Tag: blindness

Fish oil reduces age-related blindness

Claus Hancke

October 14, 2009

New U.S. study shows that intake of fish oil may reduce the incidence of age-related blindness by 30%

There seems to be no end to blessings from fish oil.

Fish oil is the end stages in the development of omega-3 fatty acids which is transformed from alpha-linolenic acid in a number of processes to E.g. eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) which then are converted to prostaglandin E 3 with a wide range of health-promoting properties.

The fish oils EPA and DHA are some of the strongest anti-inflammatory nutrients, we can consume. This is probably one of the reasons why they reduce the risk of blood clots, but they also reduces blood triglycerides, reduces inflammation in rheumatic diseases, enhances children’s learning capacity, reduces the risk of pre-eclampsia (pregnancy–induced high blood pressure) and premature birth, and gives brighter children from pregnant women who took fish oil and much more.

It is indeed difficult to see the end of the health-promoting properties, we can get from fish oil, and new scientific findings seems to emerge all the time which support its use.

Thus, even last week when researchers from the National Eye Institute in Bethesda, MD, USA, 7 October published a study in the American Journal of Clinical Nutrition.
Scientists have over 12 years studied 1,837 people with moderate to severe risk of age-related central blindness in the form of central atrophy or macular degeneration.

For both types of blindness, it appeared that the incidence was 30% lower in the group that took the most fish oil (0.11% of total caloric intake) compared with the group that took the least.

Although previous studies have been uncertain in its conclusions, the authors believe that the figures can be generalized, this is both a cheap and readily available intervention opportunity against risk families with high incidence of these diseases.

In times when the collective consensus have shouted in our ears that we should eat less fat, it is important to use common sense, read the research properly and stand firm.

Fat is healthy, and fat is vital!

One should obviously not wallow in margarine, french fries and chips, but make sure to eat well from the healthy fats as olive oil and especially fish oil.

It can be ingested as a liquid, as capsules, or as very attractive food.

Fish is not only healthy but also tastes very good indeed. Many people are nevertheless troubled by the increasing presence of heavy metals in fish, but if you avoid the large predatory fish as swordfish and tuna, there is significantly less in for example salmon and trout, especially if they are caught in clean rivers and lakes.

There are however problems with farmed fish, which often contains pretty much omega-6 fat, due to the fish feed composition. And this we should avoid. We already get far too much omega-6, especially linoleic acid, found in the cheap cooking oils with corn and sunflower oil, so as to avoid further bias, we must select the oily fish that are caught in the wild and not farmed.

We must remind you that in a previous newsletter we described two studies that showed that even eggs contain substances that prevent the age-related central blindness, so it may be, we soon will see a Danish ban against bread with eggs and herring. In Denmark food is not allowed to prevent a disease!

Enjoy your meal.

By: Claus Hancke, MD 

References:

  • Sangiovanni JP, Agron E, et al. Omega-3 Long-chain polyunsaturated fatty acid intake and 12-y incidence of neovascular age-related macular degeneration and central geographic atrophy: a prospective cohort study from the Age-Related Eye Disease Study, Am J Clin Nutr, 2009 Oct 7 (E-pub. Ahead of print)
  • Mares JA, Larowe TL, et al. Predictors of optical density of lutein and zeaxanthin in retinas of older women in the Carotenoids in Age-Related Eye Disease Study, an ancillary study of the Women’s Health Initiative. Am J Clin Nutr., 2006, 84(5): 1107-1122.
  • Wenzel AJ, Gerweck C, et al. A 12-wk egg intervention increases serum zeaxanthin and macular pigment optical density in women. J Nutr., 2006; 136(10):2568-73.

Remember your daily egg

Claus Hancke

November 28, 2006

Two new studies indicate that important nutrients, contained in, among other things, egg, play a part in the prevention of the most common type of age related blindness.

Macular degeneration, otherwise known as retinal calcification, is the degeneration of retinal cells in the eye’s macula (a yellow spot in the middle of the eye which is the centre of the visual field and has a high concentration of cells responsible for colour vision). Because the macula is in the centre of the eye, if one looses cells in the macula, one also looses sight in the centre of the eye. This means that peripheral vision is retained. With macular degeneration, it is possible to become oriented in, for example, a room, but it is difficult to see what lies directly ahead, including faces, the TV, or a newspaper. One retains ones sense of space, but is functionally blind. It is very irritating for sufferers because they cannot recognize their children or close friends it they meet them on the street. They cannot see their faces, only a black dot.

The first sign of macular degeneration is that straight lines aren’t seen as being straight, but bend so that text and the blinds in front of the window “bulge.” The next sign is the loss of colour vision, because the macula has the highest concentration of colour discerning cells (cones) in the eye.

Earlier studies have shown that it is possible to reduce the risk of macular degeneration with certain antioxidants. Recent studies are interesting because thy have shown that natural measures can be used to in increase the retina’s contents of important chemicals, thereby decreasing the risk of macular degeneration.

At the University of Wisconsin in Madison, USA, an analysis of 1,700 older women from the huge Women’s Health Initiative (a study over what it now a period of 15 years including 161,000 women of the ages 50 – 79) showed that their density of macula pigment was positively correlated with the amount of carotenoids such as lutein and zeaxanthin in the diet and negatively correlated with diabetes and obesity.

A coinciding intervention study was undertaken at the University of New Hampshire, USA, where a group of 24 women, aged 24-59, ate 6 eggs weekly over a period of 12 weeks.

Both lutein and zeaxanthin is found in eggs yolks from which they are readily absorbed into the blood and thereafter concentrated in the retina.

One group received eggs with 331 micrograms lutein and zeaxanthin per yolk. Another received eggs with 964 micrograms lutein and zeaxanthin per yolk and a third group received a daily sugar pill, which they were told contained lutein and zeaxanthin.

I both of the groups which ate the daily egg their levels of lutein and zeaxanthin increased. The same was not true of the group which received the sugar pill. This effect was known from earlier studies with eggs, but this study went one step further and measured the participants density of macula pigment as well as serum – cholesterol and triglycerides at the start of the study and after 4, 8, and 12 weeks.

Serum – cholesterol was not increased in either of the groups which received eggs, but both cholesterol and triglyceride levels increased significantly in the participants who received sugar pills.

Conversely, serum zeaxanthin (not lutein) as well as, importantly, the retina’s content of sight pigment increased in the eggs groups, but not in the sugar group.

Even though there are significantly more carotenoids in vegetables, such as spinach, the authors of the study prefer eggs because of their high bioavailability of lutein and zeaxanthin.

It is nice to, one more time, establish that eggs are good. And they don’t taste too bad either!

By: Vitality Council

References:
• Mares JA, Larowe TL, et al. Predictors of optical density of lutein and zeaxanthin in retinas of older women in the Carotenoids in Age-Related Eye Disease Study, an ancillary study of the Women’s Health Initiative. Am J Clin Nutr., 2006, 84(5): 1107-1122.
• Wenzel AJ, Gerweck C, et al. A 12-wk egg intervention increases serum zeaxanthin and macular pigment optical density in women. J Nutr., 2006; 136(10): 2568-2573.

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