We found that people who ate fish one or more times a week had 13 percent slower decline in thinking ability over time, ... People who rarely eat fish have a somewhat faster decline in their thinking ability over time.
The rate of (mental) decline was reduced by 10 percent to 13 percent per year among persons who consumed one or more fish meals per week compared with those with less than weekly consumption,
We found that people who ate one fish meal a week had a 10 percent slower annual decline in thinking, ... Those who ate two fish meals a week showed a 13 percent slower annual decline.
This early stage in the research shows that eating fish may help to slow one's decline in their thinking ability as they age,