Most clinical studies on vitamins flawed by poor methodology

[cronus]

http://oregonstate.edu/ua/ncs/archives/ ... ethodology

Review: Most clinical studies on vitamins flawed by poor methodology

CORVALLIS, Ore. – Most large, clinical trials of vitamin supplements, including some that have concluded they are of no value or even harmful, have a flawed methodology that renders them largely useless in determining the real value of these micronutrients, a new analysis suggests.

Many projects have tried to study nutrients that are naturally available in the human diet the same way they would a powerful prescription drug. This leads to conclusions that have little scientific meaning, even less accuracy and often defy a wealth of other evidence, said Balz Frei, professor and director of the Linus Pauling Institute at Oregon State University, in a new review published in the journal Nutrients.

These flawed findings will persist until the approach to studying micronutrients is changed, Frei said. Such changes are needed to provide better, more scientifically valid information to consumers around the world who often have poor diets, do not meet intake recommendations for many vitamins and minerals, and might greatly benefit from something as simple as a daily multivitamin/mineral supplement.

Needed are new methodologies that accurately measure baseline nutrient levels, provide supplements or dietary changes only to subjects who clearly are inadequate or deficient, and then study the resulting changes in their health. Tests must be done with blood plasma or other measurements to verify that the intervention improved the subjects’ micronutrient status along with biomarkers of health. And other approaches are also needed that better reflect the different ways in which nutrients behave in cell cultures, lab animals and the human body.
The new analysis specifically looked at problems with the historic study of vitamin C, but scientists say many of the observations are more broadly relevant to a wide range of vitamins, micro nutrients and studies.

“One of the obvious problems is that most large, clinical studies of vitamins have been done with groups such as doctors and nurses who are educated, informed, able to afford healthy food and routinely have better dietary standards than the public as a whole,” said Frei, an international expert on vitamin C and antioxidants.

Vitamin or mineral supplements, or an improved diet, will primarily benefit people who are inadequate or deficient to begin with, OSU researchers said. But most modern clinical studies do not do baseline analysis to identify nutritional inadequacies and do not assess whether supplements have remedied those inadequacies. As a result, any clinical conclusion made with such methodology is pretty much useless, they said.

“More than 90 percent of U.S. adults don’t get the required amounts of vitamins D and E for basic health,” Frei said. “More than 40 percent don’t get enough vitamin C, and half aren’t getting enough vitamin A, calcium and magnesium. Smokers, the elderly, people who are obese, ill or injured often have elevated needs for vitamins and minerals.

“It’s fine to tell people to eat better, but it’s foolish to suggest that a multivitamin which costs a nickel a day is a bad idea.”

(continued)

[Xamonas Chegwé]

"Most large, clinical trials of vitamin supplements, including some that have concluded they are of no value or even harmful, have a flawed methodology that renders them largely useless in determining the real value of these micronutrients, a new analysis suggests."

...and most probably including ALL that have concluded that long-term diet supplementation is necessary or beneficial.

The Linus Pauling Institute is largely funded by the National Center for Complementary and Alternative Medicine, an organisation that has come under much criticism for its wooish practices. Here's what Science had to say about them,

"We believe that NCCAM funds proposals of dubious merit; its research agenda is shaped more by politics than by science; and it is structured by its charter in a manner that precludes an independent review of its performance."

I call bullshit on this report.

[cronus]

"Most large, clinical trials of vitamin supplements, including some that have concluded they are of no value or even harmful, have a flawed methodology that renders them largely useless in determining the real value of these micronutrients, a new analysis suggests."

...and most probably including ALL that have concluded that long-term diet supplementation is necessary or beneficial.

The Linus Pauling Institute is largely funded by the National Center for Complementary and Alternative Medicine, an organisation that has come under much criticism for its wooish practices. Here's what Science had to say about them,

"We believe that NCCAM funds proposals of dubious merit; its research agenda is shaped more by politics than by science; and it is structured by its charter in a manner that precludes an independent review of its performance."

I call bullshit on this report.

Even a broken clock is correct twice each day.

[JimC]

It should become part of the 5 part Scottish diet.

Grease, sugar, salt, alcohol and a multi-vitamin pill...

[Trinity]

It would be good, however, to have studies which aren't backed by wooists or mega pharma companies-independent and unbiased trials.

[FBM]

Read up on Linus Pauling's Vitamin C obsession and you'll get the idea. And note that he died of cancer after all those decades of mega-doses of Vit. C.

[Xamonas Chegwé]

Read up on Linus Pauling's Vitamin C obsession and you'll get the idea. And note that he died of cancer after all those decades of mega-doses of Vit. C.

It's amazing how many of these sensationalist headlines reduce to vested interests and one-man crusaders once you do a little digging. My golden rule when reading any "news item" such as this is to look for the company name behind it (there almost always is one) and then do a little googling to see what their agenda is..

[cronus]

Seems a reasonable case that reasonable baselines should be in place other things aside though? Big pharma companies do have a vested interest in 'bad science' if it suits them, also. Seems no harm is being done by looking at the way studies are carried out and checking for good sound objective practice, or the alternative?

[JimC]

It may well be true that vitamin supplements are useful for people in unusual situations, or with extremely poor diets. For example, my wife has a skin which burns incredibly easily, and avoids the sunlight like a vampire. Despite a pretty good diet, she had a vitamin D deficit as a consequence of little sunlight on the skin, and so takes a daily supplement.

However, the vitamin supplement industry sells their product via the spin that everybody needs their product, which is undoubtedly self-serving overkill...

[Xamonas Chegwé]

Seems a reasonable case that reasonable baselines should be in place other things aside though? Big pharma companies do have a vested interest in 'bad science' if it suits them, also. Seems no harm is being done by looking at the way studies are carried out and checking for good sound objective practice, or the alternative?

No one is disputing that. BUT, the key sentence is the one I highlighted.

Most large, clinical trials of vitamin supplements, including some that have concluded they are of no value or even harmful, have a flawed methodology that renders them largely useless in determining the real value of these micronutrients, a new analysis suggests.

It is an extremely well known fact that the majority of vitamin trials are practically useless by dint of the simple fact that they are carried out by companies with a vested interest in selling little pills to gullible gullets and have been designed to prove that that is a good thing!

This article is disingenuous in that it conflates that with the fact that there are always going to be a few inconclusive or badly carried out trials that return opposite findings - and, hey presto!, you have the FACT that all previous vitamin trials are useless and nothing can be determined from them - so you may as well keep taking the pills until we sort this out properly.

This is bollocks!

The facts are as follows:

1. All trials that have shown that taking vitamin supplements are beneficial to those with a reasonable base level of nutrition are flawed.
2. A few trials that have shown the opposite are flawed.

The fact remains that, of those trials that are NOT flawed, ALL have shown that (a) there is no need for any in the civilised world to take vitamin supplements (b) there is no improvement in cancer rates, cancer recovery, disease resistance, etc. among those taking supplements and (c) excessive supplementation can actually be detrimental to health.

These are the facts. Sadly though, these don't help Gillian McKeith get richer. So let's ignore them and take folic acid, star flower and garlic pills 7 times a day!

[cronus]

...clarifying the unusual situations would be in everyone's interest surely, though? Does seem the article sees the need for targeted usage. If studies are showing that fish oil acts as a mood stabiliser, which even valid scientific studies have hinted at, and places like Detroit have very little access to sea-products, then doling out cheap fish-oil caps might be part of the answer for a city in decline?

[Xamonas Chegwé]

...clarifying the unusual situations would be in everyone's interest surely, though? Does seem the article sees the need for targeted usage. If studies are showing that fish oil acts as a mood stabiliser, which even valid scientific studies have hinted at, and places like Detroit have very little access to sea-products, then doling out cheap fish-oil caps might be part of the answer for a city in decline?

No. It may be part of the solution for a dietary supplement industry worried about being in decline - but that's all.

[rainbow]

...clarifying the unusual situations would be in everyone's interest surely, though? Does seem the article sees the need for targeted usage. If studies are showing that fish oil acts as a mood stabiliser, which even valid scientific studies have hinted at, and places like Detroit have very little access to sea-products, then doling out cheap fish-oil caps might be part of the answer for a city in decline?

No. It may be part of the solution for a dietary supplement industry worried about being in decline - but that's all.

If God had meant us to eat vegetables, he would never have given us vitamin pills.

[cronus]

...clarifying the unusual situations would be in everyone's interest surely, though? Does seem the article sees the need for targeted usage. If studies are showing that fish oil acts as a mood stabiliser, which even valid scientific studies have hinted at, and places like Detroit have very little access to sea-products, then doling out cheap fish-oil caps might be part of the answer for a city in decline?

No. It may be part of the solution for a dietary supplement industry worried about being in decline - but that's all.

If God had meant us to eat vegetables, he would never have given us vitamin pills.

Good science should provide the answer - seems to require more than a straightforward meta-study, these vits and herbs and things are manifold, but given that the US has countless medical student types out of work and can print it's way through costs....could be done? Devil makes work for idle hands and some of those bio-hackers could do with real work rather than wiping out part of the human race with some concoction in their garage? Thinking of the big picture gives you a headache I know.

[pErvinalia]

I've just started taking multi-vitamins about 3 weeks ago due to the fact that my diet is horrendous lately. I eat virtually no vegetable matter (although I do eat some fruit while it keeps; and chocolate is technically a vegetable... ). I noticed that wounds were taking a long time to heal. That's definitely improved. I also once got a bit of relief from a crazy muscle twitch that went all waking hours and was driving me insane. The magnesium tablets reduced it after a few days and after a few days more it went away. No diet changes. Possibly a placebo, I guess, but I suspect it actually worked.