Recent times have seen growing enthusiasm for the health-giving properties of the Mediterranean diet. Based on natural, nutritious foods such as olive oil, fruit, vegetables, fish and beans (laced with more than a smattering of garlic and downed with a glass or two of red wine), the customary cuisine of the Med has been said to account, at least in part, for the relative longevity of the inhabitants of this region.
Seeing as this edition of OFM has a distinctly Italian flavour, I thought I'd take a closer look at the nutritional qualities of the Mediterranean diet, and at the evidence for its much-fabled ability to ward off illness and extend our lives.
Olive oil is rich in oleic acid, a so-called 'mono-unsaturated' fat that is thought to help lower blood levels of low-density lipoprotein (LDL) cholesterol - the form of cholesterol believed to predispose to the furring-up of the body's arteries. Other components in olive oil, namely oleuropein and squalene, have the capacity to help protect cholesterol from chemical change in the body, known as oxidation. This is important because there is evidence that it is only once cholesterol is oxidised that it has the propensity to sediment out in our vessels. Another boon is that olive oil may have an ability to thin the blood, which should help prevent the formation of tiny blood clots that can trigger heart attacks and strokes.
Fruit and vegetables
Fruit and vegetables are rich in a range of nutrients such as vitamin C, beta-carotene and folic acid, all of which have been linked to a reduced risk of heart disease and several forms of cancer. Fruit and veg are also rich in phytochemicals, which have significant disease-protective effects. For instance, black grapes and citrus fruits contain resveratrol and hesperidin respectively, both of which are thought to help stave off heart disease.
One fruit that is almost ubiquitous in the Mediterranean diet is the tomato, which is rich in the phytochemical lycopene. Like olive oil, lycopene appears to have the ability to protect cholesterol from oxidation, and higher levels of this nutrient in the diet have been linked to considerable protection from heart disease. Other evidence points to lycopene having a role in warding off a variety of cancers including those of the stomach, colon, rectum, ovary and prostate.
The sardine, a staple in the Mediterranean diet, is rich in omega-3 fats, which help to thin the blood, reduce blood pressure, maintain a normal heart rhythm and raise levels of 'healthy' high-density lipoprotein (HDL) cholesterol. Studies suggest that consuming more omega-3 fats can bring significant reduction in the risk of heart disease and a heart-stopping killer known as sudden death.
High omega-3 consumption has also been linked to a reduced risk of conditions including arthritis, depression and Alzheimer's disease.
Pasta and bread
These foods are usually based on refined our, which tends not to offer much nutritionally and also has a propensity to cause rapid rises in levels of sugar in the bloodstream. This can lead to surges in the hormone insulin that predispose to weight gain and diabetes in the long term. In the typical Mediterranean diet, pasta is usually eaten as a starter but not as a main course, and sandwiches have little, if any, place in the diet.
Beans generally give a slow and steady release of sugar into the bloodstream, and their consumption has been linked to beneficial effects on the levels of cholesterol and other unhealthy blood fats known as triglycerides. Beans are also rich in folic acid, which is believed to have benefits for the heart.
Studies show that garlic has the ability to lower cholesterol levels, reduce blood pressure and thin the blood - all effects that might be expected to protect against heart attacks and strokes. One study estimated that just the blood pressure-reducing effects of garlic could lessen the risk of these conditions by more than a third.
Red wine is often said to be good for the heart, which some scientists believe may be due to its content of resveratrol. However, there is evidence that the apparent benefits come not from the drink per se, but from other factors common in red-wine drinkers, such as healthier eating habits, a reduced tendency to smoke and better psychological health.
In the past few years, various studies have been published on the health effects of the Mediterranean diet. In one, researchers assessed the effects of five foods (fish, raw vegetables, cooked vegetables, fruit and olive oil) on the health of men and women who had suffered a heart attack. Over the six-year period, those eating the most of these foods were half as likely to die compared with those eating the least.
In another trial, also in individuals with heart disease, the effects of eating a Mediterranean diet were compared with those of a standard 'healthy' diet over a period of a little over two years. Individuals eating the Mediterranean diet were much less likely to have further problems with their heart, and their overall risk of death was 70 per cent lower.
The evidence suggests that for those who eat a Mediterranean diet, the living really is easy.