Health Risks Induced By Taking Vitamins & Dietary Supplements

Timble2

Timble2

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Actually this is fairly academic reaseach in mice research, but it makes a good health scare story.

Vitamins 'increase cholesterol'


Vitamins could actually increase levels of "bad cholesterol", researchers have suggested.

It had been thought that vitamins could protect the heart.

But New York University researchers found vitamins including E, C and beta carotene stop the liver breaking down an early form of bad cholesterol.

Writing in the Journal of Clinical Investigation, the researchers say their findings mean they cannot recommend that people use the vitamins.

Most research tends to suggest that supplementation with antioxidant vitamins, although not beneficial, does not lead to undue harm

Belinda Linden, British Heart Foundation
The vitamins are antioxidants, thought to be beneficial because they attack free radicals, produced when the body fights infection, which inflict damage on the body's tissues.

But studies carried out by the researchers at the university's school of medicine found that antioxidants actually hampered the body's fight against damaging cholesterol.

Normally, liver cells break down a key protein in harmful lipoproteins such as VLDL (very low density lipoprotein) which means they cannot be converted into a form of LDL that can enter the bloodstream.

However, in laboratory tests, the New York researchers found vitamin E, C and beta carotene prevented this process taking place in liver cells.

Further tests in mice and rat livers showed vitamin E prevented this "breakdown" process taking place, meaning the liver destroyed fewer lipoproteins.

Recommendations 'delayed'

Dr Edward Fisher, director of the Lipid Treatment & Research Center at the NYU Medical Center, said: "Our study is the first to document this association between antioxidant vitamins and VLDL cholesterol.

"It does appear that antioxidant vitamins may be potentially harmful for the heart based on their ability to increase the secretion of VLDL in the liver cells and in the mice that we studied."

But he added: "More studies are needed to back up our findings. Until more data becomes available, we can't make any recommendations about whether people should not use these vitamins."

However he said there was evidence from other animal studies that antioxidants could have beneficial effects on other parts of the body, such as protecting the arteries from atherosclerosis and the pancreas and other organs from damage caused by diabetes.

Writing in the journal, Dr Ronald Krauss of Children's Hospital Oakland Research Institute in California, added that, although there was "considerable" evidence for the benefits of antioxidants, "the potential for unintended outcomes of oxidant therapy should serve as a warning against proceeding with such treatment in the absence of clinical-trial evidence of benefit and safety".

Belinda Linden, head of Medical Information at the British Heart Foundation (BHF), told BBC News Online: "Most research tends to suggest that supplementation with antioxidant vitamins, although not beneficial, does not lead to undue harm.

"Before any clear conclusions can be drawn from this study we would await the results of larger randomized controlled clinical trials."
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Hi

(feel free to relocate this if you prefer a more general heading)

also all the usual caveats apply.


source:
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http://www.newscientist.com/news/news.jsp?id=ns99996653

quote:
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High doses of vitamin E may hasten death

15:00 10 November 04

NewScientist.com news service


Taking high doses of vitamin E may increase a person's overall risk of dying in any given year, according to a controversial new analysis. The US researchers say the finding - whose cause is unknown - suggests people should stop taking high doses of the popular supplement.

Earlier studies suggest vitamin E, an antioxidant, has either no effect on mortality rates or lowers the risk of dying from cardiovascular disease. And unlike some other antioxidants, such as vitamin A, vitamin E does not accumulate in the body, potentially becoming toxic.

So US dietary guidelines, while not recommending vitamin E supplements, set a high upper limit of 1500 international units (IU) for their daily intake. Most of the 25% of US adults who take vitamin E supplements take them in large doses - greater than 400 IU per day.

"People take high doses because they think they're going to live longer," says lead author Edgar R. Miller, a physician at Johns Hopkins University School of Medicine in Baltimore, Maryland. "But this research doesn't support that. The death rate is higher with high doses."


Vitamin overdose

Miller says previous studies have been small and not taken dosage into account. But he and his colleagues analysed the dosage levels and death rates of about 136,000 people in 19 clinical trials conducted around the world.

They found that the risk of dying within five years rose by about 5% in the 11 trials with vitamin E doses of at least 400 IU per day. The effect of low-dose supplements, however, lowered the risk of death by less than 1%. The researchers presented their results on Wednesday at a meeting of the American Heart Association in New Orleans, Louisiana. They will publish the work in the Annals of Internal Medicine.

But the authors caution that the results may not apply to the population at large because the high-dose trials were small and their participants tended to have chronic health problems such as heart disease. And because most of the studies did not note the cause of death, the authors say they cannot conclude anything about the underlying mechanism.

But they list four possible causes. Vitamin E is an anti-coagulant, so it may increase the risk of bleeding - which contributes to strokes - in people already taking blood-thinning drugs. Or it could be down to the irregular way people take the supplement. Withdrawal symptoms, such as chest pain, may start when people stop their daily regime.


Rogue compound

Or, say the researchers, vitamin E could become a “turncoat” free radical at high doses, damaging the very proteins and fats it usually protects.

Maret Traber, a nutritionist at Oregon State University in Corvallis, who helped develop the US guidelines for vitamin E, says the turncoat effect has been seen in test tubes. But she notes that the human body may contain enough other antioxidants to neutralise a rogue vitamin compound immediately.


"It's kind of like a little spark flying out of the fireplace - the vitamin E radical never stays around long enough to actually do any damage," Traber told New Scientist.

Finally, the researchers say the type of vitamin E in supplements could displace other antioxidants - including another form of vitamin E found in many foods, disrupting the balance of antioxidant systems.

"It's difficult to figure out why vitamin E should cause death," says Traber, who points out that the new analysis looked only at studies in which people died.

But Stephen Bent, a physician who studies herbal supplements at the University of California in San Francisco, says: "Most of the evidence really hasn't panned out that vitamin E is a very beneficial supplement. So to think that high doses might be harmful is not that surprising."


Maggie McKee

------------------

endquote

Mal F
 
...and never eat a polar bear's liver.

He'll probably get very angry...
 
The Yithian said:
...and never eat a polar bear's liver.

He'll probably get very angry...
Click to expand...
Only if he's using it at the time.

Anyway, that's Vitamin A. And you still shouldn't eat it.
 
No.

This is the FIRST thing you learn about arctic travel.

(The second is not to eat any yellow snow...because...)

I was shocked in one otherwise well researched novel when they did this.

And its best to avoid the liver of other predators too, just to be safe.
 
anome said:
The Yithian said:
...and never eat a polar bear's liver.

He'll probably get very angry...
Click to expand...
Only if he's using it at the time.

Anyway, that's Vitamin A. And you still shouldn't eat it.
Click to expand...

I know - it was a joke...
 
I've stopped believing most of these medical study result announcements because most of them seem to countradict themselves about every 6 -18 months. I have a heavily skeptical attitude toward most of what doctors say. There was an attempt to have vitamins removed from drug store shelves over here, initiated by doctors. The only way you'd be able to get vitamins would be by prescription, costing you an office visit, a trip to the pharmacy, and a jacked up price. :hmph:
 
I am all in favour of that. I was one of those children force fed vitamins instead of having my cabbage cooked `properly` so that it was edible.
 
:D Interesting, I also grew up in a household where all vegetables were canned and cooked to a tasteless mush. Nothing was ever fresh, raw or steamed. Now I eat all my vegetables raw, except for sweet corn.

Now to attempt to get back OT, I take large doses of Vitamin E and C, because they allegedly cut down on the development of Alzheimer's disease, a fear of mine. I heard this news release warning against vitamin E about 6 months after I started it, but I don't believe it. If I kick off in 4 more years, you all will know I was wrong.
 
I never liked vegtables as a child (plus my mother had the notion that potatoes came out of a packet marked `instant mash`...) I ate mostly meat.

I dont think it did me any harm either. But the sort of foods I like now are oriental dishes with lots of vegtables and a little meat. if you gave me western food like as not I would choose all meat and very little veg.

And I `never` peel my potatoes. Lifes too short for peeling spuds
 
Homo Aves said:
And I `never` peel my potatoes. Lifes too short for peeling spuds
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And the skins are the best bit!
 
The Yithian said:
anome said:
The Yithian said:
...and never eat a polar bear's liver.

He'll probably get very angry...
Click to expand...
Only if he's using it at the time.

Anyway, that's Vitamin A. And you still shouldn't eat it.
Click to expand...

I know - it was a joke...
Click to expand...
Sorry...
 
Theres a few threads about vitamins but the stories are specific. Maybe a mod could combine them to create a vitamin thread.

A New Guide To Choosing The Right Vitamin Supplement: Report From Harvard Medical School Separates The Essentials From The Gimmicks
21 Feb 2007

How do you choose a safe and healthy multivitamin? "Vitamins and Minerals: What You Need to Know," a new report from Harvard Medical School, offers the following advice.

-- Look for a seal of approval. Choose products that bear the U.S Pharmacopeia Dietary Supplement Verification Program (USP-DSVP) mark, which indicates that the manufacturer has complied with certain standards.

-- Consider safe levels. All dietary supplements have a "Supplement Facts" label that lists the percentage of the daily value (DV) of each nutrient per serving, as well as the actual amount of each. Multivitamin and multimineral supplements shouldn't exceed 150% of the DV for any nutrient. In fact, for trace minerals, such as iron, fluoride, and zinc, it's safest not to exceed the DV at all.

-- Ignore marketing gimmicks. It doesn't matter whether vitamin C is derived from organic rose hips or synthesized in large batches in a laboratory; your body will use the resulting product similarly. Also, if you're not sensitive to specific ingredients, such as wheat, rice, or lactose, there's no need to pay more for allergen-free products.

-- Don't pay more for unproven extras. There is virtually no evidence that herbs and other nonvitamin ingredients added to supplements -- such as echinacea, bioflavonoids, and ubiquinone (coenzyme Q10) -- are essential for your health.

-- Beware of potentially dangerous interactions. Pay attention to warnings on the label, and tell your doctor and pharmacist what supplements you take.

"Vitamins and Minerals: What you Need to Know" is a 48-page report edited by Meier J. Stampfer, M.D., Ph.D., Professor of Epidemiology and Nutrition, Harvard School of Public Health.

Also included in the report:

-- detailed explanations of each vitamin's and mineral's physiological effects

-- the latest recommendations on each vitamin and mineral

-- current research on how specific vitamins and minerals affect health

-- how to create a healthy and balanced diet

Harvard Health Publications
http://www.health.harvard.edu/


http://www.medicalnewstoday.com/medical ... wsid=63508
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The theory goes that one reason we get more colds in the winter is not that there are more viruses around but that the body is less-equipped to deal with them because of a lack of sunlight and therefore Vitamin D. With all my colleagues snotted up and dropping like flies, I appear to have avoided a cold so far this winter, well a really bad one, I've had a few snuffles but they've not really developed into anything major. I read an article somewhere, dammed if I can find it though, that made the claim that massive doses of Vitamin D enabled the immune system to fight colds better, so I'm trying this out.

At first I was taking Calcium (400mg/50% RDA) and Vit D (2.5ug/50% RDA) tablets (from Tesco); six a day but these made me feel sick so I stopped. I'm now on one Vit D (25ug/500% RDA) tablet a day (from Holland & Barrett), two if I start to feel grotty.

I work in a Hospital Lab and have taken proper medical advice on what taking such high doses could do to me, the Professor of Chemical Pathology raised his eyebrow, proclaimed it to be total bollocks and said I'd piss out any excess, so I'm not too worried!

Am I the only person doing this? I'd be interested to hear from other Vit D abusers out there!
 
I eat fresh fruit and veg every day and feel that this provides enough vitamin c. It also gives me fibre and satisfies my hunger. :D
 
Yup but vit c is what we're normally advised to take for preventing colds. That, and washing our hands before eating so we don't transfer germs to our mouths.
 
The oranges are nice though.

If you sneeze on me once more, you're dead.
 
Ewwww, and I thought the sneezing was bad! :evil:
 
You've just won another bet. haven't you? :?
 
:headbutt: I'm taking Vit D, not C, please read my initial post. I tried the 1000mg Vit C tablets and all it did was give me a weak fizzy drink and bright orange pee. :)
 
A weak fizzy drink and bright orange pee? Bargainous. :D

I'm a believer in the benefits of sunshine and understand about the vit d and sunshine. I also like to have the sun on my face, especially in the winter, to stimulate my pineal gland. Can you tell I'm an old hippy? :lol:

Most dietary supplements in tablet form pass through the body undigested. It's better to help our bodies absorb or manufacture vitamins in a natural way.
 
Yes the pee was a shock first time I can tell you! It looked like Lucozade!
 
markthrone said:
:headbutt: I'm taking Vit D, not C, please read my initial post. I tried the 1000mg Vit C tablets and all it did was give me a weak fizzy drink and bright orange pee. :)
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Wow! Bright orange pee! I've never had that, and I've been a regular user of those 1000 mg orange vitamin C tablets. You must have taken rather a lot to get that result.
 
markthrone said:
Yes the pee was a shock first time I can tell you! It looked like Lucozade!
Click to expand...
but did it t...

no, we're not going there.
 
I started with something cold-like on Sunday, so have taken 50ug yesterday and again today. I'll keep posting on here how I feel from day to day just for the record. I'll only take Vit D, nothing else.

Yesterday I'd rate it as 3 sniffs out of a possible 10, today it's about the same.

[It's not exactly a Clinical Trial is it!]
 
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