Tuesday, January 22, 2008

Just two cups of coffee per day could double risk of miscarriage (?)

Another stupid epidemiological study based on self-reports. There is a common polydrug pattern among drug addicts and where better to find polydrug abusers than in SF? The effect could be due to other drugs also used by caffeine addicts there. Heavy coffee drinking is very common among addicts "coming down"

Drinking two cups of coffee a day during pregnancy can double the risk of miscarriage for expectant mothers, researchers say. A US study has confirmed that high doses of caffeine during pregnancy, from coffee, tea, caffeinated soft drinks or hot chocolate, can increase the risk of losing a baby. Women who consumed 200 mg or more of caffeine per day - equivalent to two or more cups of regular coffee or five cans of cola - had twice the miscarriage risk of women who consumed no caffeine, the study found. Even those who consumed less than 200 mg of caffeine daily had a more than 40 per cent increased risk, the study, published in the American Journal of Obstetrics and Gynecology says.

Caffeine is known to cross through the placenta from mother to the foetus, and is thought to influence cell development and decrease blood flow, causing harm to the developing child. Current guidelines from the Food Standards Agency recommend 300 mg of caffeine a day as the safe upper limit for pregnant women. Experts said the new findings would prompt them to advise women to cut out caffeine altogether, at least for the first 12 weeks of pregnancy.

Miscarriage occurs in about one in six confirmed pregnancies, usually within 12 weeks, when the foetus is especially vulnerable. While previous research showed a link between high caffeine consumption and increased risk of miscarriage and stillbirth, this is the first study to take fully into account morning sickness, which causes many pregnant women to avoid caffeine and cut down their intake.

It examined data on 1,063 pregnant women in San Francisco from October 1996 to October 1998 who did not change their pattern of caffeine consumption during pregnancy. Women in the study were asked about the amount and frequency of their intake of caffeinated beverages. Pregnancy outcomes up to 20 weeks of gestation were determined for all participants.

Overall, 172 of women in the study (16.18 per cent) miscarried. Whereas 264 women reported no consumption of any drinks containing caffeine during pregnancy, 635 women (60 per cent) reported consuming between 0-200 mg of caffeine a day, and 164 women drank 200 mg or more. Other risk factors for miscarriage were also accounted for in the study, which found that miscarriage was associated with consumption of caffeine overall, rather than particular drinks.

DeKun Li, who led the study for Kaiser Permanente, a US health insurance company, said: "This strengthens the association between caffeine and miscarriage risk because it removes speculation that the association was due to reduced caffeine intake by healthy pregnant women. "The main message for pregnant women is that they probably should consider stopping caffeine consumption during pregnancy."

Pat O'Brien, a consultant obstetrician at University College Hospital, London, and spokesman for the Royal College of Obstetricians and Gynaecol-ogists, said: "This is the best evidence we now have on the subject and I will advise patients to avoid caffeine completely, at least for the first 12 weeks of pregnancy. Good studies have shown it may be safer to drink caffeine after that, but no more than 200 mg a day is still to be recommended."



One of the now boringly regular demonstrations that at the deepest level all men are NOT equal. Lupus is pretty nasty so it is good to see some slow progress with it

Polymorphism at the TNF superfamily gene TNFSF4 confers susceptibility to systemic lupus erythematosus

By Deborah S Cunninghame et al.

Systemic lupus erythematosus (SLE) is a multisystem complex autoimmune disease of uncertain etiology (OMIM 152700). Over recent years a genetic component to SLE susceptibility has been established. Recent successes with association studies in SLE have identified genes including IRF5 and FCGR3B. Two tumor necrosis factor (TNF) superfamily members located within intervals showing genetic linkage with SLE are TNFSF4 (also known as OX40L; 1q25), which is expressed on activated antigen-presenting cells (APCs) and vascular endothelial cells, and also its unique receptor, TNFRSF4 (also known as OX40; 1p36), which is primarily expressed on activated CD4+ T cells. TNFSF4 produces a potent co-stimulatory signal for activated CD4+ T cells after engagement of TNFRSF4. Using both a family-based and a case-control study design, we show that the upstream region of TNFSF4 contains a single risk haplotype for SLE, which is correlated with increased expression of both cell-surface TNFSF4 and the TNFSF4 transcript. We hypothesize that increased expression of TNFSF4 predisposes to SLE either by quantitatively augmenting T cell-APC interaction or by influencing the functional consequences of T cell activation via TNFRSF4.

Nature Genetics 40, 83 - 89 (2007)


Just some problems with the "Obesity" war:

1). It tries to impose behavior change on everybody -- when most of those targeted are not obese and hence have no reason to change their behaviour. It is a form of punishing the innocent and the guilty alike. (It is also typical of Leftist thinking: Scorning the individual and capable of dealing with large groups only).

2). The longevity research all leads to the conclusion that it is people of MIDDLING weight who live longest -- not slim people. So the "epidemic" of obesity is in fact largely an "epidemic" of living longer.

3). It is total calorie intake that makes you fat -- not where you get your calories. Policies that attack only the source of the calories (e.g. "junk food") without addressing total calorie intake are hence pissing into the wind. People involuntarily deprived of their preferred calorie intake from one source are highly likely to seek and find their calories elsewhere.

4). So-called junk food is perfectly nutritious. A big Mac meal comprises meat, bread, salad and potatoes -- which is a mainstream Western diet. If that is bad then we are all in big trouble.

5). Food warriors demonize salt and fat. But we need a daily salt intake to counter salt-loss through perspiration and the research shows that people on salt-restricted diets die SOONER. And Eskimos eat huge amounts of fat with no apparent ill-effects. And the average home-cooked roast dinner has LOTS of fat. Will we ban roast dinners?

6). The foods restricted are often no more calorific than those permitted -- such as milk and fruit-juice drinks.

7). Tendency to weight is mostly genetic and is therefore not readily susceptible to voluntary behaviour change.

8). And when are we going to ban cheese? Cheese is a concentrated calorie bomb and has lots of that wicked animal fat in it too. Wouldn't we all be better off without it? And what about butter and margarine? They are just about pure fat. Surely they should be treated as contraband in kids' lunchboxes! [/sarcasm].

9). And how odd it is that we never hear of the huge American study which showed that women who eat lots of veggies have an INCREASED risk of stomach cancer? So the official recommendation to eat five lots of veggies every day might just be creating lots of cancer for the future! It's as plausible (i.e. not very) as all the other dietary "wisdom" we read about fat etc.

10). And will "this generation of Western children be the first in history to lead shorter lives than their parents did"? This is another anti-fat scare that emanates from a much-cited editorial in a prominent medical journal that said so. Yet this editorial offered no statistical basis for its opinion -- an opinion that flies directly in the face of the available evidence.

Even statistical correlations far stronger than anything found in medical research may disappear if more data is used. A remarkable example from Sociology:
"The modern literature on hate crimes began with a remarkable 1933 book by Arthur Raper titled The Tragedy of Lynching. Raper assembled data on the number of lynchings each year in the South and on the price of an acre's yield of cotton. He calculated the correlation coefficient between the two series at -0.532. In other words, when the economy was doing well, the number of lynchings was lower.... In 2001, Donald Green, Laurence McFalls, and Jennifer Smith published a paper that demolished the alleged connection between economic conditions and lynchings in Raper's data. Raper had the misfortune of stopping his analysis in 1929. After the Great Depression hit, the price of cotton plummeted and economic conditions deteriorated, yet lynchings continued to fall. The correlation disappeared altogether when more years of data were added."
So we must be sure to base our conclusions on ALL the data. But in medical research, data selectivity and the "overlooking" of discordant research findings is epidemic.

"What we should be doing is monitoring children from birth so we can detect any deviations from the norm at an early stage and action can be taken". Who said that? Joe Stalin? Adolf Hitler? Orwell's "Big Brother"? The Spanish Inquisition? Generalissimo Francisco Franco Bahamonde? None of those. It was Dr Colin Waine, chairman of Britain's National Obesity Forum. What a fine fellow!


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