Possible Link Between Folic Acid and Breast Cancer Found

[Tab]

This is the stuff they urge you to take when pregnant.

FRIDAY, Dec. 10 (HealthDayNews) -- A British study has found a possible link between taking folic acid supplements late in pregnancy and an increased incidence of breast cancer decades later.

But the researchers themselves state that the finding should be viewed with considerable caution.

"It is quite possible that this is a chance finding," said Dr. Andy R. Ness, a senior lecturer in epidemiology at the University of Bristol, and lead author of the report in the Dec. 11 issue of the British Medical Journal. "What we have found needs to be interpreted very cautiously until there has been further research."
...
Women now are advised to take 400 micrograms a day of folic acid when they plan to become pregnant and continue to do so until the 12th week of pregnancy, but not longer; the birth defects it prevents occur early in pregnancy.
...
The effect was most noticeable among women who took the highest doses.
...
"But the number of cases is very small," Ness said. "We're talking about six or eight cases of breast cancer among almost 500 women over 35 years, when normally we might have expected four deaths. The only thing we can say for certain as a result of this research is that there needs to be further research."
http://story.news.yahoo.com/news?tmpl=story&ncid=1437&e=3&u=/hsn/20041210/hl_hsn/possiblelinkbetweenfolicacidandbreastcancerfound&sid=95864962

[HuckleB]

1. This is very, very preliminary.

Further, the findings discuss consumption of folic acid late in pregnancy, not during the first 12 weeks (and during any period where becoming pregnant may be possible), when it is recommended in order to prevent spina bifida and other neural tube related birth defects. Folic acid supplements are not recommended past the first trimester, as that is when such birth defects develop. Thus, even if this study plays out to show that folic acid consumption late in pregnancy increases the risk of breast cancer, it does not mean that current recommendations are going to change.

[Tab]

2. True, but it might mean changes..

Under the philosophy "more is better", it notes that while people under the recommended dosage were about the same, those who "mega-dosed" ended up with nearly double the cancer rate.

Granted, the sample is small - 3000 patients (decent sample) of which they expected 4 to get cancer, and 6 to 8 got cancer, and those were the ones taking mega-doses, if I read it right. Still small, I would think statistically, but double the expected amount.

As the article notes, it doesn't prove anything, but it highlights a potential problem, warranting more research.

[HuckleB]

3. Exactly. Which means no change in recommendations.

The recs don't call for megadoses for good reason. No one has studied the safety of such doses, while the recs given have shown to prevent neural tube defects. Warnings against megadoses may be made, but they probably should be made regarding all substances. Our bodies need these nutrients, but in moderation, to call forth a cliche.

Unfortunately, what often happens with such headlines is that future mothers simply stop taking the supplement in question. If this gets huge press, I suspect that we will see an increase in the number of spina bifida cases in the coming years, as the science press is terrible at getting the whole story across.

[Tab]

4. I agree

They won't change the recommended daily dose, but they might specifically warn against megadosing.

[baba]

15. I always heard you should take a prenatal throughout pregnancy.

I heard you should take a prenatal vitamin with folic acid and iron throughout the whole pregnancy, not just the first 12 weeks. :shrug:

[CornField]

5. Well, I'll know in a decade or so

I lost a child in 1995 to severe neural tube defects. For each subsequent pregnancy the guidelines of how much folic acid I should take and for how long were increased. I was definitely one of those mega-dosers... and was told to continue past the 12-week mark.

[interupt]

6. How to make a public ass of yourself in a medical journal in 5 easy steps

1. Call yourself an epidemiology lecturer....check
2. Use data from the 1960's because accurate notes on vitamin suppliments were readily available then...check
3. Use a pilot study with an entirely different hypothesis to prove your own stupid hypothesis....check
4. Ignore other people in your own faculty and your own goddam university's advice because, hey you name is going to be published so nyah nyah.....check
5. Call "decades later" a "link" even though you have no fucking idea what these women have done in their lives, and probably just cross referenced death certifictes for verification....check.

ITS JUST THAT EASY!

[TO Kid]

8. Coal companies used that technique

Those were the tactics used by the coal industry to blame smoking for all the respiratory problems suffered by the miners.

[muriel_volestrangler]

9. Or make an ass of yourself on an Internet forum

by misrepresenting the paper.

In women randomised to high doses of supplemental folate, all cause mortality was about a fifth greater, and the risk of deaths attributable to breast cancer was twice as great. This increased risk in deaths attributable to breast cancer is unlikely to be due to competing causes as the number of deaths was small and all cause mortality appeared to be greater. The increase in mortality and in death from breast cancer with high doses of folate could be a chance finding. The number of deaths was small, the confidence intervals were wide, and we had no prespecified hypothesis that taking folate supplements in pregnancy would increase the risk of cancer. As this randomised trial was of high quality, bias and confounding are unlikely explanations for our findings. A recent study indicated that rats fed diets deficient in folate had increased mammary tumorigenesis compared with rats fed diets with sufficient folate, whereas rats fed a high dose folate diet had similar levels of tumorigenesis to deficient rats. Our data are preliminary and these findings require confirmation.

http://bmj.bmjjournals.com/cgi/content/full/329/7479/1375?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&fulltext=folic&searchid=1102694822839_39440&stored_search=&FIRSTINDEX=0&volume=329&issue=7479

[interupt]

10. Thank you for the link...

In all, 3037 women were recruited to the study, and 2928 were randomised. In the placebo group, 1.9% reported that they had not taken their tablets regularly compared with 1.7% in the group taking 0.2 mg folate and 3.2% in the group taking 5 mg. Initial folate concentrations were similar in the three groups. For later folate measurements there was a dose-response relation between dose of folate and folate status. Baseline characteristics of the women in the three treatment groups were comparable.

And the data was compiled in 1967


By the end of September 2002, 210 women had died; 40 deaths were attributable to cardiovascular disease, 112 to cancer, and 31 to breast cancer (table).

As you point out in the comment, this paper then cites another source as an extremely dubious confirmation by using rat studies.

http://carcin.oupjournals.org/cgi/content/abstract/24/5/937?ijkey=661699774a568b6585be0550b3564a0ad9a45323&keytype2=tf_ipsecsha

The researcher was unsure about his own results, and proceeded to be an ass by attracting the attention of the media.

I didn't misrepresent his paper, those who provided comment did.

EDIT: I stand corrected. The researcher didn't make an ass of herself.
Deborah Charles, research assistant1, Andy R Ness, senior lecturer in epidemiology2, Doris Campbell, reader in obstetrics and gynaecology1, George Davey Smith, professor of clinical epidemiology3, Marion H Hall, emeritus professor1


Contributors: DC did the fieldwork and the analysis. AN wrote the first draft. All the authors commented on this and subsequent drafts. AN is guarantor.


So someone tries to get their name up in lights by using their assistants research....

[bloom]

12. well - it would have been in the 60's that the women

would have been taking the folic acid in their pregnancies - where the incidence might show up now.

Or is that what you figured out....

[interupt]

13. I agree

But in the scheme of things...40 years later you might have a 1% chance of cancer if you overdose of folate?

Moral of the study: Dont take too much of one thing. THough I wouldnt call this a study...thats my call.

[amazona]

7. doesn't make sense

Folic acid is recommended to women who drink alcohol because it reduces the risk of breast cancer, which is otherwise slightly elevated in women who drink.

Maybe the huge megadoses -- 10 MILLIGRAMS? -- are responsible or maybe the study is just a bad one.

I would continue taking the 400 micrograms of folic acid.

[SoCalDem]

11. LIFE "causes" cancer

:(

I doubt that there will ever be a single causative agent found, but if you live long enough, and are exposed to a myriad of chemical compounds through ingestion, application or proximity, something's gonna get ya..


Life is a sexually transmitted, terminal condition.

[Dcitizen]

14. Folate may causes 1.5% cancer

but rarely Asian get hit from brown rice.
O8)