A five year study has just been published in The New England Journal of Medicine (February 2013) using 7447 volunteers aged 55 – 80 at high risk of cardiovascular disease, but with no symptoms. These volunteers were divided into 3 groups. The control group was put on a low fat diet (as per American Heart Association guidelines), and the two intervention groups were put on Mediterranean diets, rich in fresh fruit and veg, seafood, whole grains, monounsaturated fats and very low in meat and dairy. There were no calorie restrictions for any of the volunteers who were monitored regularly. The diet of the first intervention group was supplemented with 30 g of nuts (15g walnuts, 7.5 g almonds and 7.5g hazelnuts) a day; and the second with 50 ml of virgin olive oil a day. Compliance with the nut and olive oil prescriptions was also tested via analysis of urine and blood.
An interesting finding was that the intervention groups consumed more calories than the control group.
The results of this study were so dramatic that the trial was stopped ahead of time, as the control group was clearly at such a disadvantage. The risk of stroke in particular, reduced significantly (49%) in the two Mediterranean-diet groups, while their overall risk for heart disease was reduced by 30%. These 2 groups of volunteers also had lower blood pressure and a better blood glucose and blood lipid profile than the control group.
While the control group consumed less fat and fewer calories, this did not appear to do much for their cardiovascular health.
The results of this study show that it is healthy to have a diet high in fat as long as it comes from unrefined plant sources, as opposed to saturated fat from animal sources. Thus it is the type, not the level of fat, that counts for heart health.
This study also provides clear evidence to show the connection between nuts, extra virgin olive oil and reduced risk of cardiovascular disease, not only because of the monounsaturated, healthy fat they contain, but also because of the polyphenols (anti-oxidants) nuts and extra virgin olive oil both contain.
In conclusion, an energy unrestricted Mediterranean diet, supplemented with extra virgin olive oil or nuts, resulted in substantial reduction in the risk of major cardiovascular events among high-risk persons.
More focus should be given to overall dietary patterns rather than the health benefits of isolated nutrients.
The results of this study strongly support the benefits of the Mediterranean diet for the primary prevention of cardiovascular disease.
HEALTH INSIGHT
MARCH 2017