When I was growing up we didn't have supermarkets. Everything was seasonal. Spuds, wonderful dairy produce, but limited diet. My winters were tormented by the smell of cabbage. In Ireland it was obligatory to boil cabbage for three hours. The vitamins were thrown out with the water. I have made stock where I have carefully thrown away all the juice and just kept the over-cooked vegetables. My mother would certainly have been proud.

I start every day with strong decaf coffee, French country bread and a fried egg. I'd rather not have anything if I can't have the egg. If I'm working, I'll have water, bread and M&S's wonderful unpasteurised Canadian cheddar for lunch. I make my own ravioli. I roll it in a hand-turned machine. I love coffee but 20 years ago discovered I was allergic to the bloody caffeine. I used to drink about three cups and would be in a state of near-suicide.

Although I cook a lot, I can't make fish. I don't think any man can; it requires too much daring and attack. One of my favourite meals is spaghettini with tomato sauce, parmesan and red wine. In Italy they know how to serve a decent meal. My favourite restaurant is Le Logge in Siena - it looks like an apothecary shop. I recently discovered Esca in New York - the best fish restaurant I have ever been to. I've never seen so many varieties of fish.

I gave up meat 10 years ago. I was having lunch recently with Glenn Close and had sea bass garnished with pieces of red stuff which I thought were chopped-up red onions. It was only when I realised they were bacon that I began to feel ill. Chicken seems to be in everything. I have high hopes God is going to turn out to be a chicken. St Peter will ask people if they eat chicken, and if they say yes he'll reply, 'It's not the place for you'.

When I'm not working, I go out for lavish lunches with my friends, drink too much, and spend the afternoons trying to sober up. I have discovered the importance of water. It's amazing how much booze you can put away if you drink twice as much water.

I have a glass or two of red wine with dinner. I love big Italian red wines and New Zealand whites. Brandy is my tipple: I can't keep the stuff in the house, because I would drink it by the gallon. My biggest sin is chocolates from L'Artisan du Chocolat, in London. You have to get a second mortgage in order to buy a small box of chocolates. I don't worry about my health. In response to a scare about butter I remember John Mortimer saying, 'Am I really going to give this up for an extra two weeks in the old folk's home in Lyme Regis?' That is the rule I live by.

Chocolate

Cocoa is rich in nutritional goodies such as magnesium and polyphenols that have benefits for the heart. Dark chocolate is best for its higher cocoa and lower sugar ontent.

Decaf coffee

People who are exquisitelysensitive are best off opting for decaf brews and should choose coffee beans that have been decaffeinated using either carbon dioxide or water-based processes, as these avoid the use of solvents.

Spaghettini with tomato sauce

Tomatoes are especially rich in lycopene which has been linked with a reduced risk of heart disease and prostate cancer. Lycopene is more readily absorbed when combined with oil, so a sauce is ideal.

Cheddar

Dairy products are quite common instigators of food sensitivity-related reactions which include a blocked nose, sinus congestion and catarrh. Unpasturised dairy products or goats' cheese are often less of a problem.

Red and white wine

It seems John drinks enough wine to increase his risk of a range of health issues including liver damage, heart rhythm irregularities and stomach ulcers. However his water intake helps.

Country bread

The main ingredient in French bread is white fl our, which has very little nutritional value. John should switch to whole rye bread.

Fried egg

The most predominant fat in eggs is monounsaturated - a type of fat that is believed to help protect against heart disease. For most people, an egg a day will not increase the risk of heart disease.

Ravioli

Pasta, which contains little more than refined wheat flour, is actually a quite un-nutritious food, and is therefore not a particularly healthy basis for a meal.

Water

Drinking water can help general well-being and is associated with a reduced risk of heart disease and some cancers. Drinking water with alcohol helps protect the body from toxic effects of alcohol.

Fish

Eating fish gives relative protection from heart disease, depression and dementia. Good sources of the health-giving omega-3 fats include salmon, trout, mackerel, herring and sardine.

· John Banville's The Sea won the Booker Prize (Picador, £16.99)