You can always change this.

There is a growing body of research indicating that the consumption of wild blueberries has positive effects on health. For example, an antioxidant called anthocyanin seems to be responsible for improved night vision and may also ease eye-fatigue.

Here is what I think the researchers have omitted to investigate: it is not merely the consumption of the berries, but (and perhaps mostly) it is the picking up AND cleaning the blueberries that demand the vision’s increase sensitivity 1) to green-blue differences during picking and 2) to nearly imperceptible trash that needs to be hand-cleaned before the berries are further processed.

It is not very surprising that people who pick and clean blueberries also do consume them afterwards. Thus, the omnibus effect of blueberries need to be further studied to figure out what are the partial contributions of each of picking, cleaning, and consumption.

If the hypothesis that it is indeed the picking and cleaning of the berries that mostly affect vision is true, then one might easily extend the research on other species of berries, or on any other natural products whose consumption requires one to first employ advanced vision skills.