Wednesday, March 26, 2008

Autism and vaccine?

Whether children should be vaccinated is a hot topic on public forums, such as There's a possibility that children with certain rare disease such as scimitar syndrome should not be vaccinated the same way as normal children are (Ref: But it's probably hard to argue that vaccination should be banned altogether.

Now here's something even stronger against this medical practice, a case where the plaintiff claims autism was aggravated by vaccination. ("On March 6, a federal court granted compensation to a Georgia girl because she developed autism-like symptoms after receiving childhood vaccines in 2000. Officials did not say the vaccines caused autism; rather, they concluded the vaccines aggravated a preexisting condition." Interestingly, the Medscape poll shows that most medical professionals think the ruling is wrong, and physicians are even stronger than nurses in thinking this way, pharmacists in the middle. (Source) Looks like the more knowledge you have, the more likely you'll laugh at the connection.

More news

Wednesday, March 19, 2008

Health Risk of Vitamine E Supplements

Supplemental Vitamin E May Increase Heart Failure Risk

WHS: Women's Heath Study -- Aspirin and Vitamin E for the Primary Prevention of Cardiovascular Disease
qualified success for aspirin in cardioprevention, but no benefit associated with the use of vitamin E.

Meta-analysis Results Suggest High-Dose Vitamin E Increases All-Cause Mortality
"At 400 IUs, which is the most common marketed dose, the risk of dying is about 10% higher than risk among people not taking the vitamin."
Dr.Gibbons, who served as chair of the scientific program committee at the meeting, said he has been urging his patients to stop taking vitamin E for years. Dr. Gibbons said that cardiovascular disease prevention guidelines from "vitamin E is ‘not recommended'. It doesn't get clearer than that — don't take it."

Dr. Miller said there are several theories about why vitamin E increases risk. One theory is that it increases bleeding risk, which would increase the risk of hemorrhagic stroke, while another theory suggests that at high doses vitamin E stops working like an antioxidant that mops up free radicals that attack cells that line blood vessels and instead becomes a prooxidant and actually promotes the production of free radicals.

Still another scenario suggests that high-doses of vitamin E tend to destroy other fat-soluble antioxidants, which disrupts the body's natural antioxidant protection system.

Antioxidant Vitamins May Increase Mortality

March 1, 2007 — The largest analysis of data on antioxidant vitamins ever conducted has shown that beta-carotene, vitamin A, and vitamin E probably increase mortality. Two other antioxidant substances — vitamin C and selenium — had no effect on mortality.

"Vitamin A and beta-carotene seem to have a dose-related effect, with mortality increasing as doses increase, whereas vitamin E does not appear to have a dose-related effect, with all doses associated with increased mortality."

antioxidant vitamins could actually also have prooxidant effects. "We don't know exactly how they are doing harm but rather than preventing cardiovascular disease and cancer, they actually seem to be accelerating these conditions."

Multivitamins Do Not Reduce Risk for Lung Cancer, and Vitamin E May Raise It

February 29, 2008 — The long-term use of supplemental multivitamins does not reduce the risk of developing lung cancer, and high doses of vitamin E may even raise the risk, particularly in smokers.
Although consuming higher amounts of fruits and vegetables can reduce the risk for lung cancer, multivitamins and supplements have generally not demonstrated a benefit in reducing this risk.

Wednesday, March 12, 2008

"Dressed to Kill" and Breast Cancer

The book "Dressed to Kill" was published in 2005 and I was not aware of it till a few days ago. I haven't read it but read some comments and related articles about the same topic, relationship between breast cancer and wearing bras. There're a couple of comments I want to make. Briefly,

1. The relationship is unproven according to American Cancer Society's research (also this). Then how is any study scientific? One of the most compelling review of Sydney Ross Singer et al.'s book is by D. Pilipovich (Kapaau, HI United States). There may be some medical hypotheses that can't be or can't easily be studied by single- or double-blind methods. If ACS does not think this is one of them, then there should be a panel of experts that organize such a study. Singer's study may be too simplistic, not excluding too many confounding factors. But if the cohort number is large enough, it doesn't really matter, although the explanation for the observed relationship may be questionable. This reminds me of some ever-lasting debate in relational databases, such as Oracle. Should one rebuild a table's index or not? In spite of experts' caution, if you rebuild it and it improves performance and it doesn't realistically cause downtime or problem either now or in the near future, do it. By the same token, if a survey of a large number of respondents corroborates the "rumor", give the rumor credit. Even though the theory behind the rumor given by the researchers (Singer and Grismaijer here) is not sufficiently substantiated, the survey result is hard fact and cannot be dismissed unless you find flaws in the survey itself. (I haven't read the book. The theory of lymphatic flow restriction sounds plausible but I wonder why they pick the lymphatic, not for instance blood flow.)

2. Chinese women living in cities generally wear tighter clothing, and possibly tighter bras, and yet have less common occurrences of breast cancer than American women. Do eating more tofu, more exercise (walking and biking) and possibly less smoking explain the difference?

Other articles supporting Singer et al.'s claim:
Bras And Breast Cancer
Health After 40
Bras and Breast Cancer