'I'm not at home that often. I spend a lot of my time in San Diego - I do costume design for their opera - so when I'm in London, I like to invite everyone round and cook for them.

My most memorable party was probably after the opening of the Fashion and Textile Museum. I invited 30 American guests to my flat and did a huge salmon. It was a fabulous night, sitting among the camellia trees on my balcony. I find fish easy to cook and prepare. You can do a dinner party for 20 people in 20 minutes, and then eat the leftovers cold the next day. I usually buy a whole salmon as I have a fish kettle. I add white wine, some onions and fennel, and then serve it whole on a long dish with mayonnaise, slices of lemon and basmati rice. For pudding I'll serve rhubarb crumble - which I make with fresh ginger - and double cream, washed down with white wine. I only really drink at parties; normally I stick to mineral water.

I do most of my shopping at Borough Market, everything else I buy at supermarkets that are open late like Sainsbury's in Nine Elms. It's only by accident that I'm health-conscious - it's what I like. Organic is better, especially with things like strawberries as they absorb all the poisons. Sesame salt is another absolute must. I buy fresh sesame seeds, toast them, and then grind them up in a pestle and mortar. It's nice to sprinkle on food instead of salt.

Eating in San Diego isn't that much different from eating here. For breakfast I'll have porridge with soya milk and fruit, sprinkled with some ground cinnamon. I try to avoid too many wheat products - I managed to lose weight when I cut them out entirely. Lunch I'll make myself - usually some cold rice and salad with a dressing of olive oil, mustard, caraway seeds and garlic, or tabbouleh. I'll put it in a little self-sealed box and take it into work. We should be opening a café in the museum soon, serving healthy food. It's a fashion museum, after all.'

· The Fashion and Textile Museum, 83 Bermondsey Street, London SE1 (020 7403 0222)

Sparkling mineral water

Nutritional purists may claim that still mineral water is a better option than sparkling but I think the advantages are likely to be relatively marginal compared to the benefits of drinking any form of mineral water over tap water.

Basmati rice

While we've been encouraged to have our fill of starchy carbs such as this, there is good evidence that too much of this stuff can pile on the pounds and increase the risk of diabetes too. There is room for carbohydrates in the diet, but not in the amount generally advocated by the dietetic establishment. Zandra seems to exercise moderation in her intake of carbs, and I think we have much to learn from her in this respect.

Rhubarb

Rhubarb is a notoriously fibrous vegetable, which also contains mild laxative components known as anthraquinones. Frequent consumption will help keep Zandra regular.

Fennel

Apart from the general nutritional benefits to be had from any vegetable matter, fennel also seems to be good for the gut, and is believed to stimulate digestive function. Another nice pick.

Double cream

Conventional dietetic wisdom dictates that cream should be off the menu, on account of its considerable content of saturated fat and cholesterol. However, despite its artery-clogging reputation, I have yet to see any convincing evidence that saturated fat and cholesterol in the diet cause heart disease. I think some double cream sits quite comfortably atop Zandra's beautifully balanced basket.

Whole fresh salmon

This fish is rich in the so-called omega-3 fats that are believed to protect against a range of afflictions including heart disease, breast cancer, depression and dementia. A couple of portions of salmon each week should go a long way towards helping keep Zandra in the pink.

Fresh ginger

Ginger has blood-thinning properties that may help prevent circulatory conditions such as heart disease and stroke. However, in natural medicine, ginger is also used to treat a wide spectrum of everyday ills including indigestion, fever, nausea and travel sickness. As far as spices go, this is one of my hot favourites.

Sesame salt

Sesame seeds are rich in disease-protective antioxidant substances and also contain health-giving minerals including magnesium and potassium. Used as a condiment, sesame seeds are unlikely to have significant effects on health. However, as an alternative to salt, I reckon Zandra's homespun concoction is pretty tasty.

Lemons

Apart from a hefty dose of vitamin C, lemons also offer a substance called limonene which is believed to have anti-cancer properties. Zandra's basket contents make perfect sense from a nutritional perspective.

Onions

Onions have a lot of goodness to offer. They are rich in a flavonoid compound known as quercetin believed to reduce the risk of heart disease. Onions also harbour sulphur-containing compounds that may help in the deactivation of cancer-inducing substances.

Caraway seeds

Caraway seeds are believed to stimulate digestion and reduce the risk of discomfort after meals. They are also rich in limonene - the substance in lemons believed to help ward off cancer. All in all, a top seed.