A.  Following two major operations for heart disease, Bill Clinton, a devotee of burgers, fries and doughnuts, turned to a low fat, plant-based diet on the advice of Dr Dean Ornish, author of books including Eat More, Weigh Less (Quill, £10.71 - buy here), and other experts. Clinton has lost over 20 pounds so far.

Dr Ornish recommends a lifestyle programme centred on diet with regular moderate exercise (at least 30 minutes daily), stress management (yoga and meditation) and, crucially, not smoking.  Research suggests this regimen can help prevent heart disease, and even reverse it without the need for drugs.

The diet excludes dairy, meat, poultry and fish, as well as fats and oils. But Dr Ornish recommends taking 4 grams daily of fish oil (which obviously isn’t vegan) because the omega-3 essential fatty acids in fish have been shown to benefit heart disease.

The Ornish diet focuses on vegetables, fruits, whole grains, legumes and soy products, all unrefined.  However, he advises that to stay generally healthy and lose weight (as opposed to Clinton’s more extreme situation), you can eat other foods in moderation, including non-fat dairy products (skim milk, non-fat yogurt, cheese and sour cream) and egg whites.

Avoid or cut down on these foods:  meat of all kinds; oils and oil-containing products, e.g. margarine and most salad dressings; avocados, olives, nuts and seeds; all sugars (except in fruit), alcohol and commercially prepared foods with more than two grams of fat per serving.

Eat several little meals: because this diet makes you feel hungry more often.

Don’t punish yourself:  if you indulge one day, eat more healthily the next – ditto with exercise, says Dr Ornish’s Preventive Medicine Research Institute - for more details, click here.

There can be downsides: eating lots of plants is undoubtedly good for you but excluding so many foods may lead to nutritional deficiencies, including vitamins B2, B12 and D, iron, zinc, calcium, iodine, essential fatty acids, protein and retinol (the animal form of vitamin A, which is essential for vision, skin health and bone growth). So if you’re contemplating a vegan diet, you need to plan meals carefully and perhaps consider supplementation.

 

THE TRUTH ABOUT...  WATER

Water makes up about two thirds of our bodies.  Every bodily system depends on it.  We lose water constantly, even by breathing, so we need to replenish daily by drinking liquids, plus eating foods that are high in water, e.g. fruit.

The amount you need varies.  It depends on your size, the climate and how active you are.  Pregnant and breastfeeding women need lots.  So do children.  The best yardstick is to drink enough so that you don’t feel at all thirsty and you pee pale yellow.

You can get ill by not drinking enough.  Dehydration leads to lots of problems including headaches, constipation and lowered mental and physical functioning.  In athletes, just two per cent dehydration brings overall performance down 20 per cent.

Sipping still water is best.  It’s natural, thirst-quenching, cheap and has useful minerals. Tap water is fine.  Herbal teas are good too.  Drinking lots of caffeinated drinks is dehydrating, as is alcohol, so match them with equal amounts of water.

By Zoe Harcombe, nutritionist and obesity expert, www.zoeharcombe.com

 

CHAPTERS THAT CHEER

I love The Happiness Project by Gretchen Rubin (Harper Collins, £9.99 - buy here), which is an account of the year she spent test-driving ways to be happier.  The New York wife and mother of two was on a city bus watching the rain drip down the windows when she realized, ‘Time’s passing and I’m not focusing enough on the things that really matter.’  For October, she delves into mindfulness, gives up on meditating and keeping a food diary, ponders competitiveness and self-doubt (when friends get successful) and visits a hypnotherapist.  Oh, and keeps her temper more often.  Compulsive reading.