An article worth definately worth checking out:
Click here to read: "Do We Really Know What Makes Us Healthy?:" The New York Times
The opening section:
September 16, 2007
Do We Really Know What Makes Us Healthy?
By GARY TAUBES
Once upon a time, women took estrogen only to relieve the hot flashes, sweating, vaginal dryness and the other discomforting symptoms of menopause. In the late 1960s, thanks in part to the efforts of Robert Wilson, a Brooklyn gynecologist, and his 1966 best seller, “Feminine Forever,” this began to change, and estrogen therapy evolved into a long-term remedy for the chronic ills of aging. Menopause, Wilson argued, was not a natural age-related condition; it was an illness, akin to diabetes or kidney failure, and one that could be treated by taking estrogen to replace the hormones that a woman’s ovaries secreted in ever diminishing amounts. With this argument estrogen evolved into hormone-replacement therapy, or H.R.T., as it came to be called, and became one of the most popular prescription drug treatments in America.
By the mid-1990s, the American Heart Association, the American College of Physicians and the American College of Obstetricians and Gynecologists had all concluded that the beneficial effects of H.R.T. were sufficiently well established that it could be recommended to older women as a means of warding off heart disease and osteoporosis. By 2001, 15 million women were filling H.R.T. prescriptions annually; perhaps 5 million were older women, taking the drug solely with the expectation that it would allow them to lead a longer and healthier life. A year later, the tide would turn. In the summer of 2002, estrogen therapy was exposed as a hazard to health rather than a benefit, and its story became what Jerry Avorn, a Harvard epidemiologist, has called the “estrogen debacle” and a “case study waiting to be written” on the elusive search for truth in medicine.
Many explanations have been offered to make sense of the here-today-gone-tomorrow nature of medical wisdom — what we are advised with confidence one year is reversed the next — but the simplest one is that it is the natural rhythm of science. An observation leads to a hypothesis. The hypothesis (last year’s advice) is tested, and it fails this year’s test, which is always the most likely outcome in any scientific endeavor. There are, after all, an infinite number of wrong hypotheses for every right one, and so the odds are always against any particular hypothesis being true, no matter how obvious or vitally important it might seem.
In the case of H.R.T., as with most issues of diet, lifestyle and disease, the hypotheses begin their transformation into public-health recommendations only after they’ve received the requisite support from a field of research known as epidemiology. This science evolved over the last 250 years to make sense of epidemics — hence the name — and infectious diseases. Since the 1950s, it has been used to identify, or at least to try to identify, the causes of the common chronic diseases that befall us, particularly heart disease and cancer. In the process, the perception of what epidemiologic research can legitimately accomplish — by the public, the press and perhaps by many epidemiologists themselves — may have run far ahead of the reality. The case of hormone-replacement therapy for post-menopausal women is just one of the cautionary tales in the annals of epidemiology. It’s a particularly glaring example of the difficulties of trying to establish reliable knowledge in any scientific field with research tools that themselves may be unreliable.
What was considered true about estrogen therapy in the 1960s and is still the case today is that it is an effective treatment for menopausal symptoms. Take H.R.T. for a few menopausal years and it’s extremely unlikely that any harm will come from it. The uncertainty involves the lifelong risks and benefits should a woman choose to continue taking H.R.T. long past menopause. In 1985, the Nurses’ Health Study run out of the Harvard Medical School and the Harvard School of Public Health reported that women taking estrogen had only a third as many heart attacks as women who had never taken the drug. This appeared to confirm the belief that women were protected from heart attacks until they passed through menopause and that it was estrogen that bestowed that protection, and this became the basis of the therapeutic wisdom for the next 17 years.
Faith in the protective powers of estrogen began to erode in 1998, when a clinical trial called HERS, for Heart and Estrogen-progestin Replacement Study, concluded that estrogen therapy increased, rather than decreased, the likelihood that women who already had heart disease would suffer a heart attack. It evaporated entirely in July 2002, when a second trial, the Women’s Health Initiative, or W.H.I., concluded that H.R.T. constituted a potential health risk for all postmenopausal women. While it might protect them against osteoporosis and perhaps colorectal cancer, these benefits would be outweighed by increased risks of heart disease, stroke, blood clots, breast cancer and perhaps even dementia. And that was the final word. Or at least it was until the June 21 issue of The New England Journal of Medicine. Now the idea is that hormone-replacement therapy may indeed protect women against heart disease if they begin taking it during menopause, but it is still decidedly deleterious for those women who begin later in life.
This latest variation does come with a caveat, however, which could have been made at any point in this history. While it is easy to find authority figures in medicine and public health who will argue that today’s version of H.R.T. wisdom is assuredly the correct one, it’s equally easy to find authorities who will say that surely we don’t know. The one thing on which they will all agree is that the kind of experimental trial necessary to determine the truth would be excessively expensive and time-consuming and so will almost assuredly never happen. Meanwhile, the question of how many women may have died prematurely or suffered strokes or breast cancer because they were taking a pill that their physicians had prescribed to protect them against heart disease lingers unanswered. A reasonable estimate would be tens of thousands.
The Flip-Flop Rhythm of Science
...
A Poor Track Record of Prevention
...
Science vs. the Public Health
...
The Bias of Healthy Users
...
The Bias of Compliance
...
How Doctors Confound the Science
...
H.R.T. and the Plausibility Problem
...
What to Believe?
...
Gary Taubes is the author of the forthcoming book “Good Calories, Bad Calories: Challenging the Conventional Wisdom on Diet, Weight Control and Disease.”
Take care.
P.S. For those that may not have had an opportunity yet, those interested in hormone replacement should probably check out the webcast referred to in this post from The Endocrine Society where some of the most highly respected individuals in the field of aging w/respect to the endocrine system present research that suggests HGH supplementation alone has no benefit -- they additionally report on the combination of testosterone and HGH -- this should be a "must see for" competitive athletes and individuals interested in delayed aging through supplementation. What is surprising to find out that GH supplementation does not increase muscle mass -- it seems to only increase water-mass.
Peace.
Edited by adam_kamil, 17 September 2007 - 12:31 AM.
