A small but provocative study suggests that a diet high in vitamins C, D and E, the B vitamins and omega-3 fatty acids and low in trans fats might offer protection against Alzheimer’s disease.

Reporting Wednesday afternoon in the journal Neurology, researchers analyzed blood samples from 104 participants in the Oregon Brain and Aging Study. Participants’ mean age was 87; 62 percent were women. The blood levels for 30 nutrients were compared with participants’ performance on tests of thinking and memory skills. For 42 of the participants, brain MRIs were analyzed.

The researchers found that high levels of those vitamins or omega-3 fatty acids were associated with better performance on the cognitive tests and with MRIs showing less evidence of the kind of brain shrinkage typical of Alzheimer’s. Vitamins C and E and the B vitamins are commonly found in fruits and vegetables, while omega-3s and Vitamin D are found in fish and seafood.

The study also found that high levels of trans fats were linked to poorer mental thinking and memory skills and more brain atrophy. Trans fats are typically found in packaged, fast, fried and frozen foods, commercial baked goods and margarine.

The authors note that this is the first study to analyze blood samples for evidence of nutrients rather than rely on participants’ reports of their food intake. An accompanying editorial notes that the study’s focus on groups of nutrients indicating dietary patterns rather than individual nutrients might make the findings easier to implement among the general public.

The authors make clear that more, larger and differently designed studies are needed before cause-and-effect relationships can be established between intake of certain groups of nutrients and dementia risk. But their work helps narrow down the likely candidates and eating patterns that provide those nutrients, which should help focus future research.