Eating pistachios could significantly improve eye and brain health

A recent study by Tufts University's Friedman School of Nutrition Science and Policy reveals that pistachios, beyond being a tasty snack, could significantly enhance eye health.

The research found that daily pistachio consumption improves macular pigment optical density (MPOD), a measure that bolsters the eyes against blue light damage and potentially lowers the risk of age-related macular degeneration (AMD), one of the most common causes of blindness among older adults.

This finding comes at a time when vision loss is a top health concern, with Americans ranking it above other major health worries, according to a survey by the American Foundation for the Blind.

The main contributor to these health benefits is lutein, a potent antioxidant found in pistachios. Typically low in most American diets, lutein and its counterpart zeaxanthin are carotenoids that accumulate in the retina, particularly in the macular region, where they play a crucial role in protecting the eyes from harmful blue light.

These carotenoids are known for their antioxidant properties, acting as natural filters for blue light and helping to shield the retina from damage that can lead to AMD.

The Tufts University trial tested the effects of adding 2 ounces of pistachios per day to a regular diet in a group of healthy adults aged 40 and above over 12 weeks. Results showed that MPOD levels began to increase significantly within six weeks and continued to improve throughout the study.

Dr. Tammy Scott, a clinical neuropsychologist and lead author, explains, “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.”

This increase in MPOD is crucial as it signifies a heightened level of retinal protection. High MPOD levels are associated with lower risks of AMD, making pistachios a potential dietary ally for maintaining long-term eye health. Furthermore, pistachios are unique among nuts in that they contain measurable amounts of lutein, making them a valuable addition to diets that may lack this essential nutrient.

Though lutein is found in many vegetables, such as leafy greens, the way it is absorbed by the body can vary widely depending on its source. Since lutein is fat-soluble, consuming it with a fat source increases its bioavailability. For example, studies show that lutein in egg yolks is more bioavailable than that in vegetables because the fat content aids absorption. Pistachios, which are rich in mono- and polyunsaturated fats, offer a similar advantage, enhancing the body’s uptake of lutein.

Participants in the study who began with a low daily intake of lutein showed a rapid increase in blood lutein levels within just six weeks. Dr. Scott elaborates, “By simply incorporating a handful of pistachios into your diet, you can improve your intake of lutein, which is crucial for protecting your eyes.” The study found that 1.6 mg of lutein in two ounces of pistachios was enough to double the average American's daily intake, addressing a dietary gap for many people.

Interestingly, the health benefits of lutein extend beyond the eyes. Dr. Elizabeth Johnson, a co-investigator, notes, “Lutein crosses the blood-brain barrier, where it may help reduce oxidative stress and inflammation.” Accumulating in the brain, lutein has been linked to improved cognitive functions such as memory and processing speed. Higher lutein levels are associated with better cognitive performance, suggesting that pistachios could contribute to overall brain health as well as eye health.

This dual role of lutein in supporting both eye and brain health points to a broader potential benefit of pistachios in healthy aging. As people grow older and face increased risks of both visual and cognitive decline, incorporating lutein-rich foods like pistachios could offer a natural, accessible way to support these critical areas.

These findings underscore the potential of dietary changes to positively impact health, particularly in reducing the risk of conditions like AMD that affect millions of older adults. With daily pistachio consumption now linked to improvements in MPOD and potentially to brain health, this research provides a compelling reason to add this nutrient-packed nut to your daily diet.

As Dr. Scott summarizes, “Including pistachios as a regular part of one’s diet may be a simple yet powerful strategy for supporting long-term eye and cognitive health.”

Note: Materials provided above by The Brighter Side of News. Content may be edited for style and length.

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