Eye supplements

[SystemicAnomaly]

Originally Posted by sureshs

Is it good to take so much?

I addressed this, in part, in post #16. According to MayoClinic.com, it appears that even 30 mg of lycopene is safe (with2-30 mg suggested). According to MC, it may be beneficial for prostate & vision health, CVD, cancer and a number of other health concerns. Studies with lycopene from tomatoes appear to show some benefit. Not sure if extensive studies with lycopene supplementation is conclusive tho'.

I do not believe that there is any know toxicity with high lycopene intake. However, excessive levels of lycopene and carotenes (such as beta-carotene), can cause yellowing (or orange-ing) of the skin -- this condition, however, is considered harmless. Some years back, I worked with a woman who drank about 2 liters (1/2 gallon) of carrot juice daily. After several months, the yellowing effect became noticeable.

http://www.whfoods.com/genpage.php?t...xicitysymptoms


As I mentioned in post #16, it is the AOA that suggests that a beneficial daily intake of lutein should be about 10 mg/day and a daily intake of zeaxanthin should be about 2 mg/day. Lutein and the other carotenoids is considered nontoxic and well tolerated even in high doses. High intakes for 6 months to several years has yet to show any health risk. However, it is not known if several decades of high intake might have a downside. Best to get carotenoids from food sources and, if deemed necessary, take a decent supplement 3x/week.

http://www.mayoclinic.com/health/hea...Y01108&slide=8

[sureshs]

Does the daily dosage include natural sources? If so, won't taking supplements push it over the edge?

[rk_sports]

Originally Posted by SystemicAnomaly

Tried to look up details of this product on the Costco website. Note says that the product is no longer available (perhaps that only applies to online purchases). If this product really delivers this much in each softgel, then this appears quite impressive. Hopefully this Costco house brand is a quality product. Assuming that is delivers this much in each softgel, you should only need to take it every other day or 3x/week (particularly if you are eating foods with these nutrients).

I took a closer look at the product that I was using and discovered that the carotene levels and other nutrients were more than adequate but the levels of the carotenoinds, lutein & zeaxanthin, were very low (less than 100 mcg). I just picked up a very reasonably-priced Lutein Esters (20 mg) product made by NOW (Foods). Each softgel provides 10 mg of lutein and 1.34 mg of zeaxanthin + cryptoxanthin. NOW, in general, provides very high quality products. Here is a listing of the lutein products:

http://www.NowFoods.com/Search/?search=lutein

You should also be able to find some 5-10 mg lycopene products for a moderate price. CVS, Lucky's and a number of other retailers will often have one of more of their lycopene products on sale for 50% off (or BOGO free). CVS has these sales quite frequently (more than once a month?).

aha! good to know about the mcg to mg thingy..
going for Lutein Esters 20 mg

thanks for the useful info

[mary fierce]

^^
lycopene in a supplement may be of very little value. It's one of the only nutrients that has very little bioavailability until it's cooked. This is why tomato sauce is considered more nutritious than raw tomato, and why Reagan wasn't far off the mark when he declared ketchup to be a "vegetable" (for the purpose of school lunch program reckoning).

[SystemicAnomaly]

Originally Posted by mary fierce

lycopene in a supplement may be of very little value. It's one of the only nutrients that has very little bioavailability until it's cooked. This is why tomato sauce is considered more nutritious than raw tomato, and why Reagan wasn't far off the mark when he declared ketchup to be a "vegetable" (for the purpose of school lunch program reckoning).

I have never heard this (the parts in bold). Do you have any reliable sources that indicate that supplemental lycopene has very little value? Are you also saying the same of lycopene from raw tomatoes? I am well aware that ketchup, tomato paste/sauce and stewed tomatoes supposedly provide greater amounts of lycopene that raw tomatoes ( I mentioned this earlier in this thread). However, I've never heard that the lycopene in raw tomatoes and supplements is not bioavailable.

Does your claim have anything to do with the different isomers of lycopene found in food sources: all-trans versus the more useful cis-isomers?

[mary fierce]

Sources? I think this is fairly well known, have read it any number of reliable places, including biochemistry articles and texts. Do some reading on it.

[SystemicAnomaly]

Originally Posted by mary fierce

Sources? I think this is fairly well known, have read it any number of reliable places, including biochemistry articles and texts. Do some reading on it.

Sounds like you are dodging my request. I have already done quite a bit of research on lycopene and have not seen anything that suggests what you are saying. It would appear that you are making erroneous assumptions based on the the fact that cooked tomatoes deliver more usable lycopene than raw tomatoes.

Just because cooking may significantly increase the bioavailablity of lycopene in tomatoes does not mean that the lycopene in raw tomatoes or supplements is not bioavailable at all. Taka a gander at the following study done with "synthetic" lycopene:

http://www.ncbi.nlm.nih.gov/pubmed/21543537

Here is an article that discusses, in depth, the isomerization of lycopene:

http://ebm.rsmjournals.com/content/227/10/914.full

[SystemicAnomaly]

Here is a source that expands on the subject of lycopene bioavailability and metabolism in humans:

http://www.scivee.tv/node/30600
.

[mary fierce]

^^
Urging you to do some reading is not dodging your request. You look for an article or two, I base judgements on decades of work in biochemistry. When I urged you to do some reading, I meant you should do so in some depth. I'm concerned about your reading comprehension when you infer I said "lycopene in raw tomatos or supplements is not bioavailable at all." Where did you see that? I said it has "very little" bioavailability unless cooked, which is the consensus of quite alot of literature I've read on the subject.

[SystemicAnomaly]

^ My reading comprehension is just fine, thank you. You are mincing words here. Your statement that uncooked lycopone has "very little bioavailablity" certainly implies that it has little or no BV. Since you have done several decades in biochem, you could certainly provide us with a few specific sources that we can readily access that confirm your assertions. I've read quite a bit more than just the the few links that I provided. OTOH, you are asking us to take your word on your assertions.
.

[pvaudio]

Originally Posted by WildVolley

What about the rumors that pilots were taking blueberries during WW2 to increase vision, especially at night. Has anyone ever tested that, or is it just a folk story?

The RAF said they fed their pilots carrots to increase their levels of carotene. It was actually false, as their night time fighters actually had a new sort of radar, and the RAF didn't want the Germans to know about the technology that resulted in so many of their bombers being shot down.

You can actually turn your skin orange from eating too many carrots, however.

[SystemicAnomaly]

Originally Posted by mary fierce

lycopene in a supplement may be of very little value. It's one of the only nutrients that has very little bioavailability until it's cooked. This is why tomato sauce is considered more nutritious than raw tomato, and why Reagan wasn't far off the mark when he declared ketchup to be a "vegetable" (for the purpose of school lunch program reckoning).

While you say raw "lycopene" has "very little" bioavailablity, from what I've read, raw tomatoes has a lesser concentration of lycopene available than cooked tomatoes -- but I would not characterize it as "very little".

But let's look past that characterization for a while. I am curious as to why cooked tomatoes has more lycopene available than raw tomatoes. Perhaps you could shed some light on this. In the past, I assumed that that the difference was due to a difference in the type of lycopene isomers in raw tomatoes/food compared to the isomers in cooked fruits/veggies. It seems that this notion was also assumed by many nutrition scientists.

I am sure that you are aware that tomatoes and other food sources contain primarily all-trans isomers of lycopene whereas the human body prefers cis-isomers. However, some of my more recent reading indicates that cooking only converts a small percentage of all-trans to cis-isomers. (OTOH, gastric juices in the stomach can convert quite a bit of the all-trans to cis-isomers). These studies appear to disprove the earlier thinking on the bioavailbility issue.

Since there appears to be a significant difference in the concentration of lycope available from raw foods compared to cooked foods, there must be some other reason. I have not seen any sources that account for the difference and I can only speculate as to the difference occurs. There is possibly something in the raw fruit/veggie, that is diminished with cooking, that limits the available lycopene. Or possibly, the lycopene in raw foods is bound in some manner which limits its utilization. OTOH, perhaps cooking changes the chemical structure in some other manner (other than the isomerization of lycopene) that facilitates the greater availablity of lycopene. Any insights on this?

[SystemicAnomaly]

Originally Posted by sureshs

Does the daily dosage include natural sources? If so, won't taking supplements push it over the edge?

I assume that the suggested daily dosages would include both supplemental as well as regular food sources. If one is taking supplements where very high levels of a given nutrient is already derived from food, then your concern may be warranted. This is one of the reasons that I suggested taking some of these supplements 3x week instead of daily -- particularly in the case of doses that are much higher than RDA levels.

My preference, as always, would be to get as much of my nutrients from food sources rather than processed supplement forms. Supplements are just that -- supplements, not replacements. Now often, therapeutic levels are quite a bit higher than RDA levels. When this is the case, it may be difficult or impractical to obtain sufficient amounts of the desired nutrient from food sources to attain those therapeutic levels. This is where a supplemental form might be considered.

When considering fairly high levels of a nutrient, one should always look at suggested therapeutic levels carefully. Toxicity levels should be taken into account. One should look at tolerable upper intake levels (UL), when considering levels that are much higher than RDA levels. My own preference, when considering high levels of a nutrient, is to go for the low end of the suggested therapeutic level range with a daily supplement. When lower supplement doses are not available, I might take the higher dose 2-4 times a week.

If, for instance, I was going to use supplemental vitamin E, I would look for a 100 IU or 200 IU product rather than the more common 400 IU supplement. Even tho' the UL for vitamin E is 1500 IU (1000 mg), there may stilll be some issues/concerns for daily dosages in the 400-800 IU daily dose range. If I did buy a 400 IU supplement, I would use it not more than 3x/week. (Futhermore, I would look for a vitamin E supplement with mixed tocopherols).

http://en.wikipedia.org/wiki/Dietary...ecommendations

[Soul]

The supplements you mention, fish oil and vitamin D3 along with K2, might be of help with eyes. I've read a few times now that low carbohydrate diets can be helpful also with eye sight. One article that you might find helpful.

"The Modern Assault on Eyesight"

http://www.marksdailyapple.com/the-m...#axzz27i4U6Fdy

[SystemicAnomaly]

Originally Posted by Soul

The supplements you mention, fish oil and vitamin D3 along with K2, might be of help with eyes. I've read a few times now that low carbohydrate diets can be helpful also with eye sight. One article that you might find helpful.

"The Modern Assault on Eyesight"

http://www.marksdailyapple.com/the-m...#axzz27i4U6Fdy

Low-carb diets, in general, may provide some benefits as well as health disadvantages. I'm not sure that a longer-term state of ketosis from a low-carb diet is actually healthy. The Primal diet mentioned here appears to be another name (or a variation) of the Paleo diet. Some experts rate the modern versions of the caveman diet very low with regards to health concerns.

http://en.wikipedia.org/wiki/Paleolithic_diet

For athletes who burn a lot of calories, I would suggest more carbs, not less. We should also be careful about what we mean by a low-carb diet. Fruits and vegetables are primarily carbs. Lycopene, lutein and the other eye nutrients (e.g. carotenoids) are derived primarily from fruits and veggies.

With regards to carbs, what should be avoided is foods with added sugars and carbs that are highly processed (like white bread). The intake of carbs with a high glycemic load (and high glycemic index) should be minimized, especially when snacking. In the context of a well-balanced meal, some intake of these carbs is probably ok. However, one should not consume large quantities of these high glycemic foods -- sugary and high-glycemic snacks should be kept to a minimum. We should avoids "bad" carbs, not all carbs.
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