Scientists have discovered that consuming two handfuls of a specific seed daily could help safeguard your vision as you age. A recent study indicates that eating a daily portion of pistachios could stave off age-related eye problems by boosting crucial protective compounds in the retina.

Researchers at Tufts University found that adults who ate just two ounces of pistachios daily for 12 weeks showed significant improvements in their eye health compared to those who maintained their regular diet. The research centred on measuring unique protective pigments in the retina – the light-sensitive layer at the back of the eye that is vital for sight.

These protective pigments, known as macular pigment, act like internal sunglasses for your eyes. They help filter out harmful blue light and protect the retina from damage that can lead to age-related macular degeneration (AMD), one of the main causes of sight loss in older adults.

What makes pistachios so beneficial is the fact they contain substantial amounts of lutein, a beneficial compound that accumulates in the retina to form these protective pigments. Moreover, the natural fat content of pistachios could aid the body in absorbing lutein more effectively.

The research, published in the Journal of Nutrition, involved 36 healthy adults aged between 40 and 70, who typically consumed low amounts of foods containing lutein. Participants were split for the study; half added two ounces of unsalted pistachios to their daily intake, while the remainder kept their regular diet unchanged. After six weeks, those who had a pistachio-enriched diet displayed significant improvements in eye health related to macular pigment levels—advantages that remained steady throughout the study’s 12-week span.

The control group did not see comparable changes. Dr Tammy Scott, lead author of the research and a distinguished neuropsychologist, said in a press statement: “Our findings indicate that pistachios are not only a nutritious snack, but they may also provide significant benefits for eye health. This is especially important as people age and face higher risks of vision impairment.”

Two ounces of pistachios, which are often referred to as nuts when they’re actually seeds, translates to about two generous handfuls or somewhere between 50 and 100 kernels.