Despite being oily, salmon can actually help burn off calories from the rest of your Christmas meal. This is because it is rich in essential fatty acids (EFAs) as well as another fat called DHA. At high levels, these increase metabolic rate and fat burn-off. EFAs have other benefits, too. Numerous studies have found that they can aid fertility, help to stave off Alzheimer's disease, and improve skin conditions such as eczema. And then there's the effect of oily fish on your cardiovascular health. A trial in the States found that people who ate two servings of oil-rich fish every week had a 40 per cent lower risk of heart attack. Another study, by the Harvard School of Public Health, found that women who ate five servings of such fish every week were 66 per cent less likely to suffer a stroke.
TURKEY, DUCK & GOOSE
Turkey is low-fat, so is less likely to add pounds than the usual Sunday roast. "Its high-protein content helps your body to build not just muscle, but the enzymes needed to burn off fat and help the body detoxify," says the London-based nutritionist Amanda Wakeford. And that's not to mention its beneficial effect on mood. Turkey is one of the richest dietary sources of tryptophan, a protein needed to make the mood-boosting brain chemical called serotonin. Researchers at the University of Maastricht found that low levels of tryptophan were associated with low mood and forgetfulness, while higher levels are found in those who are happier and more mentally alert.
Goose and duck contain more fat than turkey, but this has benefits, too. Mary Enig, an American biochemist and nutritionist, points out that duck and goose fat contains palmitoleic acid, an antimicrobial substance that helps you to fight off winter bugs. Both meats are also an excellent source of zinc, needed for fertility and immunity; iron, needed to oxygenate the blood; and B vitamins, needed to convert food into energy.
An after-dinner helping of cheese is exactly what your teeth need for protection against tooth decay. "All high-protein foods lower acidity levels in the mouth, in which oral bacterial thrive," says Maria Rodriguez, Professor of Dentistry at the University of Madrid, who has researched the effect of food on teeth. "Cheese also helps tooth mineralisation by raising calcium levels in enamel, the hard outer surface of teeth." This helps to further fortify teeth against corrosive acids formed in the mouth when you eat carbohydrates such as bread, sweets or potatoes.
Cream - anything associated with high cholesterol - helps skin stay supple, boosts mental clarity and keeps bones strong. Cholesterol is only harmful when levels of LDL or "bad" cholesterol exceed HDL or "good" cholesterol. This fatty substancehelps to transport vitamins into cells, and is needed to make vitamin D. The sex hormones oestrogen, testosterone and progesterone are synthesised from it. Patrick Holford, nutritionist and founder of the Institute for Optimum Nutrition, says: "Cholesterol may play a role in thought, awareness, co-ordination, cognition and mood."
CHRISTMAS PUDDING & MINCE PIES
Ignore the sugar they contain; their main ingredient is fruit-mince - a mix of dried fruit such as raisins, apple and apricot - which provides a concentrated source of antioxidants. The spices in mince pies, such as cinnamon, have been shown to soothe digestion, help regulate blood sugar and reduce stomach acidity.
Take comfort in those fatty calories. Mary Enig, the author of Eat Fat, Lose Fat (Hudson Street Press), says that the fats found in butter have antitumour and immune-system supporting properties. "Lauric acid helps the body combat disease in many ways, and it's only found in butter and coconut oil. Another substance, 4C butyric acid, has antifungal properties and anti-tumour effects and is unique to butter." Butter is also the only source of "Wulzen factor" - an anti-stiffness compound.
Chocolate boosts mood, activity levels and sex drive - but it has to be dark and full of cocoa. "Theobromine and phenethylamine in cocoa stimulate dopamine production in the brain and are powerful mood stimulators," says Patrick Holford, nutritionist and the author of Natural Highs (Piatkus, £14.99). "Recent studies show that dopamine kick-starts a brain chemical called DARP-32. This activates hormones that make women more interested in sex." However, he warns against eating cheaper chocolate brands, which are highly sweetened and don't contain enough cocoa to benefit.
CHAMPAGNE, WINE & CIDER
Until now, red wine had stolen all the glory for protecting arteries and the heart. But no longer; scientists have discovered that champagne is also rich in antioxidant grape compounds that prevent the stiffening of artery walls. That's not all; although they can't explain why, an American study recently discovered that people who drink mostly champagne have a greater lung capacity than those who drink mainly red wine. And British researchers analysing the components of cider have discovered it might be as good for you as a cup of green tea. Scrumpy is a startlingly rich source of vitamins C and E and beta-carotene, all of which protect the body from age-related degeneration. Red wine and port keep your arteries clear and could protect you from cancer. Rich in flavonoids that protect blood vessels and the heart, red wine also contains an anti-fungal compound that is converted in the body into a powerful cancer-fighting agent.
Caffeine can protect against Parkinson's disease and reduce brain damage caused by strokes, especially if you drink it alongside wine. A study of 8,000 men by the Honolulu Heart Program found that the risk of developing Parkinson's was lowest in those who drank the most coffee. A study carried out on rats found that if coffee is consumed soon after wine it can shield brain tissue from the effects of a stroke.
A pint of Guinness might stop you from going blind, contains the vitamin B equivalent of several helpings of green vegetables and could enhance your sex life. Researchers in Canada and the US have found that beer, especially darker ales and stouts, may reduce the incidence of cataracts by as much as 50 per cent. This is because ales are a rich source of antioxidants that appear to protect the eyes against age-related damage.
Dark beers contain high levels of the B vitamin folate - also found in green, leafy vegetables - which lowers levels of homocysteine, a compound linked to arterial clogging -a main cause of erectile dysfunction.
A good bout of lazing this Christmas will help your body to repair tissues, rebuild immunity and boost memory. According to Professor Peter Axt, a health researcher from Fulda, Germany, a few hours of lazing each day could even be better than exercise if you want to prolong your lifespan. "People who would rather laze on a couch instead of running a marathon, or who take a midday nap instead of playing squash, have a better chance of living to old age," Axt says in his paper "On the Joy of Laziness".
He cites research that found that people who run long distances into their fifties are using up energy they need for other purposes and are more likely to suffer memory loss. "Strenuous exercise strains your body and can make you more vulnerable to illness," says the professor.
Axt's argument is backed by US research showing that stress can decrease immunity by up to 40 per cent and lead to irritable bowel syndrom and migraine.
Bingeing your way through a Christmas feast might leave you bloated and unable to move, but look on the bright side - it can help to set back the clock. Researchers in Finland have confirmed that the post-bingeing state of sluggishness and lethargy induces a surge of endorphins and human growth hormone (HGH), which are responsible for cell regrowth and repair. The increase in HGH can be so great that it encourages rejuvenation in tissues that would otherwise not be in renewal.
SINGING YOUR OWN PRAISES
Don't feel guilty about pigging out. "Research has found that people who are prone to guilt and self-deprecation are more prone to colds and flu, cold sores, backache, anxiety and depression," says Caroline Meyer, a life coach based in London.
"Conversely, people who 'talk themselves up,' reminding themselves how lovable, beautiful or successful they are, have stronger immunity and rarely suffer problems related to anxiety or depression."
For those suffering from guilt or depression this Christmas, Meyer suggests standing in front of the mirror each morning saying: "I love you," or other complimentary phrases, to your reflection. As your self-image inflates, so will your mood and immunity.Reuse content