Researchers have known that variants in a stretch of DNA on chromosome 21 confer an increased risk of developing cardiovascular disease and having a heart attack, but how such variants interact with the environment and the role that such interactions play in the development of heart disease have been unknown. Now, new findings suggest that a diet that includes generous amounts of raw fruits and vegetables may reduce that inherited risk. This finding is published online today in PLoS Medicine.
In the new work, an international team led by Canadian researchers from McGill University and McMaster University sequenced bits of the DNA of 8114 participants in the global multiethnic INTERHEART study (3820 who had experienced a nonfatal heart attack and 4294 controls). Specifically, they sequenced 4 genetic snippets—single nucleotide polymorphisms (SNPs) of the 9p21 region of chromosome 21, which had been previously linked with heart disease). In addition, the study participants (Europeans, South Asians, Chinese, Latin Americans, and Arabs) were asked about their dietary habits.
The researchers confirmed that certain variants in these 4 SNPs were associated with a substantially increased risk of heart attack. Further analysis revealed that the type of diet study participants consumed was associated with this risk. They found that having a risky genetic variant was strongly associated with heart attack in the group with the lowest “prudent diet” scores—meaning they consumed low amounts of fruits and vegetables; risk of heart attack also was elevated, but to a lesser extent, in those with more moderate consumption of these foods. In contrast, those with risky genetic variants who had the highest “prudent diet” scores (meaning they consumed high amounts of fruits and vegetables) had a protective effect against heart attack.
The researchers also analyzed data from the prospective FINRISK study of 19 129 individuals in Finland, and found a similar association between the gene variant and dietary habits.
While needing to be confirmed in more robust studies, the findings should further the understanding of the underlying biology and pathophysiology of cardiovascular disease and could perhaps be useful in improving cardiovascular disease risk stratification that may reduce heart attacks, the researchers said.