A new study is giving more reasons to eat a Mediterranean-style diet, while providing evidence it may cut the genetic risk of dementia and Alzheimer's disease.

The award-winning Mediterranean diet helps prevent dementia, especially in people at highest genetic risk, according to a new study.

Compared with the common APOE3 allele, carrying one APOE4 allele increases Alzheimer's risk by three to four times, and carrying two alleles increases risk eight to 12 times. Up to 25% of people carry one copy of APOE4, and 2% to 5% carry two copies.