eggs are the best thing for your eyes!!!
As we LCers know, eggs are a great food, for many many reasons. One of the best reasons to eat eggs is to protect your eyes. The lutein in eggs is much better absorbed by the body than the lutein in spinach. But, seeing as spinach is also quite good for you, why not make your next eye-saving meal a spinach quiche?
I found these articles recently for my Dad and just put them all in one big word document. I hope the references come out OK.
Quote:
Eggs, a better lutein source?
29-Oct-2003
Eggs are a highly bioavailable source of lutein, the carotenoid thought to help fight disease and eyesight degeneration, shows a small trial presented in the US this week.
Major dietary sources of lutein include green vegetables such as spinach but Elizabeth Johnson from the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, reported that eggs, not often considered a source of lutein, may provide more of the nutrient than both spinach and two types of supplements found on the market. The study, presented on Sunday at the annual American Dietetic Association Conference in San Antonio, also found no difference in bioavailability between natural lutein esters and lutein supplements.
Lutein has been strongly implicated in protection against age-related macular degeneration and cataracts, thought to be due to its antioxidant power. Supplement makers are benefiting from increased consumer awareness of lutein's role in eye health, but there has been some dispute over the bioavailability of the nutrient offered in different products.
Johnson's trial tested serum lutein concentration in 10 healthy men, before and after daily consumption of 6mg lutein obtained from four different sources - eggs from chickens that had been fed marigold petals, which are high in lutein, spinach (one of the most widely known sources of dietary lutein), lutein ester supplements and lutein supplements.
Differences in serum response to the various lutein doses were observed the day after the first dose, reported Johnson. At this stage, the serum lutein response to egg was significantly greater than the supplements but not different to the spinach dose. But after nine days of a daily lutein dose, the serum lutein response was significantly greater in the egg phase than either of the supplements or the spinach.
Two studies say eggs promote eye health
Two studies published in late September conclude that eating an egg a day helps promote eye health without raising cholesterol levels.
Mittwoch, 4. Oktober 2006
Eggs provide two important antioxidants—lutein and zeaxanthin—that have been shown to protect the retina and reduce the risk of cataracts and age-related macular degeneration (AMD), the leading cause of age-related blindness. AMD affects more than 13 million Americans or 5% of people 65 and older.
The two antioxidants are part of the carotenoid family (like beta-carotene in carrots) and the only carotenoids found in the eye. People can’t make these carotenoids on their own and must get them from foods such as egg yolks, fruits, and green-leafy vegetables. Previous research has shown that lutein in eggs may be better absorbed by the body than it is from other sources, such as dietary supplements or spinach.
“The two studies on lutein and zeaxanthin provide further validation that eggs provide important eye health benefits for baby boomers and aging adults, says Donald McNamara, executive director of the Egg Nutrition Center. “They also support the 30-plus years of research that show people can enjoy an egg or two a day without negatively impacting blood cholesterol levels, something that has been misunderstood by both health professionals and the public.”
In one of the studies published in the Journal of Nutrition, 24 women ages 24 to 59 were randomly assigned to one of three groups: a group that consumed a sugar pill daily or one of two egg groups. Women in both egg groups ate six eggs a week for six weeks. The eggs contained either 330 micrograms or 960 micrograms of lutein and zeaxanthin.
Zeaxanthin levels significantly increased for both egg groups and lutein levels increased for the women in the first egg group. Eye pigments that help protect the retina by blocking out harmful light significantly increased in both egg groups. And interestingly, cholesterol levels significantly increased in the group that consumed the sugar pill but did not increase in either egg group.
The other random control study published late last month also showed that eating an egg a day significantly increases lutein and zeaxanthin levels without raising cholesterol. Thirty-three men and women over the age of 60 took part in each phase of a four-phase study. Lutein and zeaxanthin levels increased by 26% and 38%, respectively, after participants ate an egg a day for five weeks. There was no increase in levels of these nutrients during a five-week period when participants ate egg substitutes (that do not have the antioxidants) daily, nor during two, three-week periods when no eggs or egg substitutes were consumed. Cholesterol levels did not differ during any phase of the study.
“Many people think they are doing themselves a favor by only consuming egg substitutes or egg whites,” says Marcia Greenblum, a registered dietitian. “But the fact is, many of an egg’s nutrients are found in the yolk, including most of the choline and vitamin B12, and about 40% of the protein.”
Nutrient Interactions
A human study published in the August 2004 issue of the Journal of Nutrition shows that lutein is much better absorbed from egg yolk than lutein supplements or even spinach.
A carotenoid, lutein is found in green vegetables, especially spinach, as well as kale and broccoli. But egg yolks, although they contain significantly less lutein than spinach, are a much more bioavailable source whose consumption increases lutein concentrations in the blood many-fold higher than spinach.
Although the mechanism by which egg yolk increases lutein bioavailability is not yet known, it is likely due to the fats (cholesterol and choline) found in egg yolk. As mentioned above, lutein, like other carotenoids, is fat-soluble, so cannot be absorbed unless fat is also present. To maximally boost your lutein absorption, we suggest enjoying your spinach, whether steamed, sautéed or fresh in spinach salad, with a little olive oil and a topping of chopped hard-boiled egg. For a flavorful, quick and easy recipe featuring eggs and spinach, try our Poached Eggs over Spinach and Mushrooms.(October 11, 2004)
Beta-carotene supplements reduce blood levels of lutein, suggesting that carotenoids may compete with each other for absorption.
Supplementing your diet with pectin or other forms of supplemental dietary fiber such as guar, wheat bran, alginate, or cellulose may decrease the absorption of lutein.
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