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The three plant pigments, characterized as xanthophyll carotenoids, make up the macular pigment (MP) in the human eye. This is the yellow pigment found only in the macula of the retina, which controls central visual acuity and color vision. Macular pigment also is a powerful antioxidant and helps protect the retina from damaging effects of high-energy visible light (blue light).

In the study, 53 healthy subjects with low baseline concentrations of MP took a daily supplement containing 10 mg lutein, 10 mg meso-zeaxanthin and 2 mg zeaxanthin. A control group of 52 subjects with similar macular pigment levels took a placebo pill daily.

Compared with the placebo, the supplement containing macular pigments produced significant improvements in contrast sensitivity at two different measures of visual target faintness compared with background brightness (6.0 and 1.2 cycles per degree).

Contrast sensitivity (CS) is a more sensitive measure of visual function than conventional visual acuity testing, which uses black letters on a white background. CS testing evaluates the faintest target a person can see, whereas visual acuity testing measures the smallest (high contrast) target a person can see.

In a live webinar, lead investigator John M. Nolan, PhD, of Nutrition Research Centre Ireland (Waterford, Ireland), explained that the study results suggest that dietary supplementation of the macular carotenoids can have meaningful effects on visual function. These include improvements in driving vision, night vision, sports vision and one’s overall enjoyment of the visual world.

The researchers also noted that concentrations of macular pigments in the retina decrease with age. They speculated that visual improvements are likely to be noticed by all adults who enrich their macular pigment levels with supplements, not just individuals with low baseline MP concentrations.

New research indicates that leafy greens may be even healthier than we thought. While veggies like spinach, kale and collard greens may not be able to cure glaucoma, eating them regularly may help protect you against ever developing the most common form of the disease, known as primary open angle glaucoma (POAG).

Researchers at Brigham and Women’s Hospital and Harvard Medical School followed more than 100,000 men and women who were enrolled in two major medical studies for a period of more than 28 years. Everyone in these studies was 40 years or older, and none had glaucoma at the start of the study.

The patients received eye exams every two years, and throughout the course of the studies, 1,483 people developed POAG. When the researchers looked at the diets of the study participants, they noted a strong similarity among those who did not develop glaucoma — these people ate more leafy greens. In fact, greater intake of green leafy vegetables was associated with a 20 percent to 30 percent lower risk of POAG.

The association was even stronger for POAG with early paracentral visual field loss, a common subtype of POAG. The research revealed that people who ate a lot of leafy greens had a 40 percent to 50 percent lower risk of acquiring this form of the disease.

Data for the study was gathered from two long-term studies — the Nurses’ Health Study and the Health Professionals Follow-up Study — that followed 100,000 subjects (63,443 women and 38,603 men) ages 50 and older for more than two decades. None of the participants had diagnosed macular degeneration, diabetes, cardiovascular disease or cancer at the beginning of the study periods.

Blood levels of lutein and zeaxanthin were estimated based on diet and food intake questionnaires administered throughout the study period and the bioavailability of the carotenoids in the foods eaten. Associations between these scores and development of AMD were then determined.

At the end of the study period, there were 1,361 cases of intermediate AMD and 1,118 cases of advanced AMD ( visual acuity of 20/30 or worse) among the study participants. Comparing the incidence of macular degeneration among participants with lutein and zeaxanthin scores in the top 20 percent versus those with scores in the bottom 20 percent, the researchers "found a risk reduction for advanced AMD of about 40 percent in both women and men" among those whose diets contained the most carotenoids. Also, predicted plasma scores for other carotenoids — including β-cryptoxanthin, alpha-carotene and beta-carotene — were associated with a 25 to 30 percent lower risk of advanced AMD when comparing these same subgroups.

The study authors concluded the results of the study "further strengthen the evidence base for a protective role of lutein and zeaxanthin" (against macular degeneration). They also said, "Because other carotenoids may also have a protective role, a public health strategy for increasing the consumption of a wide variety of fruits and vegetables rich in carotenoids could be most beneficial and compatible with current dietary guidelines."

The study, published online in October 2015 by the American Medical Association journal JAMA Ophthalmology, was conducted by scientists affiliated with the following institutions: Department of Nutrition, Harvard T. H. Chan School of Public Health (Boston, Massachusetts); Warren Alpert Medical School, Brown University (Providence, Rhode Island); Department of Epidemiology, Brown School of Public Health (Providence, Rhode Island); Brigham and Women’s Hospital, Harvard Medical School (Boston); and University of Utah School of Medicine (Salt Lake City).

Due to poor eating habits, American children of all ages (and especially adolescents) are missing key nutrients. That’s the conclusion of Purdue University nutrition researcher Heather Eicher-Miller, PhD, during her presentation at a meeting of the Institute of Food Technologists in July 2015.

It can be particularly challenging for adolescents to meet their nutritional needs because of accelerated physical growth during this stage of life and because teens make more independent food choices that often lack key nutrients, according to Dr. Eicher-Miller.

She and her Purdue colleagues conducted a review of research on nutritional gaps in children over the last 10 years. They found kids in the U.S. frequently were deficient in vitamins A, D, E and K (found in green vegetables), calcium and magnesium.

In a study by Purdue University researchers, 16 young men ate three versions of a salad containing tomatoes, carrots, romaine lettuce, baby spinach and Chinese wolfberries (also called goji berries). One version had no egg; the second version had one and a half scrambled whole eggs; and the third had three scrambled whole eggs.

Eating the cooked eggs increased the absorption from three- to nine-fold of the carotenoids in the vegetables, including beta-carotene, alpha-carotene, lycopene, lutein and zeaxanthin. (The egg yolks also contain lutein and zeaxanthin.) Many carotenoids are considered eye health boosters.