13 replies to this topic

[smithx]

This article was just released:

"Low levels of copper disrupt brain amyloid-β homeostasis by altering its production and clearance"
www.pnas.org/content/110/36/14771.full.pdf

From the Discussion:

The unique findings are as follows: (i) Cu accumulated in brain capillaries but not in the parenchyma of aging mice and selectively reduced levels of LRP1, a transporter of Aβ, which in turn contributed to increased levels of Aβ in brain. (ii) Mice chronically dosed with low levels of Cu (0.13 mg/L) in their drinking water for 90 d, starting at 2 mo of age, had the same effects on LRP1 and brain Aβ as in the aging mice.
...
Faulty Aβ clearance across the BBB, due to increased Cu levels in the aging brain endothelium may lead to neurotoxic Aβ accumulation in normal brains, which may contribute to the development of the sporadic form of AD.
...
Currently, there are no treatments for AD, and all clinical trials have so far failed. Alternative approaches are urgently needed to delay/prevent the onset of this devastating disease. Whereas the role of environmental factors in the development of the sporadic form of AD is controversial, long-term exposure to higher levels of Cu may contribute to this process, at least in some cases. D-penicillamine, a Cu chelator that does not cross the BBB, reduced oxidative stress in patients with AD. PBT2, a hydrophilic copper–zinc chaperone, which crosses the BBB, improved cognition in clinical trials (13, 61). Intracellular translocation of Zn and Cu via PBT2 may be an important mechanism of action for PBT2 (62). Our data suggest that Cu critically regulates LRP1-mediated Aβ clearance across the BBB and contributes to increased Aβ production and neuroinflammation in a mouse model of AD. Thus, Cu-specific chelating agents, chaperones, or antioxidants may reduce Cu-induced Aβ accumulation in brain, which should, by extension, prevent Aβ accumulation in brain and improve cognition in AD.

So have a screwed myself over by having taken zinc supplements with 300mcg of copper for quite a while? I even took some copper supplements for a while after I got peripheral neuropathy which some doctor said could have been caused by a copper deficiency.

If zinc really does need to be taken with copper, should zinc supplementation also be avoided?

Edited by smithx, 10 September 2013 - 07:32 AM.

[blood]

Current recommendations for safe levels of copper in drinking water are (alarmingly?) high:

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


Drinking water

... The suggested safe level of copper in drinking water for humans varies depending on the source, but tends to be pegged at 2.0 mg/l.[13]

[SeekingSerenity]

Current recommendations for safe levels of copper in drinking water are (alarmingly?) high:

http://en.wikipedia....Copper_toxicity


Drinking water

... The suggested safe level of copper in drinking water for humans varies depending on the source, but tends to be pegged at 2.0 mg/l.[13]

Wouldn't this figure vary depending on location?

[niner]

Current recommendations for safe levels of copper in drinking water are (alarmingly?) high:

http://en.wikipedia....Copper_toxicity
... The suggested safe level of copper in drinking water for humans varies depending on the source, but tends to be pegged at 2.0 mg/l.[13]

Wouldn't this figure vary depending on location?

The amount of copper that you are likely to find in water is probably most dependent on the pH and chemical composition of the water combined with the amount of copper plumbing that the water is in contact with. When I was taking an instrumental analysis course in college, I took a sample from one of the drinking fountains at my school and did a copper analysis on it. It was 1mg/liter. I hope that typical home water isn't that high, but that will depend on your plumbing, among other things.

I've seen the amount of copper in mainstream multivitamins drop over the past 5 years or so. When I was at Costco today, I looked at three: Centrum: 0.5mg (used to be 2.0, i think) Kirkland (Costco house brand): 0.9mg (used to be 3, IIRC); 1 A Day: 2.2mg (I hope it wasn't a lot more in the past!). So there's still some bad ones out there. There's a lot of variation in the amounts of copper, zinc, and selenium in multivitamins, which seems like it ought to worry people. Maybe it just represents "choice", the favorite word of marketers and fascists alike. You can choose Alzheimers, or whatever suits you.

[chemicalambrosia]

Niner, are zinc, copper, and selenium all linked to Alzheimers? Zinc and selenium at least have a pretty good reputation for positive effects at least, I'm not too familiar with copper. Do you recommend avoiding all three in supplementary form?

For reference I've been taking Bayer One A Day multivitamin(because it is cheap, minimalist, has no iron, and is from a reputable company) with 2mg copper, an additional zinc supplement with 300 mcg copper, and another 200mcg selenium pill (se-methyl-lselenocysteine).

[niner]

I didn't mean to imply that zinc and selenium had any particular role in AD or not. I was just considering them as elements that have a wide variety of dosing strategies available. Copper is the one that I worry about the most. The evidence continues to mount that we don't want a lot of poorly liganded copper (aka free copper) floating around, and that copper supplementation usually does more harm than good. Copper deficiency is of course not good, but how common it is? (not very) At the moment, you're getting 2.3 mg/day from supplements, and unknown amount from water, and whatever your diet is providing. I'll bet that's too much. I'd switch to Centrum, myself. It's cheap and has only 0.5mg Cu. I don't think that Selenium deficiency is common, and wouldn't recommend going over the RDA (55mcg) if you do supplement. It's pretty easy to get from diet. Zinc is probably worth supplementing, as deficiency is common. There's a rule of thumb that says you should get 1mg Cu for every 10mg Zn, but that should probably include dietary sources of copper. I'm not sure how solid that rule really is- probably not all that solid. You can get a ceruloplasmin level as a way of checking your bodily copper stores, which would probably be the best way to see if you are grossly high or low.

[DbCooper]

If this were true wouldn't women using IUDs since the 1950s be at a much higher risk of AD, especially since its one of the most popular forms of birth control?

[Zwergpirat]

CAVE chocolate, liver, nuts...

[chemicalambrosia]

Thanks Niner. Some of the Centrum vitamins have iron though. Centrum silver has .5 mg copper and no iron. I think I'll go with that one, and maybe just break them in half. Multi-vitamins suck, really. It shouldn't be hard to find a decent one, and now I understand why longecity made their own multi.

While searching around for different multis I found this:
"The Physicians Committee is urging the Food and Drug Administration to require vitamin manufacturers to reformulate common multivitamins that contain iron or copper, due to possible links with Alzheimer’s disease."

http://www.pcrm.org/...mins-containing

Doctors want to ban the current multi-vitamins, but manufacturers and consumers are so far behind that good alternatives don't even exist on the market.

[Darryl]

xp DbCooper - There haven't been studies on Cu IUDs and Alzheimer's risk, but I did find this:

Arnal, Nathalie, María JT de Alaniz, and Carlos A. Marra. "Alterations in copper homeostasis and oxidative stress biomarkers in women using the intrauterine device TCu380A." Toxicology letters 192.3 (2010): 373-378.

The Cu concentration was higher in women with IUDs, concomitantly with time-dependent increases in the main oxidative stress biomarkers (TBARS, protein carbonyls, glutathione and nitrates + nitrites), hepatic enzymes (LDH and transaminases), MTs and CRP. We concluded that the use of Cu-IUDs for more than 2 consecutive years should be avoided in order to prevent oxidative damage.

Edited by Darryl, 13 September 2013 - 02:25 AM.

[blood]

Centrum silver has .5 mg copper and no iron. I think I'll go with that one, and maybe just break them in half

Wouldn't something like this be safer (taking 1 or 2 caps/ day, not the 3-6 suggested on the label)? No copper, no iron.

http://au.iherb.com/...ggie-Caps/18134

Edited by blood, 13 September 2013 - 02:43 AM.

[timar]

Probably the most cost efficient option would be to get the Life Extension Two-per-Day and take half a tablet a day (1/4 dose). This way you will get about the same RDAish amount of most vitamins and trace minerals as from Centrum & Co (except vitamin A and folate, which shouldn't be a problem if you eat your greens), without the iron and copper, yet with superior forms/amounts of some nutrients (B12, selenium) and even a pinch of lipoic acid, boron and other stuff most multis lack.

Edited by timar, 13 September 2013 - 07:29 AM.

[chemicalambrosia]

Thank you blood and timar, both were better options than what I was going to do. I ordered the Life Extension two-per day. It is cheaper than the Thorne multi, and has less vitamin e(something I don't want to mega dose). It looks like it is a much better choice than the majority of multis out there, and leaves the option of 1/2 tablet or more, since you won't overdose on stuff by taking more if you think your diet was lacking in a given period of time.

Edited by chemicalambrosia, 14 September 2013 - 07:10 PM.

[albedo]

Another reason to avoid:

 

Bioavailable copper modulates oxidative phosphorylation and growth of tumors

 

"This paper describes the mechanism by which copper mediates the interplay between the two energy-producing pathways, respiration and glycolysis. Many tumors produce increased levels of lactate, even when oxygen abounds, reflecting aerobic glycolysis (“Warburg effect”), whereas most normal tissues solely use respiration. We demonstrate that reducing systemic copper with a chelating drug impaired mitochondrial energy metabolism and decreased ATP levels despite induction of glycolysis. We propose that the metabolic phenotype of tumors is modulated in part by variable levels of copper in tumor microenvironment. Our work identifies copper as a tumor promoter by demonstrating that chronic exposure to elevated levels of copper in drinking water—to the maximum allowed in public water supplies—accelerates tumor growth in mice."

 

http://www.pnas.org/...431110.abstract