I can never have too many clementines, satsumas and oranges at this time of year. My body craves their uplifting cool juiciness. I’ve even started copying my parents and having half a grapefruit for breakfast, although I prefer the slightly sweeter pink variety. I find the yellow ones are a bit too acidic on an empty stomach.

Pink grapefruit is delicious grilled with soft brown sugar. If you have any star anise, you can crush up a couple with the sugar to add a slightly aniseed/liquorice flavour. Sprinkle the sugar over the top of the cut grapefruit and put it under a medium-hot grill for about five minutes, until the sugar caramelises and the grapefruit becomes tinged. Watch carefully, as the sugar can burn easily. This is yummy served with Greek-style natural yoghurt.

To some extent I think our bodies crave the thing they need — not an excuse for continuing to tuck into chocolates. January is commonly when we fall prey to colds and flu, so it’s important to ensure that we get enough of nutrients such as vitmain C that will help to minimise our chances of catching a virus. We also need plenty of vitamin C, aka ascorbic acid, because it influences the production of the protein collagen , which we need for healthy structure and the funtion of connective tissues such as skin.

It is also involved in the structure and function of blood vessels and in neurological function. This vitamin has antioxidant capabilities, protecting cells from damage which can lead to the development of heart disease, accelerate ageing and cause some cancers.

But this doesn’t mean you should rush out and buy a vitamin C supplement, An orange contains about 86mg of vitamin C per fruit, which is well over the EU’s recommended daily amount (RDA) of 60mg a day. We just don’t need 1,000 or 2,000mg of vitamin C. I know this is contrary to the supplement manufacturers’ claims, but you are throwing your money down the toilet, and I have seen cases in my practice of people suffering from IBS symptoms and mouth ulcers as a result of taking vitamin C supplements.

Smokers are the exception because cigarettes put the body under oxidative stress. They need about 2,000mg of vitamin C a day and as it’s hard to get this quantity from a normal diet, a supplement is a good idea.

Most citrus fruits — oranges, grapefruits, lemons — contain good amounts of vitamin C; just half a grapefruit a day gives us enough to cover our needs. But tangerines, satsumas, mandarins and clementines aren’t great at providing us with this antioxidant nutrient. Mandarins and satsumas are varieties of the small, sweet tangerine, and the very similar clementine is thought to be a hybrid between the tangerine and the sweet orange.

The vitamin C in limes is famed thanks to British sailors, who used to eat them to prevent the skin disease scurvy, earning them the nickname “limeys”. In fact, of all the citrus fruit, limes are one of the lowest in vitamin C: the juice from half a lime tots up to only 4mg of vitamin C.

Oranges and lemons are also good sources of pectin, a soluble fibre that has a cholesterol-lowering effect. Pink grapefruit is rich in beta-carotene, which can help to protect our bodies against heart disease and cancer. But like oranges and yellow grapefruit, you get the most benefit from eating some of the white pith. This is the part of citrus fruits that’s richest in the pectin and the bioflavonoid hersperidin, which, along with other flavonoids, provides one of the most exciting areas of anti-cancer nutritional research. So don’t peel them too carefully.

Jane Clarke answers your questions in Times2 on Mondays; e-mail Jane.Clarke@thetimes.co.uk and visit www.janeclarke.com. She cannot enter into personal correspondence

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