According to the Mayo Clinic website, lower levels of cholesterol are better. For total cholesterol, says the Mayo Clinic, below 5.2 mmol/L (= 200 mg/dL) is “desirable”. A level from 5.2 to 6.2 mmol/L is “borderline high”, and above 6.2 mmol/L (= 240 mg/dL) is “high”.
A 2011 study from Norway, based on 500,000 person-years of observation, found drastically different results. For both men and women, the lowest levels of total cholesterol (below 5.0 mmol/L) were associated with the most death. For men, the best level was intermediate — what the Mayo Clinic calls “borderline high”. For women, the safest levels were the highest.
If high cholesterol causes heart disease, as we are so often told, the pattern for women makes no sense. For a long time, experts have told us to limit egg consumption because eggs are high in cholesterol. However, a new study shows that egg consumption has no association with heart disease risk.
Via Malcolm Kendrick. I also like his post about whether statins cause muscle pain.
A draft article by Spyros Makridakis about blood pressure and iatrogenics takes issue with the statement that “The treatment of hypertension has been one of medicine’s major successes of the past half-century.” Over the last half-century, the article says, the death rate for people with high blood pressure decreased by almost exactly the same amount as the death rate for people without high blood pressure. Apparently “one of medicine’s major successes” is a case where the health benefit no more than equaled the health cost — leaving aside what the treatment cost in time and money.
Because very high blood pressure (systolic > 180 mm Hg) is quite dangerous and blood pressure drugs really work, this is a surprising outcome. Makridakis points out that doctors start treating high blood pressure when it rises above systolic = 140 mm Hg, a point when there is little or no increase in death rate. This article tells doctors to immediately prescribe drugs when systolic blood pressure is above 160. Yet death rate clearly increases only when systolic blood pressure is above 180. Makridakis concludes (as do I) that blood pressure drugs have significant health costs as well as benefits. The drugs are so often prescribed when they do no good and the costs are so high that the overall health costs of blood pressure treatment have managed to be as high as the overall benefits. Even when handed a relatively easy-to-measure problem (high blood pressure) and a relatively simple solution (blood pressure drugs), our health care system managed to achieve no clear gain. If this is “one of medicine’s major successes”, medicine is in bad shape.
The last paragraph of Makridakis’s article makes a surprising statement: “We strongly believe that medicine is extremely useful.” It does not explain this belief, which is contradicted by the rest of the article. I was puzzled. I wrote to the author: Continue reading “Hard to Say Whether Medicine Does More Good Than Harm”
Two thought-provoking paragraphs from Matt Ridley:
From ancient Egypt to modern North Korea, always and everywhere, economic planning and control have caused stagnation; from ancient Phoenicia to modern Vietnam, economic liberation has caused prosperity. In the 1960s, Sir John Cowperthwaite, the financial secretary of Hong Kong, refused all instruction from his LSE-schooled masters in London to plan, regulate and manage the economy of his poor and refugee-overwhelmed island. Set merchants free to do what merchants can, was his philosophy. Today Hong Kong has higher per capita income than Britain.
In July 1948 Ludwig Erhard, director of West Germany’s economic council, abolished food rationing and ended all price controls on his own initiative. General Lucius Clay, military governor of the US zone, called him and said: “My advisers tell me what you have done is a terrible mistake. What do you say to that?” Erhard replied: “Herr General, pay no attention to them! My advisers tell me the same thing.” The German economic miracle was born that day; Britain kept rationing for six more years.
This is standard libertarianism. I like the stories but I don’t agree with the interpretation. I don’t think it is “economic planning and control” that causes stagnation in these examples. I believe it is expertise — more precisely, rent-seeking experts who know too little and extract too much rent. There are libertarian experts, too. They too are capable of doing immense damage (e.g., Alan Greenspan), contradicting Ridley’s view that “economic liberation” always causes prosperity. In both of Ridley’s examples, the experts give advice that empowers the experts. In the first example, Cowperthwaite is told by “LSE-schooled” economists to “plan, regulate and manage the economy.” All that planning, regulation and management require expertise, in particular expertise similar to that of the experts who advised it. Which you cannot buy — you have to rent it. You must pay the experts year after year after year to plan, regulate, and manage. Because the advice must empower the experts, there is a strong bias away from truth. That is the fundamental problem. Continue reading “Rent-Seeking Experts”
New York magazine commenters are usually smart and well-informed. Which is why this comment, on an article about “the forgotten victim”, Nancy Lanza, the shooter’s mother, stands out:
They say money cannot buy happiness [Adam’s father is apparently rich], but when dealing with someone with a mental illness, it can go a long way toward paying to fix unhappiness — it can pay for good doctors, proper medication [emphasis added], care-givers/guardians, all the tools required to secure a property and keep the “patient” safe, AND giving the mentally ill person his ideal living situation, limiting the snits and tantrums that can lead to real anger, which, in turn can lead to acting out.
No doubt this particular commenter is smart and well-informed. Which makes the fact that he or she is perfectly sure that “proper medication” exists so scary, at least if this person had any control over me or anyone who mattered to me. It reminds me of people who think that if you’re fat all you have to do is eat less.
This fascinating blog post by Josh Mittledorf points out that antioxidants, once believed to reduce aging by reducing oxidative damage, have turned out to have the opposite effect. By reducing a hormetic effect, they make things worse. I’m a friend of Bruce Ames, one of main proponents of the free radical theory of aging. I’ve heard him talk about it a dozen times. The turning point — the beginning of the realization that this might be wrong — was this 1994 study, which found that beta-carotene, a potent antioxidant, increased mortality. Bruce did not have a good explanation for the counter-theoretical result. However, Mittledorf doesn’t mention an important fact which doesn’t fit his picture. Selenium, a potent antioxidant, also powerfully reduces cancer. Don’t stop taking selenium.
I also like this theoretical paper by Mittledorf about why aging evolved (turning off certain genes reduces aging) and how its evolution — not easily explained by conventional evolutionary ideas — is part of a range of phenomena that the conventional ideas cannot explain. One reason, maybe the main reason, that aging is adaptive is very Jane Jacobsian: it makes the community more flexible. Less likely to repeat old ways of doing things.
Thanks to Ashish Mukarji.
Health experts call bacteria “good” and “bad”. Bad bacteria make us sick. Good bacteria help us digest food, and a few other things. Let me propose another view. Any bacteria (i.e., bacterial species) will make us sick if it becomes too numerous — so all bacteria are “bad”. All bacteria protect us against other bacteria — so all bacteria are “good”. The terms “good” and “bad” are misleading. It is like saying a person is inherently rich or poor. Anyone, given a lot of money, becomes rich. Anyone whose money is taken away becomes poor. Low bacterial diversity or reduction of diversity makes it more likely that one bacterial species can overwhelm its competitors, producing sickness. When this happens, to say that the species (e.g., H. pylori) that became numerous “caused” the sickness (e.g., ulcers) is to seriously misunderstand what happened and how to prevent it from happening. We are taught that our immune system protects us from infection. We should be taught that bacterial diversity does the same thing. Continue reading “Bacteria are Neither Good nor Bad”
The San Jose Mercury News recently ran a story by Lisa Krieger about a father (Hugh Rienhoff) who found a single-amino-acid mutation that he believes causes his daughter’s growth difficulties.
Born with small, weak muscles, long feet and curled fingers, Beatrice confounded all the experts.
No one else in her family had such a syndrome. In fact, apparently no one else in the world did either.
Rienhoff — a biotech consultant trained in math, medicine and genetics at Harvard, Johns Hopkins and the Fred Hutchinson Cancer Research Center in Seattle — launched a search.
He combed the publicly available medical literature, researching diseases, while jotting down each new clue or theory. Because her ailment is so rare, he knew no big labs or advocacy groups would be interested.
He did some of his own lab work in his San Carlos home, borrowing tools or buying them used online.
A few commercial labs, like the San Diego-based biotech Illumina, offered him help for free. And a wide array of pediatricians, geneticists and neurologists volunteered their opinions.
Over time, he zeroed in on a stretch of genes that control a growth hormone responsible for muscle cell size and number. And he knew he could further target his search — saving time and money by not sequencing Bea’s entire genome, but only the exomes, which are the genes that code for proteins.
This is not a simple upbeat story. The father is a genetic researcher and doctor. I agree, he has made considerable progress in understanding the cause of his daughter’s problem. Not addressed are two questions: 1. Why is he sure he has the right mutation? Perhaps his daughter has other mutations. I’m sure the father understands this, the journalist may not. 2. What about environmental causes? As Aaron Blaisdell’s story shows — Aaron has/had a single-gene genetic disease that vanished when he changed his diet — single-gene diseases may respond to environmental changes. Early work with bacteria emphasized this. If Rienhoff had spent equal effort in trying to find environmental changes that help, he might be further along in discovering them. An obvious place to start would be testing different diets. There is no sign he has done that. His knowledge of genetics, plus the brainwashing that doctors undergo (they are told genes are incredibly important), may have led him to waste a lot of time. Someone with less understanding of genetics may realize better than Rienhoff that knowing what genes have changed may be very little help in finding helpful environmental changes.
Thanks to Allan Jackson.
Persons with Type 2 diabetes have an increased risk of heart disease and stroke. They are usually overweight. A study of about 5000 persons with Type 2 diabetes who were overweight or worse asked if eating less and exercise — causing weight loss — would reduce the risk. of heart disease and stroke. The difficult treatment caused a small amount of weight loss (5%), which was enough to reduce risk factors. The study ended earlier than planned because eating less and exercise didn’t help: “11 years after the study began, researchers concluded it was futile to continue — the two groups had nearly identical rates of heart attacks, strokes and cardiovascular deaths.” Continue reading “Big Diet and Exercise Study Fails to Find Benefit”
Anne Weiss recently repointed me to an interview with the epidemiologist Tom Jefferson about swine flu. Jefferson, let me stress, is a good epidemiologist. In the interview he makes a point I make on this blog, that research is heavily shaped by two questions: 1. what will make money? 2. what will be good for my career? (How curious that economists — with the exception of Veblen and Robin Hanson — spend so much more time on #1 than #2.) For example: Continue reading “The Fallibility of Epidemiologists: Neglect of the Immune System”
A week ago I had my teeth cleaned. So dirty! said the dental hygienist. This wasn’t surprising. Because I am in China a lot, I get my teeth cleaned only twice per year. Long ago they got dirty so fast my dentist insisted on four cleanings per year. “But aren’t my gums okay?” I asked the hygienist. They felt okay. Not tender. They did’t bleed when I flossed (which wasn’t often). No, she said. You have pockets of 5 (= 5 mm depth). There is bleeding. Indeed, when I washed out my mouth with water at the end, there was some blood.
Yesterday I had my teeth examined. The hygienist was wrong. Almost all my pockets were 2’s, with a few 3s. That’s very good and a vast improvement from the 4s and 5s I had before I became a big fan of flaxseed oil. My gums improved exactly when I started drinking flaxseed oil, no doubt because the omega-3 in flaxseed oil reduces inflammation. My gums were fine in spite of all the plaque — which is supposed to make gums bad. Apparently the hygienist was so devoted to her theory (lots of plaque = bad gums) that she failed to see an exception she stared at for 30 minutes.
There is a well-established correlation between gum disease and heart disease (more gum disease, more heart disease), probably because both are caused by inflammation. So good gums is very good news — it shows I am doing a good job of reducing inflammation throughout my body. These results also support two of my pet theories:
1. Studying what foods make the brain work best is a good way to improve overall health. I started studying flaxseed oil, and how much to take, because I discovered by accident that it improved my balance. Experiments (what is the effect of flaxseed oil on my balance?) soon showed the optimum amount/day was more than flaxseed oil makers recommended! Before I started eating lots of butter, the optimum for me was about 3 tablespoons/day. After I started eating lots of butter, the optimum seems to have gone down to 2 tablespoons/day. Gum improvement seems to be easy to notice at about 1 tablespoon/day.
2. Our health care system fails to get the simplest things right. Omega-3 is not a mysterious nutrient. It has been shown to improve health in thousands of studies. It is well-known that it is anti-inflammatory. It is also well-known that too much inflammation is a major problem. Even so, our health care system has failed to grasp that a large fraction of the population eats too little omega-3 and this has an easy fix. Other examples of failure to get the simplest things right include gastroenterologists not realizing that digestive problems may be caused by food, dermatologists not realizing that acne may be caused by food, and everyone not realizing that cutting off part of the immune system (tonsillectomies) is a terrible idea.
What other simple things does our health care system get wrong?
Scurvy is a disease of civilization because you need civilization to make long ocean voyages. It is the first disease of civilization to be understood and eliminated. In a paper called “Innovation and Evaluation” (gated), Frederick Mosteller, a professor of statistics at Harvard, noted how long it took. In 1601, James Lancaster, a sea captain, did an experiment involving four ships on a long voyage. Men on one ship got lemon juice, men on the other three ships did not. The men given lemon juice were far less likely to get scurvy. In 1747, James Lind, a doctor, compared six purported cures for scurvy. Lemons and oranges (one cure) were much better than the other five (as Lind expected). In 1795 the British Navy started using citrus juice regularly and wiped out scurvy on their ships. In 1865, the British Board of Trade recommended citrus juice for commercial ships. It took more than 200 years for a simple and effective remedy — discovered before Lancaster — to spread widely.
The sailors at risk of scurvy did not control what they ate. The people who controlled what they ate never got scurvy. Sure, the people who controlled what sailors ate did not want them to get scurvy (high rates of scurvy were a big problem) but they also had other concerns. The lesson I draw from this story is do not let anyone else (doctor, expert, etc.) solve your health problems for you. Sure, other people, as part of their job, will sell you something, provide advice, write a prescription, provide therapy, do surgery, whatever. It might work. They want to help you — the more they help you, the better they look, the more business they attract. But it is entirely possible, this bit of history teaches, that they are slow on the uptake or have conflicts of interest and a much better solution is available.
Thanks to Steve Hansen.
First do no harm . . . As Robin Hanson has said, what does that mean? In contrast, the rule illustrated by this story, from Bryan Castañeda, who works for a Los Angeles law firm, is quite clear:
At the old firm I used to work at, I was talking to one of the senior attorneys and the topic of medical malpractice cases came up. He said he avoids them. Why, I asked. He said — I’m paraphrasing here — “Because you won’t find a doctor who will testify against another doctor in open court. They may advise you in private, ‘Oh yeah, so-and-so definitely screwed up,’ but you won’t get them to say that on the stand. They all protect each other.”
Judging by this story, if your doctor makes a mistake, the only person who will suffer consequences is you. Thank heavens the rest of us have more power than ever before. A recent survey of doctors found that “more than a 10th (11.3%) admitted to telling patients something that was not true.” The survey did not ask about lies of omission (when silence is misleading); unwillingness to testify that someone else made a mistake is that sort of lie. The survey also showed that doctors (at least, those who took the survey) have a self-serving interpretation of the term not true. Although only about 10% said they had said something “that was not true” — meaning something that they knew wasn’t true — “more than half had described a patient’s prognosis more optimistically than warranted.” Apparently they consider such descriptions not instances of “not true”.
In Systems of Survival, Jane Jacobs described two moral systems (lists of rules/values): The guardian syndrome and the commercial syndrome. In certain areas of life (e.g., military), the guardian syndrome prevailed; in other areas (e.g., small business), the commercial syndrome prevailed. Loyalty (e.g., “never testify against a fellow doctor”) is a guardian value — indeed, the main guardian value. In contrast, honesty is the main commercial value. Jacobs said that the two syndromes corresponded to two ways of making a living: taking and trading. Doctors do not represent themselves as predatory (= taking). But, according to Jacobs, this sort of rule (“never testify against a fellow doctor”) puts them squarely in that camp.
I asked Jim Jacobs, one of Jane Jacobs’s sons, for comment. He replied:
Exactly right. Jane experienced this herself, unfortunately. It’s really a major problem. I see the very same behavior among medical researchers too.
Because I am in China, I want my new credit card sent here. After 45 minutes arranging this, my credit-card company asked me one last security question: What were the last four digits of the bank account used to pay my most recent bill? I told them. They said my answer was wrong. Huh?
I pay my credit card bills through Fidelity Investments (which is not a bank). I contacted them. I was routed to their BillPay department. The person who helped me, whose name I wish I had written down, said that he was as puzzled as I was. It was not clear at all why my answer was wrong. He suggested a conference call. He started a conference call with my credit-card company. Within a few minutes, he and the credit-card company representative figured out that there was a mistake in the number listed by the credit-card company. Their software had lost the last digit of my account number, so that if my account number had ended in 12345, their records would have showed 1234. (Yet the payment still went through.)
I was greatly relieved. “At least the problem had a solution!” I told the credit-card-company representative. Imagine not being able to control one’s money because of a software error. I was/am grateful to the Fidelity representative for quickly solving a problem that had nothing to do with Fidelity.
You might think that such heavily-used software would by now be free of bugs. But it wasn’t.