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Eye. Credit: Wikipedia

Eating a handful of dried goji berries appears to have health benefits for the eyes - they may prevent or slow down age related macular degeneration (AMD). Goji berries contain high levels of lutein and zeaxanthin. These carotenoids are essential components for eye health, and are associated with a reduced risk of cataract development and AMD.

University of California researchers found that 14 healthy middle-aged adults  eating a handful (28 grams or 1 ounce) of dried goji berries 5 days a week for 90 days increased the density of protective pigments in their eyes (macular pigment optical density or MPOD). This is an optical biomarker for AMD. Their skin carotene scores also increased.

However, the 13 persons taking lutein and zeaxanthin in the form of dietary supplements (6 mg lutein and 4 mg zeaxanthin) did not have these beneficial changes in the eye. Their skin carotene scores also did not increase. These results are similar to many studies finding the same thing - eating actual foods has many health benefits, but not dietary supplements.

Dried goji berries. Wikipedia

Bottom line: Eat more servings of foods rich in lutein and zeaxanthin.

Foods with high levels of both lutein and zeaxanthin include: dried goji berries, parsley, spinach, kale, collard greens, turnip greens, mustard greens, corn, basil, leeks, egg yolks, pistachios, peas, broccoli. Slightly lower levels are in: lettuce, green and red peppers, carrots, kiwi, grapes, squash, pumpkin, corn tortillas, corn chips, Einkorn wheat, and durum wheat.

Most fruits (tangerines, raspberries, papayas, peaches, oranges, cherries, blueberries) also contain lutein and zeaxanthin, but in smaller amounts.

From Science Daily: Dried goji berries may provide protection against age-related vision loss

Regularly eating a small serving of dried goji berries may help prevent or delay the development of age-related macular degeneration, or AMD, in healthy middle-aged people, according to a small, randomized trial conducted at the University of California, Davis.  ...continue reading "Goji Berries Benefit Eye Health"

New research further confirms a link between higher lutein levels (as measured in the blood) and the preservation of "crystallized intelligence" in older adults.  Crystallized intelligence is the ability to use the skills and knowledge one has acquired over a lifetime. Lutein is in foods such as leafy green vegetables, cruciferous vegetables (broccoli, brussels sprouts, cauliflower, and cabbage) and egg yolks. Lutein is also found in small amounts in other fruits and vegetables. Bottom line: eat a variety of fresh fruits and vegetables daily. [Original study.]Medical Xpress:

Study links nutrition to brain health and intelligence in older adults

A study of older adults links consumption of a pigment found in leafy greens to the preservation of "crystallized intelligence," the ability to use the skills and knowledge one has acquired over a lifetime.

Lutein (LOO-teen) is one of several plant pigments that humans acquire through the diet, primarily by eating leafy green vegetables, cruciferous vegetables such as broccoli, or egg yolks, said University of Illinois graduate student Marta Zamroziewicz, who led the study with Illinois psychology professor Aron Barbey. Lutein accumulates in the brain, embedding in cell membranes, where it likely plays "a neuroprotective role," she said. "Previous studies have found that a person's lutein status is linked to cognitive performance across the lifespan," Zamroziewicz said. 

The study enrolled 122 healthy participants aged 65 to 75 who solved problems and answered questions on a standard test of crystallized intelligence. Researchers also collected blood samples to determine blood serum levels of lutein and imaged participants' brains using MRI to measure the volume of different brain structures. The team focused on parts of the temporal cortex, a brain region that other studies suggest plays a role in the preservation of crystallized intelligence.

The researchers found that participants with higher blood serum levels of lutein tended to do better on tests of crystallized intelligence. Serum lutein levels reflect only recent dietary intakes, Zamroziewicz said, but are associated with brain concentrations of lutein in older adults, which reflect long-term dietary intake. Those with higher serum lutein levels also tended to have thicker gray matter in the parahippocampal cortex, a brain region that, like crystallized intelligence, is preserved in healthy aging, the researchers report..... "Our findings do not demonstrate causality," Zamroziewicz said. "We did find that lutein is linked to crystallized intelligence through the parahippocampal cortex."

A new study that tracked people more than 20 years found that a diet high in carotenoids - found in brightly colored fruits and vegetables (such as carrots, orange peppers, spinach, broccoli) - is linked to lower levels of macular degenaration (an age linked vision ailment).

Note that the link is found with real foods and not supplements (the researchers did not look at supplements). From Medical Xpress:

Carrots do help aging eyes, study shows

Your parents may have told you, "Eat your carrots, they're good for your eyes," and a new study suggests they were on to something. Pigments called carotenoids—which give red or orange hues to carrots, sweet potatoes and orange peppers, or deep greens to produce like spinach, broccoli and kale—may help ward off the age-linked vision ailment known as macular degeneration, researchers said.

Age-related macular degeneration (AMD) is one of the most common causes of vision loss, especially in the elderly. It affects the macula, the center part of the retina, and can lead to declines in sharp central vision and even blindness, experts say. 

Scientists have already linked a variety of factors to the condition including genetics, smoking and nutrition, said Bernstein, who was not involved in the new study. Prior research has produced mixed findings about links between carotenoids and macular degeneration, the researchers said. 

In the new study, Wu's team looked at data from health surveys that tracked people aged 50 and older—more than 63,000 women and almost 39,000 men—from 1984 or 1986 until 2010. Participants were all nurses and other health professionals. Overall, about 2.5 percent of study participants developed either intermediate or advanced forms of the eye condition during the years of the study.

Wu's team found that people who consumed the very highest levels of carotenoids known as lutein and zeaxanthin had a 40 percent lower risk of the advanced form of AMD compared to those who ate the veryleast. Other carotenoids, including beta cryptoxanthin, alpha carotene and beta carotene, may also play protective roles," Wu added. People who consumed the very highest amount of these carotenoids—found in foods such as carrots and sweet potatohad a 25 to 35 percent lower risk of the advanced form of the illness, the findings showed.

Researchers did not find any link between the carotenoids and the intermediate form of macular degeneration, however. Lutein is found in eggs and dark leafy vegetables including broccoli, kale and spinach, Bernstein said. Zeaxanthin is harder to find in the diet, he said, but you can get it from corn, orange peppers and goji berries. Wu noted that both lutein and zeaxanthin concentrate in the macula, where they are thought to protect it from damage from oxygen and light.

Bernstein cautioned that the study has some weaknesses. It's based on people's recollections of their diets, he said, and doesn't examine the levels of the carotenoids that actually made it into their bodies and eyes. Still, he praised the research.... However, he said, a diet high in fruits and vegetables is important, especially colorful vegetables. Consume several servings a day, he advised.

Eating green leafy vegetables and other brightly colored fruits and vegetables containing vitamin K, lutein, folate and beta-carotene were linked to keeping the brain healthy in older adults and slowing cognitive decline. Researchers found that older people who ate one to two servings per day had the cognitive ability of a person 11 years younger than those who consumed none. From Science Daily:

Eating green leafy vegetables keeps mental abilities sharp

Something as easy as adding more spinach, kale, collards and mustard greens to your diet could help slow cognitive decline, according to new research. The study also examined the nutrients responsible for the effect, linking vitamin K consumption to slower cognitive decline for the first time...."Since declining cognitive ability is central to Alzheimer's disease and dementias, increasing consumption of green leafy vegetables could offer a very simple, affordable and non-invasive way of potentially protecting your brain from Alzheimer's disease and dementia."

The researchers tracked the diets and cognitive abilities of more than 950 older adults for an average of five years and saw a significant decrease in the rate of cognitive decline for study participants who consumed greater amounts of green leafy vegetables. People who ate one to two servings per day had the cognitive ability of a person 11 years younger than those who consumed none. When the researchers examined individual nutrients linked with slowing cognitive decline, they found that vitamin K, lutein, folate and beta-carotene were most likely helping to keep the brain healthy.

To conduct the study, Morris' research team gathered data from 954 participants from the Memory and Aging Project, which aims to identify factors associated with the maintenance of cognitive health. The participants, whose age averaged 81, reported their daily food and beverage intake by answering a detailed 144-item questionnaire at the beginning of the study.... They followed participants for 2 to 10 years, assessing cognition annually with a comprehensive battery of 19 tests and adjusted for age, sex, education, smoking, genetic risk for Alzheimer's disease and participation in physical activities when estimating the effects of diet on cognitive decline.

"With baby boomers approaching old age, there is huge public demand for lifestyle behaviors that can ward off loss of memory and other cognitive abilities with age," said Morris. "Our study provides evidence that eating green leafy vegetables and other foods rich in vitamin K, lutein and beta-carotene can help to keep the brain healthy to preserve functioning." In addition to green leafy vegetables, other good sources of vitamin K, lutein, folate and beta-carotene include brightly colored fruits and vegetables.