Can high diet quality reduce the incidence of cardiovascular disease?

This article investigated the relationship between diet quality and the incidence of cardiovascular events.

It is well established that particular dietary patterns and healthy life style can prevent the development of different cardiovascular diseases. There is strong evidence that diets with high intake levels of vegetables, legumes, fruits, nuts, whole-grain products,  mono-unsaturated fats (from olive oil) and poly-unsaturated fats (from walnuts, tuna and soybeans) offer protection against heart disease and stroke. The present study investigated the relationship between the quality of diet patterns and cardiovascular disease by determining the reduction in cardiovascular risk among participants following a pre-defined diet. 

The present study included 6,940 middle aged women (10,186) and men (6,940) from Sweden. The recommended diet included six dietary components in defined amounts: fats, sugars, fish, dietary fiber, fruit and vegetables. The diet quality of participants was ranked based on how well they followed the recommendations and was defined as low, medium or high. During a mean follow-up period of 14 years, the dietary history data of the participants was recorded by questionnaires and interviews. Cardiovascular events such as heart attack, stroke or death from a heart disease were reported.  

Results showed that compared to a low diet quality, high diet quality was associated with decreased risk of cardiovascular events. 1,093 cardiovascular events occurred among men and 703 in women. Adherence to a high quality diet was associated with a 27% reduction in the risk of cardiovascular events in women and a 32% risk reduction in men.  

When each dietary component was examined separately, there was little or no association with cardiovascular risk. Interestingly, no relationship was found between recommended levels of saturated fat (found in cheese, butter and sausages and generally considered to be unhealthy) and the risk of incident cardiovascular events. 

Overall, high quality diet reduced the risk of cardiovascular events. This study established the importance of considering a combination, rather than separation, of dietary components when evaluating diet-disease association.

Few participants fully adhered to the recommended amounts of diet components, therefore the results may be deflated. For instance, only 2% of subjects adhered to the recommended intake for saturated fats, and only 20 – 30% of subjects adhered to the recommended intake for fiber.