Susan Greenfield, neuroscientist

I take Calcium, Omega 3 and a combination Vitamin C and B. The calcium is due to having cut down on dairy products and the Omega 3 is similarly to supplement a low fat diet as well as contributing towards a healthy cardiovascular system. The combination vitamin C and B I have been taking a long time on the Nobel prizewinner, Professor Linus Pauling's widely publicised advice, that it helps keep colds at bay.

Chris Steele, GP and TV doctor

I take Pharmaton capsules twice a day as they appear to be the only multivitamin preparation clinically proven to combat fatigue and tiredness. I also take a capsule of high-dose fish oil once a day (Morepa or Seven Seas cod liver oil) for their cardio-protective effect and positive effects upon joints.

Lowri Turner, journalist

I take Udo's oil capsules as well as using the oil on my salads. It not only helps my skin, which is dry, it also helps my mood. Udo's oil is a mix of fish oils, flax, linseed etc and so is especially brilliant at balancing hormone levels especially. It is also odourless. The only downside is that it is really expensive. It was recommended by the personal trainer I went to after the birth of my first child when I was totally knackered. Why spend money on moisturisers when you can moisturise from the inside?

Alain de Botton, philosopher

Whenever I feel I may be catching something, I reach for my Boots vitamin C tablets. I know rationally that they don't help at all, but they give me an illusion of having "done something" to combat an impending illness and hence serve some purpose. In general, though, I'm a believer that modern diets are actually on the whole OK at providing you with everything you need; and that feeling not that well some of the time is just part of being alive.

Tracy Edwards, yachtswoman

I take Pharmaton - based, to some extent, on the strength of its advertising campaign. I work 16 to 20 hours a day at the moment, seven days a week and think the only reason I'm still actually standing, breathing and sane is because I'm taking it. I do notice a lack of energy if I don't take it but it's difficult to pin down if that is psychological or physiological. I also take vitamin C, in the form of Berocca, and cod liver oil as a leftover from my sailing days. The food we ate on the boat was horrible freeze-dried stuff and we were advised by nutritionists to start building up our vitamin intake six months before. By the time we finished, though, we were all still fit and healthy so it must have worked.

Ruth Rogers, chef

Friends in New York swear by their supplements. I'll go to their cupboards in search of something delicious to eat and find rows and rows of jars instead. So every once in a while I decide, right, this is what I should be doing, in that self-improving American sort of way, and spend tons of money in a health food shop on vitamin this and vitamin that. I'm full of noble intentions, but the pills are so big, so hard to swallow and smell so awful that I end up looking at them in the bottom of my bag for a while and then giving up. Maybe I will regret it but I seem pretty healthy and I think a good diet should be enough.

Zoe Williams, journalist

I don't really take anything. Unless you count a lot of nicotine. I find that it aids concentration and street credibility. I take it in cigarette form, but I believe you can get patches.