Tuesday, April 6, 2010

Copper and Cardiovascular Disease

In 1942, Dr. H. W. Bennetts dissected 21 cattle known to have died of "falling disease". This was the name given to the sudden, inexplicable death that struck herds of cattle in certain regions of Australia. Dr. Bennett believed the disease was linked to copper deficiency. He found that 19 of the 21 cattle had abnormal hearts, showing atrophy and abnormal connective tissue infiltration (fibrosis) of the heart muscle (1).

In 1963, Dr. W. F. Coulson and colleagues found that 22 of 33 experimental copper-deficient pigs died of cardiovascular disease. 11 of 33 died of coronary heart disease, the quintessential modern human cardiovascular disease. Pigs on a severely copper-deficient diet showed weakened and ruptured arteries (aneurysms), while moderately deficient pigs "survived with scarred vessels but demonstrated a tendency toward premature atherosclerosis" including foam cell accumulation (2). Also in 1963, Dr. C. R. Ball and colleagues published a paper describing blood clots in the heart and coronary arteries, heart muscle degeneration, ventricular calcification and early death in mice fed a lard-rich diet (3).

This is where Dr. Leslie M. Klevay enters the story. Dr. Klevay suspected that Ball's mice had suffered from copper deficiency, and decided to test the hypothesis. He replicated Ball's experiment to the letter, using the same strain of mice and the same diet. Like Ball, he observed abnormal clotting in the heart, degeneration and enlargement of the heart muscle, and early death. He also showed by electrocardiogram that the hearts of the copper-deficient mice were often contracting abnormally (arrhythmia).

But then the coup de grace: he prevented these symptoms by supplementing the drinking water of a second group of mice with copper (4). In the words of Dr. Klevay: "copper was an antidote to fat intoxication" (5). I believe this was his tongue-in-cheek way of saying that the symptoms had been misdiagnosed by Ball as due to dietary fat, when in fact they were due to a lack of copper.

Since this time, a number of papers have been published on the relationship between copper intake and cardiovascular disease in animals, including several showing that copper supplementation prevents atherosclerosis in one of the most commonly used animal models of cardiovascular disease (6, 7, 8). Copper supplementation also corrects abnormal heart enlargement-- called hypertrophic cardiomyopathy-- and heart failure due to high blood pressure in mice (9).

For more than three decades, Dr. Klevay has been a champion of the copper deficiency theory of cardiovascular disease. According to him, copper deficiency is the only single intervention that has caused the full spectrum of human cardiovascular disease in animals, including:
  • Heart attacks (myocardial infarction)
  • Blood clots in the coronary arteries and heart
  • Fibrous atherosclerosis including smooth muscle proliferation
  • Unstable blood vessel plaque
  • Foam cell accumulation and fatty streaks
  • Calcification of heart tissues
  • Aneurysms (ruptured vessels)
  • Abnormal electrocardiograms
  • High cholesterol
  • High blood pressure
If this theory is so important, why have most people never heard of it? There could be at least three reasons. The first is that the emergence of the copper deficiency theory coincided with the rise of the diet-heart hypothesis, whereby saturated fat causes heart attacks by raising blood cholesterol. Bolstered by encouraging findings, this theory took the Western medical world by storm, for decades dominating all other theories in the medical literature and public health efforts. My opinions on the diet-heart hypothesis aside, the two theories are not mutually exclusive.

The second reason you may not have heard of the theory is due to a lab assay called copper-mediated LDL oxidation. Researchers take LDL particles (from blood, the same ones the doctor measures as part of a cholesterol test) and expose them to a high concentration of copper in a test tube. Free copper ions are oxidants, and the researchers then measure the amount of time it takes the LDL to oxidize. Yet questions have been raised about the relevance of this method to human cardiovascular disease, because studies have shown that the amount of time it takes copper to oxidize LDL in a test tube doesn't predict how much oxidized LDL you'll actually find in the bloodstream of the person you took the LDL from (10, 11).

The fact that copper is such an efficient oxidant has led some researchers to propose that copper oxidizes LDL in human blood, and therefore dietary copper may contribute to heart disease (oxidized LDL is likely a central player in heart disease). The problem with this theory is that there are virtually no free copper ions in human serum. Then there's the fact that supplementing humans with copper actually reduces the susceptibility of red blood cells to oxidation (by copper in a test tube, unfortunately), which is difficult to reconcile with the idea that dietary copper increases oxidative stress in the blood (13).

The third reason you may never have heard of the theory is more problematic. Several studies have found that a higher level copper in the blood correlates with a higher risk of heart attack (14, 15). At this point, I could hang up my hat, and declare the animal experiments irrelevant to humans. But let's dig deeper.

Nutrient status is sometimes a slippery thing to measure. As it turns out, serum copper isn't a good marker of copper status. In a 4-month trial of copper depletion in humans, blood copper stayed stable, while the activity of copper-dependent enzymes in the blood declined (16). These include the important copper-dependent antioxidant, superoxide dismutase. As a side note, lysyl oxidase is another copper-dependent enzyme that cross-links the important structural proteins collagen and elastin in the artery wall, potentially explaining some of the vascular consequences of copper deficiency. Clotting factor VIII increased dramatically during copper depletion, perhaps predicting an increased tendency to clot. Even more troubling, three of the 12 women developed heart problems during the trial, which the authors felt was unusual:
We observed a significant increase over control values in the number of ventricular premature discharges (VPDs) in three women after 21, 63, and 91 d of consuming the low-copper diet; one was subsequently diagnosed as having a second-degree heart block.
In another human copper restriction trial, 11 weeks of modest copper restriction coincided with heart trouble in 4 out of 23 subjects, including one heart attack (17):
In the history of conducting numerous human studies at the Beltsville Human Nutrition Research Center involving participation by 337 subjects, there had previously been no instances of any health problem related to heart function. During the 11 wk of the present study in which the copper density of the diets fed the subjects was reduced from the pretest level of 0.57 mg/ 1000 kcal to 0.36 mg/1000 kcal, 4 out of 23 subjects were diagnosed as having heart-related abnormalities.
The other reason to be skeptical of the association between blood copper and heart attack risk is that inflammation increases copper in the blood (18, 19). Blood copper level correlates strongly with the marker of inflammation C-reactive protein (CRP) in humans, yet substantially increasing copper intake doesn't increase CRP (20, 21). This suggests that elevated blood copper is likely a symptom of inflammation, rather than its cause, and presents a possible explanation for the association between blood copper level and heart attack risk.

Only a few studies have looked at the relationship between more accurate markers of copper status and cardiovascular disease in humans. Leukocyte copper status, a marker of tissue status, is lower in people with cardiovascular disease (22, 23). People who die of heart attacks generally have less copper in their hearts than people who die of other causes, although this could be an effect rather than a cause of the heart attack (24). Overall, I find the human data lacking. It would be useful to see more studies examining liver copper status in relation to cardiovascular disease, as the liver is the main storage organ for copper.  Until we have more human data, it will remain unclear whether copper deficiency is a significant contributor to cardiovascular disease.

According to a 2001 study, the majority of Americans may have copper intakes below the USDA recommended daily allowance (25), many substantially so. This problem is exacerbated by the fact that copper levels in food have declined in industrial nations over the course of the 20th century, something I'll discuss in the next post.


Tim G. said...

Hi Stephan,
Thank you for a fascinating post and another interesting angle into the possible etiology of heart disease.
Perhaps you will cover this in your next post, but I see general reluctance to use supplemental copper (short of conditions like aneurysms where it is often prescribed, usually "too little, too late" however). The first is that copper can be antagonistic to zinc, and zinc deficiency seems to be pretty endemic to our society, so I think many practitioners worry about making zinc deficiency worse. Second, copper is a significant cofactor in angiogenesis (a therapy in use by a number of integrative oncologists is copper depletion, which can stymie cancer growth and help prevent metastases) and I think at least some practitioners worry that actively supplementing copper (or recommending a high copper diet) might exacerbate cancer risk. Do you have any thoughts?

Thank you for all the time and energy you put into your blog.

Dr. Tim Gerstmar

John said...

This is interesting as Cu is uncommonly discussed--more support for eating liver. Will those eating poor diets choosing to simply supplement Cu then run into problems with Zn?

I suppose the moral of the story is to eat better instead of continually adding supplements to a sugar and vegetable oil diet. Unfortunately, most people will do whatever it takes to stick to the SAD...

Sally said...

I have a question, hope it does not seem like a stupid one to anyone, Years ago I used to wear a copper braclet because I was told it was like adding copper to my blood stream, does anyone know if it works? I supplement with some vitamines now especially vit D because I know I dont get enough and I see some people dont believe in suppliments, it is hard to just eat good foods all the time even tho some of us try harder then others or even harder then we did years ago. Anyway, I dont want to add another to make sure I get enough and would like to know if wearing copper helps.

My next interest is a story I am reading that taking orange juice (not from concentrate) will help reduce the effects of any bad foods I mihgt end up with in an emergency need to eat something like on the road during travel, Dont slam me nobody hahaha. Anyway the paper said it will help with fats not becoming so high in the blood and will even help with blood sugars, I hope you can write on that soon. Love your blogs, so much for me to learn by. Thank you.

Robert Andrew Brown said...


I do not have time to look the reference up but have read that copper in bracelets combines with sweat to form salts which to a limited extent pass through the skin and provide small amounts of copper to the body.

According to a paper I have previously referenced copper in UK food have declined by an average of 62%, and 90 plus % in dairy foods, 55% in meat and 76% in vegetables.

The decline in dairy and meat suggests our pastures are depleted, which is a depressing thought.

On a common sense basis this would suggest most of us are likely to be copper deficient compared with out ancestors.

Robert Andrew Brown said...


Here is the ref. I cannot find the link to the full free version but think I have seen one.


The mineral depletion of foods available to us as a nation (1940-2002)--a review of the 6th Edition of McCance and Widdowson.

Robert Andrew Brown said...

Thanks Stephan

ref 12 is fascinating, and means I have some reading to do (-:.

I was under the impression that sat fats could in some circumstances increase the amount of oxidation in LDLS - and presumed this was due to longer exposure to oxidants in the blood stream ?

Given the above; are results being confounded by - poorer overall antioxidant status? - type of saturated fat? - antioxidant status of dietary fat? - pre-oxidation of dietary fat? - etc which could all affect levels of oxidation of LDLs.

I need to revisit the refs.

Jenny said...

What about the copper that leaches from the hot water pipes? I'd think that must be a factor, though the mineral balance of the water might make a difference. For that matter, it might make more of a difference in a lot of things than is generally realized.

Jeremy said...

This is fascinating because I've never heard of copper deficiency despite reading a large number of blogs for the past couple of years.

Patrick said...
This comment has been removed by the author.
Patrick said...


"Hence, dietary supplements of copper or zinc at the doses used both inhibited aortic atherogenesis in the cholesterol-fed rabbits, although there was no significant additional effect when given in combination."


Adolfo David said...

Stephan, finally my muscle pains were not due to butter or saturated fats I included in my diet months ago as I believed and told you.

Reading my blood tests I could be sensitive to vitamin D3.

Chris Kresser said...

Interesting. A while back there was an article in the WAPF journal hypothesizing that excess copper (causing a copper-zinc imbalance) is responsible for all manner of health problems. I'll have to look it up to see where your arguments differ. Did you happen to read it, Stephan?

Just yesterday I was reading a book on Graves disease in which the author argued that Graves and hyperthyroid are associated with copper deficiency. Since Graves is also associated with increased risk of CHD, that's an interesting connection.

Scott W said...

In my city we drink water straight from the aquifer w/out any treatment, but who knows what's in it from a trace mineral perspective? They only report dissolved PPM of major minerals.

This trace mineral issue - depletion even in good food choices - has caused me recently to add some trace mineral drops to a glass of water once in awhile. The bottle says they basically scrape up dirt from some prehistoric lake bed in Utah and somehow liquefy it. I guess that's as close as I can get to eating a cow that ate grass growing in undepleted soil.

I don't take it every day and I'll probably never know if it is doing anything or not.

I like Kurt Harris' perspective on the issue of "supplementation." Some things (he places Omega 3 and D3 into this category if I have read him correctly) are deficient enough in our current environment that taking them is not "supplementation", but rather "replacement." Reading articles like Stephan's take on copper starts to make me feel that this could be true for trace elements.

On another note...this article is the final straw that will push me to get over my gag reflex and eat liver once a week. Good thing I work from home so I can cook it while my wife is at work. She has threatened me on this topic during past attempts.

Scott W

Ofelia said...

Apologies for being way off topic, but you really know your stuff, you're very balanced, and know when research has been done properly. The more I read the more confused I get.

I have excess hair, oily skin, acne, and thinning hair but seem to have no reason for it. It's getting worse, even though I've lost weight.

Are there any diets and/or supplements that can improve this or make it worse? I've read somewhere that having too much saturated fats can worsen it but then staying away from high-carb would help too - which doesn't leave much choice. Also, when I exercised a lot it seemed to increase too.

Not knowing what the cause of it is is making it more difficult to know what to do. GPs are of no help and I thought with your balanced knowledge of research you could point me in the right direction? Or, perhaps, someone else reading this could too? I've read lots of research papers on it but they just contradict each other.

The only option that was given to me was to exercise and to take Dianette.

Todd S. said...

From a few comments here, I take it that liver is a good source for copper and other trace minerals. This may get addressed in your next post, but what are other good foods for copper and others like magnesium?

Like many here, I'd rather eat them than swallow them in pill form.

bovinedefenestration said...

Ofelia, I have those problems, too. I've had a PCOS diagnosis since I was a teen, and the skin/hair problems are usually attributed to it. If you have weight and/or menstrual problems, it's something to look in to. It's a common problem for women, but it seems that doctors are woefully ignorant of its existence. They seem to lack sympathy for people concerned about their skin and hair, too, which sucks when it's falling out.

Regarding the acne and hair, the only solution I've found has been a very-low-carb diet consisting of real food. It takes a few months of that for my skin to heal itself, my hair to start regrowing, and body hair to lighten and thin. I'm a bona-fide sugar and wheat addict, so staying VLC for that long is a serious challenge. Regularly trying and failing to eat properly still seems to yield better results than just giving up, though.

I find sane vitamin D, K, and omega-3 supplementation do some good, as well.

As for BCPs, I was on Mircette for a long time, then Yasmin. They DID help some, but not enough to justify continuing to take them. Proper diet, exercise, and judicious supplementation seem to have better results in changing my hormone profile. Speaking of hormones, it might be good to get your thyroid looked at, too. Turned out I also had subclinical hypothyroid (most blood tests within the lab reference range, but very tender and slightly swollen gland), and a small dose of levothyroxine makes a HUGE difference. No matter what lifestyle changes I make, I still feel and look miserable without it.

If it seems like you're breaking out more when you change something, it might be worth it to give the thing you try some time. My skin flares bright red and breaks out when I change anything, for good and for ill, and it takes at least a week of doing something consistently before the flare-up settles down, if it's going to.

Anyhoo, good luck, and I hope you find something that works for you.

David L said...

I have been taking cod liver oil. Since this comes from the sea and not from depleted agricultural land, I wonder if it might be one of the best sources of copper.

Ofelia said...

Thank you so much for the reply.

I've been dealing with it since my teens too - though I'm sure my arm hair was worse before that. I was normal weight most of my life but have been up and down (in my adult life). At this moment in time I'm thin. Have you found exercise to help at all? I think I'd rather do calming exercises then something quite hard - seem to stress me out more.

Have there been any books that have helped you? I would be starting from scratch so would like to start slowly into changing my diet.

The doctor did do some blood tests - after pushing them for it - one was TSH which was 3.8 mU/L. Which other ones should I ask for?

And do any particular vitamins work or will any shop brand do?

Apologies for all the questions and thanks again - I hope so too.

dextery said...

At Nutrition.com there is a listing that shows beef liver has
15-17mg of Cu per 200 kcal serving.

Your posting reminded me of Joel Wallach, DMV author of Dead Doctors Don't Lie who for years and years has promoted the intake of minerals derived from ancient sea beds to get a complete spectrum of minerals. I seem to recall Utah ancient sea beds is his source for his product.

He was also famous for the following he used in his lectures:

Case #1 - Here's a good one. Dr S.C., 38 years old. Dead of a ruptured aneurysm. Even a turkey wouldn't die of a ruptured aneurysm! It's easy to prevent. We learned this in 1957. The government came out with its "wonder food pellet" for turkeys. Guaranteed to grow them bigger ,fatter, faster, and deader than a door nail. The farmers had to pick them up in bushel baskets, worst year ever for turkeys, they took them to the labs by the truck load, opened them up, and guess what they found? They all died of a ruptured aortic aneurysm, every last one, 50% of the entire nation's flock of turkeys..

So they knew something was missing in the food. They analyzed the liver, blood, and muscles. Copper deficiency! Your arteries' elastic fibers need copper for tensile strength. The next year the copper content in the feed was doubled, and the mortality rate from ruptured aortic aneurysms dropped to 0%!" 2 cents of Cu per turkey per lifecycle prevented the aneurysms in turkeys.

He does make the leap from turkeys to humans without documentation.

Eat your beef liver!

Kelly A. said...

My RBC zinc was tested last year and found to be at the low edge of normal, so my Dr. had me supp with about 25 mg of zinc a day. 6 months later we retested and zinc was almost to the middle of normal, but copper was below range. So she had me add 2 mg of copper to the mix. This is in addition to the 2 mg of copper and 20 mg of zinc I was already taking in the multi pack she recommended.

I can't always stomache all those pills, but my zinc and copper *both* go to the bottom of the range or below if I don't... It probably has to do with my hypothyroidism and gluten intolerance I imagine.

I've been off gluten for about 3 months and hope I'l be able to absorb more. Thanks everyone for the heads up on the liver. I have some grassfed frozen that I'm going to swallow as liver "pills" now. I was just afraid that excess copper was associated with *lower* thyroid and didn't want to make things worse. (so confusing)

Robert Andrew Brown said...

Lots of papers suggest poor digestion = poor mineral absorption.Greater numbers suffer with poor digestion.

Levels of many minerals including copper in foods of all sorts have fallen, due to a combination of factors to varying extents in the last 50 years.

We then go and refine food and throw out most of the bits with the minerals in.

We are then surprised when large portions of the population are deficient in a number of minerals.

David L

No minerals in fish oil I am afraid. That is the advantage of eating fish and shellfish if we were not busy depleting their stocks and using a big chunk of the catch to farm fish. Sadly it takes 4 of 5 tons of small wild oily fish to grow 1 ton of carnivorous marine farmed fish.

Ofelia and Bovinedefensration

PCOS and related conditions.

Omega 6 ultimately controls the production of sex hormones, and plays a big part in inflammatory conditions.

PCOS and acne are in very simple terms inflammatory conditions.

In essence excess Omega 6 and imbalances in the fat conversion pathways are significant factors in PCOS.

Reduce your Omega 6 plant based fat intake, balance with plant based Omega 3, include some Omega 3 EPA and DHA in your diet, at least half a gram of each, and some GLA.

Mineral, vitamin D, iodine etc are all part of the team and most people are short of them.

This may help explain. I wrote it. A complete rewrite is not too far off completion, and it is a big step forward hopefully, so you may want to wait.
The editing of the original version is poor but the science is OK.


sandra said...

"Levels of many minerals including copper in foods of all sorts have fallen, due to a combination of factors to varying extents in the last 50 years."

Are these new levels reflected in current nutrition databases... or do we need to assume "good sources" for copper and other minerals have less than advertised?

Miki said...

Robert Andrew Brown
The full text of the paper on the mineral depletion 1940-2002 can be found here: (http://www.mineralresourcesint.co.uk/pdf/Mineral_Depletion_of_Foods_1940_2002.pdf)
According to this paper depletion of Copper is by far the largest (-62%), compared, for example, to Iron (-37%), Calcium (-29%) or Magnesium (-19%).
A fascinating paper indeed and so is this post.

Robert Andrew Brown said...


I wondered about this and so has Stephan.

I wrote to the USDA pointing out the discrepancy between their estimates and papers on the mineral nutrient content of food, and asking for details as to when their food mineral data bases were last updated, but did not get a response, and have not followed it up.

As a generality USDA figures seem to suggest there has been no decline, which runs counter to the conclusions of the English paper cited above (and others) that mineral content has fallen, and the generality of conclusions of papers looking a nutrient density of modern varieties, which also suggests nutrient density has declined.

IF the USDA figures are incorrect then that has huge ramifications for all the nutritional trials that are based on food computations using their figures.

The level of mineral intake deficiencies would be much higher than stated, which is already frighteningly poor, and that is before impaired digestion.

Nutrient depletion is likely to impair digestion, and onward we slide towards illhealth, down the ever steeper health spiral.

On the other side of health spiral, national illhealth and medical cost, must be going up just as fast.

One day we will have to find a way of attributing significant economic value to simple solutions to health that do not yeild a large bottom line profit, and so secure national well being and productivity in the widest human sense.

I just hope we manage it before we follow the way of other successful species who destroy their habitat.

Robert Andrew Brown said...


Thank you for sharing that powerful information and the dry pan, amusing way in which such a stark message was delivered

Miki said...

Weston Price, in NAPD, compares micro-nutrients in diets of Traditional groups to a typical American diet. Coppers for some reason, is only compared to the Eskimo diet and found to be 1.8 higher in Alaskan Eskimo diet and 1.2 higher in Canadian Eskimos.

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Unknown said...

Could this be a primary reason that chocolate has been shown to be heart healthy? It's a decent source of copper.

Robert Andrew Brown said...


Please show this to your Professor.

Perfusion of intact skin by a saline solution of bis(glycinato) copper(II).


Metals and the skin: topical effects and systemic absorption
By Richard H. Guy

Page 182


A said...

To your "Blood copper level correlates strongly with the marker of inflammation C-reactive protein (CRP) in humans" I wonder if the relationship is something akin to iron in response to, for example, parasitic infection. Because parasites rely on blood iron, the body ingeniously sequesters it, as part of the defensive mechanism. Perhaps copper plays a similar, if inverse role. If inflammation is high, kick the copper out of the tissues so that it's not oxidizing there. Just an idea.

Mary Joy said...

Very informative post! I learned so much from your post about heart disease. Keep posting.

Unknown said...

Hi Stephan

This is not related to this post, sorry.
Refined wheat flour is often implicated as a possible culprit behind the obesity, diabetes and heart disease epidemic. These diseases, however, gained prevalence during the 20th century with an explosive increase over the past 60 years or so. In North America we began eating copious amounts of white flour centuries before this epidemic took place. How, then, does it make sense to place such blame on white flour. I might be wrong here. I think I read somewhere that we didn't start refining wheat flour extensively until the industrial revolution took place. That would explain it, if that's the case.

Robert Andrew Brown said...


This is what Sir Robert McCarrison had to say about wheat in the 1920s

I apologise for posting it whole but think it is important given the current discussions on wheat.

It does appear that unrefined wheat as part of a wide nutrient dense diet was not detrimental to health in the 1920s.

But modern wheat varieties are less nutrient dense, and soil appears mineral depleted, and fertilisers reduce nutrient density, so wheat is not what it was, and that is before we refine it.

And McCarrison flagged up the problems with white flour 80 years ago.

Health concerns on vitamin C deficiencies and smoking took a while to gain wider acceptance, maybe 100 years, so there is hope yet for an acceptance that removing most of the nutrients before eating food is not the smartest of moves (-:


"Another example of much the same sort is that of stone-in-the-bladder which is brought about in rats by ill-balanced diets containing much oatmeal, or whole-wheat flour. To avoid 'stone' the excess of these cereals must be compensated for by the consumption of appropriate amounts of milk. Those most excellent foods, oatmeal and whole-wheat flour -- the staple articles of diet of such vigorous races as the Scots and the Sikhs -- may likewise prove harmful, by causing disturbance in the normal processes of calcification, when, but only when, the diets containing them are poor in vitamin D.

These cereals are not in themselves complete foods; a fact of which the races using them as staple articles of diet are not wholly in ignorance: the Sikh does not attempt to subsist on atta (whole-wheat flour) alone, nor the Scot on oatmeal. Any ill effect which these two foods may exercise is due to the failure suitably to combine them with other food materials which compensate for their defects. They are not to be condemned nor to be displaced from their prominent place in the dietaries of mankind for this reason. As well might we condemn the perfectly good fuel, petrol, for the over-heating of the engines of our cars when we fail to supply them with sufficient oil, as condemn the excellent wheat and oats when we fail to consume with them sufficient quantities of milk or other vitamin-rich foods, which are required by the human machine for its smooth and efficient running.

Robert Andrew Brown said...


Part 2

"The same kind of misunderstanding surrounds the controversy which periodically rages over the relative values of white bread and bread made from whole-wheat flour. Both are excellent foods though neither is a complete food; and since man requires a certain amount of suitable protein, of mineral salts and of vitamins as well as of carbohydrates, the superiority of the one bread over the other, as the staple article of diet, lies in the extent to which it excels as a source of these essentials. Seeing, therefore, that white bread is notably more deficient in suitable protein, in vitamins (A, B and E) and in certain essential salts than bread made from whole-wheat flour or, indeed, than any other single food entering into the dietaries of western peoples (with the exception of sugars, starches, and fats which are marketed in the pure state) (McCollum), it is by this much the poorer foundation upon which to build a well-balanced diet. Those who can afford to build upon it, and who possess the requisite knowledge to build wisely, have little need to fear nutritional ailments, though their building is improvident, while those who cannot -- and there are millions of such -- are in grave danger of disease. Next, then, in importance to the quality of the various ingredients of our food is their right combination.

Of all the constituents of food on which normal health is dependent, vitamins are the most remarkable. We know neither what they are nor yet how much of them we need, though knowing that normal metabolism is impossible without them. We are accustomed to think of them in such infinitesimal terms that we have come to believe that the amounts we need of them are almost imponderable. I do not know whether they are ponderable or not, nor whether science will ultimately succeed in encompassing them all within chemical formulae; but I do know that for optimum well-being we need much more of them than is generally supposed.

At all events, races like the Sikhs, whose physical development and vigour are equal to those of any race of mankind, and superior to many, consume these substances in large quantities as compared with races whose physique is poor. I find that for rats the well-balanced, vitamin-rich diet of the Sikhs is superior to any synthetic diet I can devise and to which vitamins in the form of yeast and cod-liver oil are added. I do not believe that human beings can have too much vitamins when they are taken in the form in which Nature provides them in well-balanced combinations of unsophisticated food materials."

Jonathan said...

Two fascinating articles in the NY Times on zinc-induced copper deficiency:

Mystery illness solved

Killed by the zinc in Super Poligrip

Gretchen said...

The effects of copper can differ in different species. Grain for cattle includes a copper supplement. If you feed sheep the same copper-supplemented grain, they may suddenly drop dead from copper poisoning. It builds up in the liver and then they get a copper dump and their red blood cells lyse.

For details, see http://www.sheepandgoat.com/articles/coppertox.html

However, the sheep do need some copper. As with so much in life, it's the balance that is important, and animals living wild seem to accomplish this, but when we stuff them with supplements, we can throw things out of balance.

The same is true of selenium. In the west, where soils have a lot of selenium, sheep can die from selenium poisoning. But in the northeast, where soils are slenium-poor, lambs can die from selenium deficiency, called white muscle disease.

Neonomide said...

This copper thing is interesting and I've read about it before. Definitely one topic to look out out in future.

Yet I'm very skeptical that eating more liver is the solution.

A 2008 Cochrane review found vitamin A supplements increased total mortality by 16%, perhaps through its antagonism of vitamin D.


Even more alarming is what happened in a recent Norwegian diet study on heart patients who already HAD an infarction. Who ate more liver, had a significantly elevated risk of having another infarction (CI 0.99-1.97):


Does anyone have evidence that eating liver is healthy at all in terms of endpoints ?

Stephan Guyenet said...

Hi Neonomide,

I took a look at the study. Two points:

1- The liver result wasn't statistically significant.

2- Cod liver oil and fatty fish consumption were associated with a 2-fold reduction in heart attack risk.

I don't think this study supports the idea that liver and/or vitamin A are harmful.

Mavis said...

Thanks for this, Stephan - copper is something I hadn't thought about in years, and I've always been sort of confused about it, since I've seen warnings not to get too much and about the zinc-copper interference.

I wish the top source weren't calf's liver, though! Or that I liked calf's liver. I gave it a try again last night - ick, but half of my family members like it, so I'll keep making it for them.

Time to cook up some crimini mushrooms.

Top sources of copper:


I remember reading somewhere in the mid-80's about copper-deficient pigs developing enlarged hearts. (When I was but a tender lass of 19 in my first bloom as a health info nut.) I also remember reading about pigs developing enlarged hearts on fructose. This was just in time for me. I had read about the dangers of sugar, but that fructose was a "safe" sweetener, and was about to get me some.

And, for people looking for high-magnesium foods, per Stephan's previous post:


Mavis said...
This comment has been removed by the author.
dextery said...


For the yuck factor:
Try thin sliced calf liver pan fried in coconut oil and butter with a little dried thyme and dried basil cook rare.

Got me past the yuck! and actually I really like it now.

Mavis said...

Another source of info on copper --

This is from a list of foods to *avoid* for people with Wilson's disease. (I knew someone who died quite suddenly and quite young from undiagnosed Wilson's disease.) People with this disease can't process copper properly.

For those seeking to increase copper, just reverse the instructions.


Mavis said...

One more comment re: copper sources.

Black strap molasses is also a good source of copper. It also contains a lot of chromium, which may help negate blood sugar rises from the sugar in the molasses. It's a good source of iron and calcium. A reader was concerned about manganese - it does contain a lot of that, too. And this write-up says that manganese, like copper also helps the body make superoxide dismutase.


Robert Andrew Brown said...


I cannot re-find what ever it was I read, that said copper did cross the skin in relatively small amounts, but here is trial that from the summary seems to confirm copper can cross the skin and end up in the wider body.


Examination of the cutaneous absorption of copper after the use of copper-containing ointments.

"an increase of copper in serum and scalp hair and a decrease in urine were found in the study period. "

Sally said...

Thanks all for the comments on copper braclet thing, this is a great read. Love what you all have to say, great participation.

Sally said...

I hate liver too but was tought when I was a kid in school how to make it so liver haters will enjoy it, or not mind it too badly. Not sure how it works with calf liver, works with adult beef liver tho.
in a large baking pan, add tomato sauce aa bottom layer, then shredded mozza cheese, then cooked liver after it is cooked in frying pan as most cook it. add more tomato sauce and another layer of mozza and bake for about two or three hours at 300 degrees or so. The cheese and tomato sauce blends for flavour and the tomato takes some of the liver taste away.
Made my dad eat it, he was not even messed up later when we told him it was liver but he did kind of think it was. He said he would do it again for a small price and he did.

Sally said...

Sorry,,,, cook with foil cover on pan.
Lemme know if anyone tries this and it works.

Sally said...

Oysters? yuk. why is the good stuff found in foods I hate??? haha

Whats the next best food to find copper in?

Mavis said...

anitspirit -

In looking this up (but don't have time to find the link right now), I found research on copper absorption that stated that although copper from vegetable sources is less bioavailable because of phytates, those on a vegetarian diet have better copper status because their diet contains more copper.
I'm not advocating a vegetarian diet, but I think this shows that vegetable sources are a viable option. Probably, the non-vegetarian diet was the typical SAD, not rich in organ meats - or shellfish.

Sally - I have to agree with you. Some people, like my husband, love organ meats and shellfish. I don't. You'd think if this stuff is so good for you, everyone would love it as much as chocolate.

(Chocolate does have a lot of copper, but you have to watch the fructose in it, because that can deplete you of copper.)

Miki said...

Just thought I'd let you know that I have posted a Hebrew translation of this post in my blog.
This is the third or fourth post of yours I have translated.
I always link to original post of course/
P.S Heard your interview - super!

Stephan Guyenet said...

Hi Miki,

Very cool, thanks.

Healthtec Software said...

This research study must be widely discussed and the information spread...not everyone knows about it.And those struggling with the problem must be enlightened.

Medical Billing Software

Unknown said...

Nice Post! Now a days We intake, Copper is low in the diet so we are closely associated with heart disease risk. So we have to increase the level of copper in our diet to reduce the risk of Cardiovascular Disease.

Anonymous said...

Interesting stuff - and yet another J curve, copper in excess is surprisingly toxic. Likewise for chromium, yet both are essential in the right amount.

Luis said...

I have some health problems that I associated with a copper deficiency. My blood markers and hair levels where also low, so this supported my conclusion. However, supplementing with 3 mg copper/day made me feel depressed and also caused an immense weight gain probably by increasing MAO and VEGF, respectively. Obviously, supplements are not the way to go here. So it's probably best to get it from food. Eat your liver !

Anonymous said...

Dr Wallach has been talking about copper deficiency causing:
grey hair, varicose veins, spider veins, mitral valve prolapse for 40 years.

this is great study to back this up.

ProfessorEd said...

Just to update,there is now evidence that copper contributes to Alzheimer's.See http://www.sciencedaily.com/releases/2013/08/130819171636.htm, while another study suggests copper is protective http://www.sciencedaily.com/releases/2013/02/130217083905.htm and http://www.sciencedaily.com/releases/2009/10/091008133457.htm.

It would be nice to see good quality studies to resolve this, possibly examining area with radically different amount of copper in the soil and water.

Of course, it is possible that copper protects against heart disease while promoting Alzheimer's.Human's would probably evolve copper conserving mechanisms because Alzheimer's hits at old ages where it probably has little effect on the number of descendants left, while heart disease in Middle Age could reduce the number of descendants.

Edward Miller

P1 said...

Stephan, do you take any position on supplementing copper / zinc versus getting them from food?

Unknown said...

Hi there, I have a problem facing beef liver, can I get sufficient copper from chicken liver instead? Thanks.

Anonymous said...

Could varicose veins also be a symptom of copper deficiency? If copper is needed for collagen support and structural stability, I bet varicosity is a sign of copper deficiency. Did Klevay study and remark about this?

Unknown said...

Excellent article, now I understand, why Copper wire is used as leads, for ICDs, in Cardiovascular procedures.

Unknown said...

What about people that have pyroluria which causes a deficiency of zinc and B6?
I wonder if they have too much copper? Anyone read anything about this?