What tastes like a cross between a cranberry and a sour cherry, brightens trail mix, and boosts vision health? The answer: Goji berries, the bright red fruit found at your local health-food or grocery store.
The superfood originates from the northwest regions of China, where it was traditionally used in soups and herbal tea. Now popular in the U.S., many Americans enjoy blending them into smoothies or adding them to rich, homemade chocolate bark. Goji berries are well-known for their impressive antioxidant properties, such as their ability to boost immune health and reduce inflammation, via the Journal of Medicinal Food and the Journal of Pharmacognosy Research. In fact, some researchers consider them to be the richest natural source of antioxidants.
One of the best reasons to pick up a bag of these bright red berries is for their ability to improve eye sight. According to research in the International Journal of Ophthalmology, a daily supplementation of goji berries can improve symptoms of macular degeneration, or age-related deterioration in the eyes. The disease is progressive and attacks the central area of the retina, which leads to serious visual impairment and even irreversible vision loss.
To conduct the study, investigators recruited 114 patients who were in the early stages of age-related macular degeneration (AMD) and were between 59 and 92 years old. Researchers then split the patients into two groups: Those who consumed 25 grams of goji berries per day, and those in a control group. All participants continued with their normal diets. Over the course of 90 days, the research team tracked patient levels of lutein and zeaxanthin, two carotenoids that are naturally occurring in goji berries and help give the fruit its pigment. While the lutein levels in participants eating goji berries did not increase significantly, zeaxanthin levels did. Those with high zeaxanthin levels also performed better on vision tests and physical eye tests conducted by an optometrist. There were no detectable adverse effects to 90 days of goji berry supplementation.
Why is zeaxanthin so important? First, this potent carotenoid makes up almost 60 percent of all carotenoids in goji berries, as noted in the journal of Oxidative Medicine and Cellular Longevity. That means that consumption of these fruits will give patients a tremendous boost of this plant nutrient. Second, a growing body of research confirms that zeaxanthin is “retinoprotective,” meaning it actively works to combat degeneration in the retina. Indeed, another study published in the Journal of the American Academy of Optometry found that adults between 65 and 70 years old who drank goji berry juice daily for 90 days experienced higher levels of zeaxanthin and antioxidants. Those same adults did not experience further degeneration in their eye sight, while adults in the control group did.
Why does zeaxanthin help eye sight? Scientists believe that the antioxidant combats oxidative stress by binding to free radicals, which are damaging, unstable molecules that are produced when the eyes are exposed to oxygen and light. By binding to free radicals, zeaxanthin may delay or prevent degeneration in the retina, via a 2015 study from the Journal of Ophthalmology.
A word of caution: In some adults, goji berries can cause a severe allergic reaction, as reported in the journal of Oxidative Medicine and Cellular Longevity. They are also known to interact with certain medications, particularly blood thinners and drugs that treat diabetes and high blood pressure. A skin-prick test may be necessary to determine whether you are allergic to the fruit. Be sure to speak with your doctor to confirm whether or not goji berries interfere with a medication you are taking.
So, now that you’re armed with the knowledge that goji berries can protect your eyes, how will you incorporate them into your meals? You might try adding some fresh berries to your morning yogurt or sprinkling the dried version onto a sweet salad. A simple goji berry tea or a refreshing glass of goji berry juice can also help you boost your zeaxanthin intake. Whatever way you choose to eat your berries, just remember to keep your eye on the prize.
This article originally appeared on our sister site, First For Women.