The trouble with living on Exmoor is that fresh food doesn't get up here very much. We live two miles out of the village, and when there's a delivery, all the locals know to get there instantly. Until recently, we had our own hens and so our own eggs, but I can't eat eggs any more because of the cholesterol. After my heart attack, the doctor pretty much banned them. Since marrying my second wife Louise, there's been a much stricter regime at home. In 1998, I wrote a book called Fit For Life. Louise noticed that I never actually followed the advice I'd given in my book. But under her firm eye, I'm now having to. The most important part of my diet is a thing called apple cider vinegar, or Honeygar as it's known in health food shops. About 22 years ago, I had bad arthritis in my hands and one of my hips so I started taking this. It took about a year for the effects to kick in, but once they did, my arthritis disappeared.

Both Louise and I cook. Well, Louise cooks and I can rustle up something providing it's nothing more than baked beans or salad. I do a good salad with lettuce, peppers and avocado. I always start the day with cereal: Weetabix mixed with Sugar Puffs and fruit, usually a sliced banana. And I swear by an apple a day. If lunch is on, then we'll probably have baked beans and tomato or lentil soup, and Louise will stick in a load of fresh vegetables.

Supper is our biggest meal. Three times a week I have tinned tuna or sardines with granary bread, soaked in my personal salad dressing - 50 per cent olive oil, 50 per cent apple cider vinegar and some mixed herbs. And, much to Louise's disapproval, I like to have a dollop of mayonnaise as a finishing touch. Louise will make a big plate for me and a medium-sized plate for her. I can run it off, you see. I go for a big run every other day, usually about 16 miles. A couple of years ago I did my seven marathons in seven days. It was only four months after my heart attack and I nearly gave up in Singapore. I was in the ambulance and somebody brought in a mug of sweet tea and I suddenly felt better.

I used to have lots of tipples until Louise got hold of me. My favourite has always been Talisker malt whisky, which is funny as I ended up taking part in a trek arranged by them. That was wonderful as I was able to quaff Talisker and eat blue cheese and chocolate right under Louise's nose. I have to be careful with what I drink nowadays. Louise thinks even a moderate amount of red wine is too much. I disagree!

I've been exploring for over 30 years. Louise thinks I had a heart attack because I was always eating leftover sponsor food like Mars bars, but I think it was probably caused by what I ate on the trips.

These days, I am happiest when I'm at home eating cake. When Louise is in a good mood with me, she comes back with this fantastic walnut and coffee cake. But she has to hide it or it disappears in a day. Everything in moderation is something I can't possibly go by.

Salad with lettuce, red peppers and avocado

Plant matter like this will help preserve Ranulph's health. Avocado is rich in so-called mono-unsaturated fat, believed to stave off heart disease.

Tinned tuna

The heart-related benefits of oily fish seem to be linked to the omega-3 fats it contains. In this case, the tinned sardines Ranulph eats occasionally are better than tuna.

Coffee and walnut cake

This will cause blood-sugar levels to soar and increase the risk of health problems longterm. Ranulph's wife is right to be suspicious of this kind of sugary fare.

Sugar Puffs and Weetabix with banana

This starch-and-sugar mix will cause blood-sugar and insulin levels to peak. Unsweetened muesli would give a more tempered release of sugar into Ranulph's system and is more nutritious, too.

Red wine

It's believed that a moderate amount of alcohol is beneficial to health, but evidence suggests that the optimal amount to drink is almost none. Ranulph's wife has, I think, got the measure of alcohol.

Vegetable soup This is an ideal way to get nutritious food into the system in a readily digestible form. A hearty and healthy choice indeed. I've met quite a few people who swear by this as an arthritis aid. It's thought that its effects in this respect are related to its ability to balance pH levels in the body.

Apples Apples are rich in compounds called flavonoids, especially catechin, which combat free radicals. People with a high intake of cachetin seem less susceptible to heart disease.

Baked beans

Beans are highly nutritious, and are linked with reduced risk of heart disease. The sugar and salt in the sauce are best avoided, but on the whole this is a decent fast food.