7 replies to this topic

[EMP]

With great success I've been able to reduce the eyestrain caused by excessive computer use at work with astaxanthin. I've varied with doses ranging from 4 to 10 mg and concluded that 10 mg is a good dose. Additionally, I'm considering to add either lutein or bilberry extract. Is there any studies on the use of either of them in otherwise healthy young people?

Obviously, I'm not looking for a supplement that helps with age related macular degeneration.

[Lufega]

What type of product are you using ? Are you taking anything else that might have this effect as well ?

[maxwatt]

I believe the available bilberry extracts are Chinese counterfeit or poor quality at best. Perhaps some actual berry extract mixed with a lot of dextrin, or a little actual extract but from twigs, leaves and maybe a few berries and maybe some blue dye. Blueberry extracts from the US would be a better source of whatever benefit can be had with this.

Lutein does protect the cells of the retina, but I don't expect either to help. I'm dubious that astaxanthin had more than a placebo effect.

Glasses for reading are optimized for a distance of 16 inches, while typical computer screen distance is 21 or even 24 inches. Even if you don't wear glasses, you might reduce strain on the eye muscles that are troubling and causing the symptoms of eye-strain. An optometrist can fix you a prescription for this use. The supplements might help with the condition of your retina, but eye strain is typically due to focus and acuity problems that have more to do with the eye's optics.

[EMP]

What type of product are you using ? Are you taking anything else that might have this effect as well ?

Apart from the Now Foods Astaxanthin, I'm not taking any other supplements that is likely to cause this reduction in eye strain. However, I do certain eye exercises on a regular basis and although these help greatly, I notice a very significant improvement after taking astaxanthin for 2 weeks.

I believe the available bilberry extracts are Chinese counterfeit or poor quality at best. Perhaps some actual berry extract mixed with a lot of dextrin, or a little actual extract but from twigs, leaves and maybe a few berries and maybe some blue dye. Blueberry extracts from the US would be a better source of whatever benefit can be had with this.

Lutein does protect the cells of the retina, but I don't expect either to help. I'm dubious that astaxanthin had more than a placebo effect.

Glasses for reading are optimized for a distance of 16 inches, while typical computer screen distance is 21 or even 24 inches. Even if you don't wear glasses, you might reduce strain on the eye muscles that are troubling and causing the symptoms of eye-strain. An optometrist can fix you a prescription for this use. The supplements might help with the condition of your retina, but eye strain is typically due to focus and acuity problems that have more to do with the eye's optics.

I've been more than once to see an optometrist and I've been given a prescription for glasses that I should use solely for computer use and are convenient for car driving. Having used them for over a year, I can tell you that - although it's substantially more comfortable - I always ended up having tired eyes at the end of the day anyway. I then went to see a specialist who told me that certain eye exercises would help me greatly. Since English is not my native languages, I hope I can make myself understandable but the issues are related to accommodation difficulties and relatively weaker inner muscles of the eyes, these muscles need to be trained to keep the outer and inner muscles balanced and prevent the more dominant muscles from making my eyes exhausted.

Moreover, I am convinced that the astaxanthin supplements have not given me mere placebo effects and a number of studies have been conducted in both China and Japan that confirm its effectiveness:

Since Dr. Tso’s groundbreaking work, other scientists have found further benefits for the eyes when using Natural Astaxanthin. For example, eye fatigue is a serious problem in many of today’s occupations. Working for long periods at visual display terminals reportedly induces various visual problems such as eye strain, blurring and diplopia (a disorder of vision in which two images of a sin- gle object are seen because of unequal action of the eye muscles – also called double vision). In a double blind study performed in Japan, after four weeks of supplementation with 5 mg of Astaxanthin per day (extracted from Haematococcus algae meal) the authors reported a 46% reduction in the number of eye strain subjects. They also found higher accommodation amplitude (the adjustment in the lens of the eye that allows it to focus) in subjects who used visual display terminals. The mechanism of action is still not understood, but it’s most likely due to Astaxanthin’s potent antioxidant properties (Nagaki, et al, 2002). Additional research in the area of eye fatigue has been car- ried out. In fact, there are now nine different positive human clinical stud- ies that have been published in the area of eye fatigue. Two different dosage levels were tested for eye fatigue by a group led by Dr. Nakamura in 2004. They found positive effects at 4 mg per day, but found a better result at 12 mg per day (Nakamura, et al, 2004).

Another group of Japanese researchers found similar results in another human clinical study. This double blind study was done to evaluate Astaxanthin’s effect on eye fatigue and visual accommodation. Forty subjects were divided into placebo and treatment groups, with the treatment group receiving 6 mg of Astaxanthin for four weeks. The results were that three separate visual parame- ters were found to have statistically significant benefits from Astaxanthin supple- mentation. This research established an optimum daily dose for eye fatigue at 6 mg per day (Nitta, et al, 2005). Additional studies have validated this work, showing that 6 mg per day of Natural Astaxanthin supplementation for four weeks can reduce eye soreness, dryness, tiredness and blurred vision (Shiratori, et al, 2005 and Nagaki, et al, 2006). Astaxanthin may work in a preventive role for eye fatigue as compared to the curative role that has already been established. The other studies referenced above all centered on the use of Astaxanthin to cure eye fatigue. A clinical study was done on subjects whose eyes were healthy, with no signs of fatigue or strain.

Both the treatment and the placebo groups were subjected to heavy visual stim- uli to induce eye fatigue, and it was found that the treatment group recovered more quickly. This clearly indicates that Natural Astaxanthin may serve to prevent eye fatigue from occurring in healthy people (Takahashi and Kajita, 2005). It is very important to have sufficient blood flow to the eyes and the reti- na. A human clinical study examined the ability of Astaxanthin to improve reti- nal capillary blood flow. Eighteen subjects were given 6 mg per day of Natural Astaxanthin and another eighteen people were given a placebo. After four weeks it was found that the treatment group had improved retinal capillary blood flow as compared to the placebo group (Yasunori, N, 2005).
The mechanisms of action thought to enable Astaxanthin to reduce or pre- vent eye fatigue are diverse. Of course, Astaxanthin’s role as an antioxidant and anti-inflammatory must play a part. A study conducted at the Hokkaido University Graduate School of Medicine determined that Astaxanthin inhibited inflammation in the eye by blocking nitric oxide synthase (Ohgami, et al, 2003). Astaxanthin was also found to have potent antioxidant effects in the prevention of cataracts in rats’ eyes (Wu, et al, 2002). In addition, the increased blood flow to the retina surely plays a part. The final, yet very significant mechanism is improved accommodation amplitude. By enabling the lens to more easily adjust, the ability of the eye to focus is improved.
Another, very different type of human study on Natural Astaxanthin’s effects on the eyes has also yielded positive results. This study was done in Japan with subjects comprised of twenty year old men. The treatment group was given 6 mg of Natural Astaxanthin per day for four weeks. Different visual parameters were measured, with statistically significant improvement found in two different parameters for visual acuity (the ability to see detail). The greatest enhance- ment was seen in depth perception which improved by 46% in the group sup- plementing with Natural Astaxanthin (Sawaki, et al, 2002).
Of course, along with the human clinical trials, there are also pre-clinical animal studies and in-vitro experiments on Astaxanthin and eye health. One such study took the lens from the eyes of pigs and tested the ability of Astaxanthin to protect them from induced oxidative damage. This experiment found that Astaxanthin was capable of protecting the lens proteins from oxidative dam- age. In fact, Astaxanthin performed better than the antioxidant glutathione which is produced by the pig’s own body (Wu, et al, 2006).

A study done in rats was very helpful in that it measured the effect of Astaxanthin on three important inflammatory markers in the uvea (the middle layer of the eye including the iris). Inflammation in the uvea was induced, after which nitric oxide, tumor necrosis factor alpha and prostaglandin E-2 were meas- ured. The rats that had been injected with Astaxanthin had lower levels of all three inflammatory markers. The researchers concluded that Astaxanthin is effective in reducing ocular inflammation (Suzuki, et al, 2006). A previous study done on inflammation of the eye of rats yielded similar results, but also demonstrated that the effects of Astaxanthin worked in a dose-dependent fashion. Additionally, this study proved these anti-inflammatory mechanisms in-vitro (Ohgami, et al, 2003).

Source is a PDF-format book that I can provide on request and is also available on the net:

ASTAXANTHIN - Natural Astaxanthin: King of the Carotenoids (Capelli and Cysewski 2007)

Edited by EMP, 04 February 2012 - 11:12 AM.

[Deckah]

You might try lutein and maybe an extract with Zeaxanthin as well.

They also sell a type of eyebright herb which some people report, helps them with eye strain.

They also sell eye drops for strain in relation to computers, but you might try to research the ingredients if there's any info on them.

http://www.swansonvi.../ItemDetail?n=0


You might try to use f.lux . ( http://stereopsis.com/flux/ ) You can set light brightness/contract/warm color to change at different intervals
throughout the day. If you're doing any graphic/design work then this might not be an option. I used f.lux before and it worked great, but
I now just have my monitor set at a lower contract/brightness setting. I also use the adBlock element hiding plugin and take out certain portions(code)
of websites that mess with my peripheral vision.

[niner]

f.lux and AdBlockPlus are must haves for me. High dose supplemental carotenoids worry me because of their associations with cancer risk.

[EMP]

High dose supplemental carotenoids worry me because of their associations with cancer risk.

Can you elaborate and more specifically on astaxanthin...

[niner]

High dose supplemental carotenoids worry me because of their associations with cancer risk.

Can you elaborate and more specifically on astaxanthin...

As far as I know, plasma concentrations of carotenoids that come from dietary sources are inversely associated with cancer risk. However, there were two large clinical trials ( http://www.ncbi.nlm..../pubmed/8602180 and http://www.ncbi.nlm..../pubmed/7495243 ) where supplemental beta carotene increased the risk of lung and other cancers in smokers. A study that was somewhat more eye-opening, because it was not restriced to smokers, was published in 2009:

Am J Epidemiol. 2009 Apr 1;169(7):815-28. Epub 2009 Feb 10.
Long-term use of beta-carotene, retinol, lycopene, and lutein supplements and lung cancer risk: results from the VITamins And Lifestyle (VITAL) study.

Satia JA, Littman A, Slatore CG, Galanko JA, White E.

Departments of Nutrition and Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA. jsatia@unc.edu

High-dose beta-carotene supplementation in high-risk persons has been linked to increased lung cancer risk in clinical trials; whether effects are similar in the general population is unclear. The authors examined associations of supplemental beta-carotene, retinol, vitamin A, lutein, and lycopene with lung cancer risk among participants, aged 50-76 years, in the VITamins And Lifestyle (VITAL) cohort Study in Washington State. In 2000-2002, eligible persons (n = 77,126) completed a 24-page baseline questionnaire, including detailed questions about supplement use (duration, frequency, dose) during the previous 10 years from multivitamins and individual supplements/mixtures. Incident lung cancers (n = 521) through December 2005 were identified by linkage to the Surveillance, Epidemiology, and End Results cancer registry. Longer duration of use of individual beta-carotene, retinol, and lutein supplements (but not total 10-year average dose) was associated with statistically significantly elevated risk of total lung cancer and histologic cell types; for example, hazard ratio = 2.02, 95% confidence interval: 1.28, 3.17 for individual supplemental lutein with total lung cancer and hazard ratio = 3.22, 95% confidence interval: 1.29, 8.07 for individual beta-carotene with small-cell lung cancer for >4 years versus no use. There was little evidence for effect modification by gender or smoking status. Long-term use of individual beta-carotene, retinol, and lutein supplements should not be recommended for lung cancer prevention, particularly among smokers.
Comment in

Am J Epidemiol. 2009 Aug 1;170(3):401-2.

PMID: 19208726
PMCID: PMC2842198 Free PMC Article

Astaxanthin is more like lutein than beta carotene, but the complaint against astaxanthin is guilt-by-association; it's chemically related. The comment that is linked with the abstract is from a supplement manufacturer, defending lutein. He does raise a point, that 92% of the cancer cases who also used lutein supplements were smokers (30% current, 62% former). I think that's fairly close to the normal ratio for lung cancer though, particularly given that there were only 20 cases of lung cancer in lutein supplement users during the followup period. At any rate, this was the study that concerned me regarding large doses of supplemental carotenoids. In the event that you read the Satia paper, note the errata, which makes the text consistent with the tables, and specifies the dose of supplemental lutein as 20mg.

Edited by niner, 05 February 2012 - 04:05 AM.