cook Book, is available from the centre for £12.99.