Friday, September 28, 2007

Why should we eat all those fruits and veggies?

grilled veggies
Their benefits against gut cancer are minimal, as shown in a new overview of fourteen studies, but this is most likely not the point. Just because any healthist, hoping to prolong his life by eating healthy food, must be very disappointed by the facts that I am going to present here. But we should not care too much due to the fact that really delicious food, slow food, grande cuisine, is unconceivable without fruits and veggies.

The facts

Fourteen studies about fruit and vegetable intake and the risk of colon cancer with a total of more than seven hundred thousand men and women have been pooled for a new analysis; more than five thousand of these persons have been diagnosed with colon cancer. Conclusion of the authors:

"Fruit and vegetable intakes were not strongly associated with colon cancer risk overall but may be associated with a lower risk of distal colon cancer."
It is very interesting to see what “not strongly" means: In a hundred thousand who eat less than 200 grams (7 oz) fruit and veggies a day, 61 will get a colon cancer within a year, on statistical average. In a hundred thousand who eat at least 800 grams (28 oz) daily of fruit and veggies, this figure is somewhat lower but still 54 cases a year. Thus, for preventing one case of colon cancer, fourteen thousand years of switching from a low to a high fruit and vegetable intake is required. This is not what we call a reasonable effect. Only with the magnifying glass of a detailed analysis, the researchers have found that cancers in the most downward region of the gut, but not in other regions, may be prevented to a certain extent by a high fruit and vegetable intake.

What really matters

I think that this study should give us some sense of relief: All those telling you that you should stop to eat this and better eat that, have lost another piece of reason for their claims. Fruit and veggies are yummy, this is what matters. And a steak is also okay, see my earlier post about saturated fats. So we should welcome every null study about food, telling us that we should not eat by health prescriptions but learn to better enjoy high quality food and to let our natural feelings take control.

Photo credit: flickr.com/photos/caribb/274516861/

Thursday, September 27, 2007

Body mass helps elderly asthmatics to survive

elderly
Elderly asthmatic patients with a body mass index above 25 survive better than the so-called normal-weights, and those with a body mass index below 22 have the highest risk. This finding of an Italian study on asthma in the elderly is one more example of the so-called obesity paradox: In contrast to the widely held belief about body fat, it shows a positive link to health in this special condition. Other known conditions are heart diseases and, in general, old age.

About two hundred asthmatics of at least age sixty-five and more than a thousand elderly suffering from other chronic diseases have been followed five years on average. Mortality was fifty percent higher with asthma than with other chronic diseases. In asthma, but not in other diseases, the mortality is linked to body mass index in an inverse fashion, that is, lowest mortality with highest body masses and vice versa.

This study tells us nothing about possible causes. But it is one more case of refuting the still widely held negative belief about body fat and health.

Photo credit: flickr.com/photos/foreversouls/205896064/

Health Blog Carnival Watch 1:11

Grand Rounds Anniversary Edition
Kevin MD opens the fourth year of Grand Rounds with another excellent bunch of posts, from abbreviations to keeping nurses happy, from bad to good ideas, heartbreaking and mind-boggling stories, on gadgets, studies, dos and don'ts in medicine and healthcare, and many more. Enjoy!
September 25, 2007 at Kevin MD

Grand Rounds 3:52
This nice edition by Kerri comes along in a food shopping style and she has gathered many interesting items in her basket.
September 18, 2007 at Six Until Me

Oekologie #9
This carnival is about environment but also features some health-related posts.
September 15, 2007 at Fish Feet

The Skeptics Circle Saloon
In this edition, Brent Rasmussen shows his talent as a western novel writer, and it seems that not very much has changed since the times of snake oil peddlers. Fortunately, we have Doc Orac and many others who can tell us the real truth and debunk the lies. But this can be a tricky job. What you always wanted to know about quackery, myths, and refuting of false claims, you read it here.
September 13, 2007 at Unscrewing The Inscrutable

Grand Rounds 3:51
The theme of this edition is healthcare innovation and new technologies. There are a wide variety of posts, including many that discuss innovations and many that discuss the implications of new scientific knowledge and technologies.
September 11, 2007 at The Efficient MD

Wednesday, September 26, 2007

New Swiss food pyramid allows more fat

Swiss food pyramid
The new guidelines lower the recommended carb amount from 60 to 45 percent, raise protein from 10 to 15 percent and raise fat from 30 to 40 percent, according to Paolo C. Colombani, head of the Swiss food pyramid expert group. Colombani puts the value of some public recommendations about nutrition into question, saying that there is no sufficient evidence to prove that saturated fats are bad for health. The new Swiss food pyramid has been in use for two years and its impact on the amounts of food components has been analyzed recently at the ETH Zurich.

In an article in the Neue Z├╝rcher Zeitung of today Colombani points out that mother's milk contains high amounts of saturated fats, and there is no better food for a baby than mother's milk. Fats have been said to be harmful for the heart, but the heart takes 60 to 90 percent of its energy out of fat. And the vast majority of published studies in the past fifty years have shown no adverse effects of saturated fats.

Given the fact that food pyramids are changed every couple of years, that they look different in every country, sometimes stratified horizontally (the original idea of the pyramid) and sometimes vertically as in the new American food pyramid, we have to ask ourselves if they are useful at all.

Food pyramids may even do harm in promoting restricted eating, that is, eating by prescription rather than by one's own feeling of hunger and satiety.

Photo credit: Swiss Society for Nutrition

Tuesday, September 25, 2007

Tea may be an upper, but not for blood pressure

coffee and tea
Both coffee and tea may make you alert but if blood pressure is a problem, you may fare better with tea. The reason has been demonstrated in a trial about the effect of isolated substances from tea and coffee on mood and blood pressure. Caffeine is found in both tea and coffee, it raises alertness as well as blood pressure. Theanine, found in tea only, has the same effect on mood but lowers the blood pressure. Thus, in tea, two compounds are acting in different ways on blood pressure which, as a result, remains more or less stable.

With coffee, on the other hand, blood pressure may rise for a short time, but not in the long run. There is no reason for coffee drinkers to be anxious about blood pressure or heart risk. But for those who must take prescribed pills against high blood pressure, tea may be a better choice.

Photo credit: flickr.com/photos/markie555/251230621/

Monday, September 24, 2007

More statin may save lives after heart attack but so may red wine

red wine
A higher dose of lipid-lowering statin may save one in ninety-five lives after a heart attack, but the added benefit is in the same range as a daily glass of red wine.

Two studies about the benefit of a high (80 mg) compared to a standard or moderate (20-40 mg) daily dose of statin after a myocardial infarction have been pooled to assess the impact of statin dose on mortality. A total of eight thousand patients have been analyzed. It came out that ninety-five patients must be treated with aggressive instead of normal statin therapy for two years in order to prevent one death; the mortality rate dropped from 4.9 to 3.6 percent.

Same range of benefit ...

A similar drop in mortality has been found comparing abstainers with consumers of alcohol: With moderate alcohol consumption, mortality from all causes dropped from 6.3 to 3.4 percent. The types of drinks have not been separated in this study but there are reasons to assume that red wine is particularly beneficial.

In the statin studies, the therapy has been started after the heart attacks. In the alcohol study, the consumption one year prior to the heart attacks has been assessed. Therefore, the two studies are not directly comparable. But it is still interesting that they come to a nearly identical range of benefit.

We also must take into account that statin studies are funded by statin manufacturers, therefore we always should be suspicious about a possible bias towards a better outcome. The cited alcohol study has been funded partly by the National Institute on Alcohol Abuse and Alcoholism, thus any conflict of interest may be excluded.

... and same range of cost

The additional costs of intensive versus standard statin therapy have been estimated about 1.40 dollars per day. For this money you get a glass of good wine and much more pleasure than from swallowing a pill. Warning: I you have been prescribed a statin, never change taking it without consulting your physician.

Photo credit: flickr.com/photos/drh/863206054/

Friday, September 21, 2007

Low blood sugar is the motor of the yo-yo

yo-yo
Try to lose weight and you may end up heavier than before; it seems that you must avoid low blood sugar levels in order to prevent the yo-yo. This is the conclusion of two Canadian studies about blood sugar levels and weight gain. In the first study, blood sugar levels have been measured in more than two hundred fifty adults, and six years later, those with the lowest levels have gained most weight. In the second study, more than forty persons classified as "obese" have participated in a weight loss program, and the more weight they lost, the lower blood sugar levels have been measured and the more weight they regained in the long run.

The blood sugar levels have been measured not in the fasting state but two hours after a so-called glucose tolerance test with a standardized sugar solution that makes the blood sugar level first rise and then fall again. This test re-enacts what happens if the body, after a fasting period, only gets a small amount of food: The blood sugar may even fall below the fasting level after the test, signalling the craving for food to the brain.

Ho to prevent the yo-yo

If the attempt to lose weight lowers the blood sugar level and if low blood sugar levels predict weight gain, then deliberate weight loss in the long run is a mission impossible. This is exactly what has been observed in close to a hundred percent of all those who have tried and have failed. In the light of the Canadian studies this is no surprise. The blood sugar mechanism leaves just one solution: Never try to lose weight by staying hungry or you will regain more than you have lost.

Photo credit: flickr.com/photos/minow/504976780/

Thursday, September 20, 2007

Bad ranks for hospital ranking sites

hospital compare
The best accessible websites offer more transparent but less appropriate data, all in all the results are often outdated and inconsistent. That is, you do not get easily what really matters, and one hospital ranked top on one site may be at the bottom on another site. Plus the data displayed on the sites may be up to two years old. This is the sobering conclusion of a survey in six hospital comparison websites done by Michael J. Leonardi and co-workers of the University of California, Los Angeles.

One government (Hospital Compare), two nonprofit (Quality Check and Leapfrog Group), and three not specified proprietary sites have been tested. Really interesting data such as surgical outcome measures are only provided by the proprietary sites, and these do not rank top in search engines, two of them take a fee for showing the data. None of the sites explicitly define terms such as complications.

A way out of the data jungle?

Thus, as a consumer of hospital services, you may get easy information that is worth close to nothing, or you may get information that could be valuable, but most likely is inaccurate, outdated or biased, and you may have to pay for it.

Even worse, assuming that these problems will be overcome in the future and you'll get reliable mortality data from surgeons: High mortality rates just may reflect the fact that the best surgeons take care of the most difficult cases.

But there may be a simple solution: For any planned surgery, try to find the hospital with the highest case numbers because it will increase the odds of survival. This has been shown time and again, for instance in stroke, in oesophagus cancer surgery, and in pediatric heart surgery - just to pick some of the most recent studies.

Wednesday, September 19, 2007

Baby's birth weight shows mother's health

baby in NICU
A birth weight in a broad normal range signals low heart attack risk in mothers, but extremely low or high birth weights may double the risk. Even the health of fathers, to a much lesser extent, seems to be related to the birth weight of their offspring. This is the result of an Israeli study in more than thirty thousand mothers and fathers, respectively, where birth weights of offspring and mortality of parents have been assessed.

Good news for mothers of babies born in the normal range of 2500 grams (5 lb 8 oz) to 4000 grams (8 lb 13 oz): Their risk of death from heart attack is lowest. Compared to these mothers, the heart risk is approximately double in mothers who give birth to smaller or bigger babies. In contrast to the U-shaped curve in mothers, it is linear and much less pronounced in fathers: With growing size of their offspring, their risk of death from any cause slightly decreases by about five percent of the total risk in best case. Other than in mothers, birth weight is not particularly linked to the heart attack risk in fathers.

Genes and long-term consequences

To what extent genes and environment play a role here is not yet clear. The association to fathers' health clearly points to genes. In addition, birth weight is inherited to a certain extent: Women who have been born with low weight have a tendency to give birth to low weight babies as has been shown in a Swedish study. A vast number of studies have linked low birth weight to bad health later in life, up to the old age.

It is good to know the risk

While parents cannot change their genes, they can make sure not to smoke and to avoid secondhand smoke in pregnancy. Once a baby is born low-weight, a healthy lifestyle is important not only for the baby but also for the parents, in particular for the mother. There are so many risk lowering factors that can be changed - being physically active, eating fruit and vegetables, enjoying life and coping with stress - that a known risk can be more than compensated.

Photo credit: flickr.com/photos/iamthechad/15398250/

Tuesday, September 18, 2007

What has breast cancer survival to do with body fat?

women walking
Weight gain seems to be a risk at first sight, but it disappears when physical activity, nutrition and race are considered.

Obesity has been linked to a poorer survival in breast cancer patients, and one more of those studies have been published recently, suggesting that weight gain prior to breast cancer diagnosis can decrease survival. Compared to women who maintained their weight in a range of plus or minus three kilograms (six pounds), those who gained more than sixteen kilograms (35 pounds) from age twenty until one year before diagnosis had a double risk of mortality from breast cancer or from any cause.

Physical activity and nutrition more important than weight

At this point it is important to note that such a link or correlation does not imply a cause. In particular, no weight advice can be derived from this study. In order to learn more about the possible causes, we must have a closer look at other findings.

For instance, in a Californian study, physically active breast cancer patients with a high fruit and vegetable intake survived better, regardless of their weight. Many women of higher weight are less active and eat less fruit and vegetables, therefore weight seems to be linked to poor survival. But among the women with a healthy lifestyle, weight has no influence on survival. Being physically active and eating fruit and vegetables has found to reduce the risk by 50 percent with any weight.

The role of genes

We conclude: A healthy lifestyle may prevent weight gain in some women but not in others, and for these, their weight will not be a health problem.

Many more influences, such as genes, also play an important role in breast cancer risk and in body weight. A study in more than fifty thousand women has shown that body size has no negative influence on breast cancer risk in black women. On the contrary, a higher body mass (so-called "overweight") even lowers the risk of breast cancer in black women. White women, of course, cannot hope to profit from a similar genetic advantage.

Photo credit: flickr.com/photos/congvo/1395431872/

Monday, September 17, 2007

What has diabetes to do with body fat?

sugar cookie
Genes seem to play an important role, challenging the value of weight loss to prevent diabetes. One of these genes, the adiponectin gene SNP276, has been linked to diabetes and obesity in a Taiwanese study with more than a thousand elderly persons. This gene determines different variants of the hormone adiponectin, produced by body fat cells. Adiponectin lowers the risk of diabetes and heart attacks. But some adiponectin variants are better than others. The variant (allele) G is considerably better than variant T. The highest risk of diabetes and of obesity has been found in persons with the combination TT, that is, having got the bad variant of the gene from both mother and father.

The bad variant seems to be a common cause of a higher diabetes risk as well as a tendency to accumulate more body fat. Both outcomes can be linked to the gene, but of course other factors like the amount of consumed food and the physical activity must also be taken into account. The study authors conclude:

"Genetic variation of the adiponectin gene is associated with obesity (...) and diabetes mellitus in the elderly. The genetic effect on diabetes mellitus is partially independent of BMI."
When diabetes is partially independent of body mass index, weight loss will be partially useless in the fight against diabetes.

And what about the other part?

But genes cannot explain the whole story. There is still one part of diabetes that may be linked to body mass index, regardless of the genes. But this study does not allow any conclusion about causes, because neither food nor physical activity have been taken into account. Thus, not even the non-genetic rest of a link between body fat and diabetes is in favour of weight loss.

Photo credit: flickr.com/photos/princess_of_llyr/223358802/

Sunday, September 16, 2007

Strange advice by a war on obesity site

weight concern
Hard to believe but you may be told that your weight is okay, you gain two pounds, and then you are told you should lose sixteen pounds! Or even better: You may be told to be "not overweight" at age 13 but "overweight" at age 12 with the same height and weight.

Surprised? Then you should try out the Body Mass Index calculator at Weight Concern, a leading war on obesity site in the UK. I have tested this calculator with my own height (182 centimetres) and various weights (in kilograms, which is roughly the half value in pounds). For instance, I got this result:

82 kilograms
"Your weight is in the healthy range for someone of your height."
Then, after having some good meals virtually, I gained a little weight, once again tested myself and got this advice:
83 kilograms
"Your BMI puts you in the overweight category. You would improve your health and feel better if you lost 8 kgs. Even a loss of 4 kgs would improve your health."
I have gained one kilogram and should now lose eight kilograms or sixteen pounds? This is really hard to grasp. After having checked the content of the site I have been confirmed that a weight of 82 kilograms is healthy for my height. The way I learned it at school, this makes one kilogram down from 83.

Another thing that leaves me suspicious: They don't ask me, as an adult, about my age and my sex. Is one weight good for all? Hard to believe, and when it comes to old age, a number of studies tell us that a higher body weight is linked to a longer life. And your health status? A higher body weight may be indicating a longer life of heart patients.

What happens between age twelve and thirteen?

For kids and youngsters they have a separate BMI calculator. Well, I cannot shrink myself but I entered my real height and weight values and stepped down my age. Of course, a twelve year old will not be as tall as me, but this should not matter because body mass index accounts for height and just gives a proportion. In other words, as long as the BMI stays within a reasonable bandwidth, the advice should not be affected by my unusual height and weight. After having rejuvenated myself by 46 years I got this advice (emphasis is mine):
"A 13 year old child/young person whose weight is 72 kg and height is 182 cm is not overweight. If you have any concerns that they may be underweight, you should see your doctor."
Not overweight? Underweight? Is there nothing in between? I rejuvenate myself by another year and get this advice:
"A 12 year old child/young person whose weight is 72 kg and height is 182 cm is overweight. It is important that he or she does not become more overweight or obese - you may wish to visit the children and families page, for further information."
I didn't change my weight and my height, but at age 13 I am not overweight, possibly even underweight, and at age 12 I am overweight? If this is not nonsense, what is it?

And what about body fat and hormones?

In every war, propaganda tries to tell evil stories about the enemy. In the war on obesity, body fat is the enemy. Here is what they tell about it:
"Excess body fat is not harmless tissue that you carry around with you as extra padding. Excess body fat produces hormones that can make you susceptible to a number of serious illnesses - the more you are overweight, the greater the risk."
Now let's turn to the facts. Adiponectin, one of the hormones produced by body fat, reduces the risk of diabetes and heart disease and is produced to a lesser extent as body fat grows - a double contrary to the claim. The other hormone, leptin, regulates appetite and metabolism which is not bad in itself. The only problem with this hormone is that the body may lose its sensitivity to leptin, and as a reaction the body begins to accumulate fat which in turn produces more leptin. This excess leptin may increase the risk of some diseases but the source of the problem is probably not body fat but the blunted reaction of the body to leptin. The claim that body fat in itself is a cause of diseases (rather than a concomitant feature) has not been proven in scientific studies.

Conclusion

The Weight Concern website advises people, once classified as "overweight" by rigid official standards, to over-react and lose far more weight as has been stated as healthy by the same standards. There is no study showing that such a weight loss will improve health, and the fact that most people losing weight regain it in the long run shows that the claim of "feeling better" with lower weight is not justified. The BMI formula for young people and children seems to be doubtful to put it mildly, causing an intriguing leap of advice between ages 12 and 13. In order to build up body fat as an enemy, the role of hormones is described in a simplified, contorted and biased way. All in all, you may leave this site more confused than before your visit.

Saturday, September 15, 2007

The tricky job of quackbusting

quackery ad
Just tell the truth and refute false myths without repeating them because our long-term memory is good at storing details but bad at keeping track of true and false. This weakness of human memory makes mythbusting look like a mission impossible, but just try the best you can. After all, it is a must to save people from losing money on dubious treatments or even be harmed by them.

Thanks to Skeptics Circle I came to know about a study presented by Mark Hoofnagle and with very detailed comments by Sandy Szwarc: Volunteers have been shown a flyer of the Centers for Disease Control (CDC) that has been edited in the conventional and serious way: presenting false myths about health, debunking them using scientific facts, and presenting the correct information. Only half an hour later, older people misremembered 28 percent of the myths as true, and three days later the fault rate went up to 40 percent. Younger people made the same faults but to a lesser extent. So we may assume that this is a specific weakness of human memory which is known to lose some of its power in old age. Best we can remember are the details, and much less we can remember if they are true or false. Even more: The more often we hear a myth or a lie, the more probably we are inclined to believe it. Every propaganda makes use of this fact.

A piece of mythbusting drill

I have been told that Med Journal Watch is doing a good job, but of course I am not yet satisfied. When I look at this old post I am not quite sure if I didn't contribute to myths about vitamins and arthritis. Today, I no longer would mention arthritis in the title but, for instance, something like "multivitamin claim refuted".

Anyway, this medical myth study has motivated me to do a little public training in order to improve my debunking fitness and as a finger exercise for the quackbusters among my readers. Look at the historical quack ad at the top of this post; our task is to write a retrospective blog post title and first sentence, assuming that the "great new invention" has been refuted by a controlled study. Let's have a try: Violet ray vibration useless (and not Violet ray vibration does not stop pain). A new device that is being sold to patients does not show the effect that has been claimed by the merchant (again avoiding to mention pain or other details). This is the outcome of a controlled study ... - only here I should bring up the details, for instance that the study has been done with patients suffering from pain and that there has been no difference compared to placebo. Then we conclude that the merchant makes false claims, that the device is useless, and that consumers should not lose their money on this hoax. Finally we give some good advice against pain.

Photo credit: flickr.com/photos/eklektikos/99904243/

Friday, September 14, 2007

Keep moving when told to have weak bones

old woman moving
Knowing her bone status is a good thing for an elderly woman, but this awareness may have a serious side effect. Instead of lowering the risk of bone fractures, it may increase it, as a Danish study shows: Knowing to suffer from osteoporosis makes women anxious, thus being less active. This makes the bone mineral density decline even faster, increasing the risk of falls and bone fractures.

In-depth interviews revealed that the women who have been told to have osteoporosis strongly underrated what their bones could endure. They wrongly imagined them as fragile and believed they must avoid every strain. But just the opposite is true: Only physical activities can stimulate the formation of bone mass and prevent a too rapid bone loss in older age.

Dare it and bear it

According to the Danish study, all persons suffering from osteoporosis should be encouraged to engage more than before in physical activity, especially of the weight-bearing kind. This is likely to reduce the risk of bone fractures inside and outside of the body: Inside because the bone loss is slowed down, and outside because of a better motion skill in actual situations where a fall could happen.

Photo credit: flickr.com/photos/9282628@N07/1298957040/

Thursday, September 13, 2007

Weight concerns may be bad for your health

weight check
Not the real weight but feeling overweight is linked to being a couch potato. This has been shown in a study where real weights and weight perceptions of adults have been linked to physical activity and nutrition: More than sixteen thousand Australians have been surveyed. They have been asked about their height and weight, whether they rated themselves as "acceptable" or "overweight", how often and how intensely they engaged in physical activity, and what food they consumed.

It came out that those rating themselves as "overweight" were less active than those who see their own weight as "acceptable" - no matter of their real weight. In other words, persons may be rated as "overweight" or "obese" according to international standards, but as long as they do not care and are happy with their own weight, they maintain the same level of healthy physical activity as the so-called normal-weights.

Besides, meeting the recommended intake of two fruit and five vegetable servings a day does not show any relation to the real or to the self-rated weights in this Australian study.

The drawback of weight concerns

The study authors conclude:

"Overweight perception may be another barrier to physical activity participation among men and women with excess body weight. Public health strategies might need to focus on overcoming weight perception as well as weight status barriers to adopting healthy physical activity behaviors."
This sounds like asking for the impossible as long as public health campaigns in the world-wide war on obesity try to raise the weight awareness in more and more people. Ironically, the study authors themselves contribute to what they have found to be a problem, using the label “acceptable" for the normal category of real weights.

Photo credit: flickr.com/photos/digioreo/109774293/

Wednesday, September 12, 2007

Shape matters for heart risk, weight doesn't

woman
When it comes to the risk of a heart attack, only the waist to hip ratio is important but not the body mass index, according to the Dallas Heart Study. More than two thousand Texans have been examined, using various measures of obesity and computer tomography for assessing the calcification of coronary arteries. The more calcium is found in the coronaries, the more serious is the heart disease and the higher the risk of a heart attack.

Main results: The most widely used obesity scale, body mass index (BMI), is only marginally linked to coronary calcium, and this link disappears when other risk factors are taken into account. The same is true for waist circumference. Only the waist to hip ratio (WHR) shows a relation to coronary calcium, with a double risk for those with the highest WHR values, compared to those with the lowest values.

Not the fat matters but where it deposits

The woman in our picture has a waist to hip ratio of about 70 percent which is an ideal value for a woman - similar to Marilyn Monroe, Sophia Loren and the Venus of Milo. For a man, the best value is about 90 percent. Waist to hip ratio is measured as follows: Take a non stretchable tape, measure the waist at its narrowest point, usually above the belly button, and the hips at the widest point of the hip bones. Then divide the waist circumference by the hip circumference.

Just a link but not a cause

A fat belly, but not fat in other places of the body, is linked to the risk of a heart attack. This is just a link, not more. It does not mean that fat at the belly (but not at other places) is doing harm to the arteries. In fact, a study has found that belly liposuction surgery does not improve heart risk factors. Thus, it is more reasonable to assume that certain causes such as genetic disposition, nutrition and lack of exercise may lead to belly fat on the one hand and to heart disease on the other hand.

Photo credit: flickr.com/photos/7258769@N02/1024217616/

Tuesday, September 11, 2007

Be smart, use your cerebellum

playing the violin
Besides fine-tuning of movements it also helps thinking; it seems that we still underestimate this small but ingenious part of the brain.

Despite of being much smaller than the brain hemispheres, the cerebellum contains about half of all brain cells. Their main function is the coordination of movements in time and space, but new research has revealed its important role in attention, learning, memory and language. A number of diseases that lead to cognitive deficits, such as Down's, Williams or fragile X syndromes, dyslexia or ADHD also affect the cerebellum. In prenatal alcohol exposure and in extreme premature births, the cerebellum or parts of it grows unusually small. A disease that destroys parts of the cerebellum, ataxia teleangiectasia, reduces the verbal IQ and affects the ability of estimating a duration. These are just hints that the cerebellum may be more important for our intelligence than has been thought, but research is still in its beginning.

How to use the cerebellum

When deficits affect the intelligence, training of the cerebellum may boost it. Playing a music instrument is a typical cerebellum job; professional keybord players have a larger cerebellum than non-musicians. Singing, dancing, biking, golfing, juggling, climbing, playing ball games and many more activities that require motor skills are also fine.

The result may be rewarding, in addition to being fun. A number of studies have shown that playing a music instrument can make you smarter. Just one example: In a Canadian study, the IQ of schoolchildren has been increased after music lessons.

Photo credit: flickr.com/photos/jeanettewarner/394151645/

Monday, September 10, 2007

Should walkers better jog?

family walk
The current physical activity guidelines are too lax, according to British sports physicians. But they may have forgotten the pleasure factor and the influence of the individual fitness level.

Health guidelines in Britain recommend physical activity of moderate intensity, and this message has reached its target. But the public got it wrong, as two physicians of the School of Sport and Health Sciences at the University of Exeter want to convince us. In a survey of more than a thousand adults, 56 percent of men and 71 percent of women stated that moderate activity is better for health than vigorous activity. This "erroneous belief" should be corrected by amending the current guidelines.

How much is too much?

Do we really need tough public health drill sergeants who push us to hard workouts? After all, leisure time physical activity is supposed to give us pleasure and relieve our stress.

It may be true that vigorous activity could be better for health, but the most important factor is time spent in either moderate or vigorous activity. Time, on the other hand, is depending much on motivation, hence on pleasure.

The importance of fitness

The individual fitness level is also very important when it comes to general recommendations. What is "moderate" and what is "vigorous"? The self-perceived exertion level is inversely related to fitness, according to a Danish survey in more than two thousand adults of all ages. That is, a fit person will rate an activity as moderate and an unfit person will rate the same activity as vigorous. Not very surprising, but it has to be taken into account for public recommendations.

Photo credit: flickr.com/photos/pinkangelbabe/1252219802/

Friday, September 7, 2007

Sons do not shorten maternal life


New research has refuted what Science magazine reported five years ago and what has been cited time and again, and not always properly. Good news for all mothers: There is not the least evidence that giving birth to a son as compared to a daughter ever has shortened or ever will shorten the life of a woman.

Back in May 2002, Helle and co-workers have analyzed population register data of pre-industrial Sweden and found that giving birth to sons shortened the life of women. They were even ready to explain this correlation: Sons, in their opinion, are a greater physiologic burden than daughters, and the testosterone produced by the male fetuses may have a negative impact on the hormone balance of the women.

Despite the fact that this analysis has been restricted to a pre-industrial population, the finding has been spread by popular media as relevant for women of today: "Those sons really will be the death of you, mom" has shown up at position 20 of a Google search today.

More data unmask a bias

Recently, Cesarini and co-workers have re-analyzed the Swedish data and published their new findings on maternal longevity and the sex of offspring in pre-industrial Sweden. Extending the original database of Helle and others by considerably more data from the same region and time period, they no longer found any evidence of a negative impact of sons. It seems that the smaller database of Helle has been affected by some variable bias that has not been filtered out properly.

Photo credit: flickr.com/photos/maistora/370381796/

Thursday, September 6, 2007

Speed eating - the ultimate diet

speed eating
You may be surprised, but speed eating has much in common with something that is considered quite the opposite: diet. Let me explain this later and turn to facts. Speed eating contests are becoming more and more popular, at least in some regions of the world. Some champions swallow huge amounts of food in a very short time. How do they achieve such a "performance"?

A radiology study of the University of Pennsylvania has revealed the anatomical secret: Speed eating champions are capable of relaxing the muscles of their stomach to such an extent that it expands to a flaccid sac of a huge volume. The poor crippled organ is in danger of being destroyed, with a surgical removal as the last life-saving resort.

Five common traits

Is it a coincidence that diets and speed eating contests are booming these days? If you look at what they have in common, you no longer may be surprised:

  • Submitting to an authority: You accept others (contest organizers, diet experts) to rule or guide your eating behaviour.
  • Imposed rules of what to eat: You eat what you have been told (by contest organizers, by diet experts).
  • Imposed rules of how much to eat: You eat as much (in a speed eating contest) or as little (in a diet) as you have been told by authorities.
  • Eating as a means to an end: You want to win the contest or you want to lose weight or not to gain weight or lower your blood pressure or cholesterol or what ever.
  • Irrelevance of basic feelings: Your eating is no longer guided by basic feelings such as appetite, hunger and satiety but by self-imposed, other-directed rules and goals.


Photo credit: flickr.com/photos/iirraa/312254202/

Wednesday, September 5, 2007

Have a closer look at your partner

couple
Four eyes see more than two. This old wisdom came to my mind when I found this study about diagnosis and survival of married and single persons with melanoma: Skin cancers in married persons are more likely to be detected in an earlier stage and survival odds are better than in widowed persons.

Of course, marital status is not the point here. The point is a close relationship, increasing the odds of a skin cancer to be detected by a vigilant partner. Maybe vigilant is not the apt word: Caressing, loving, tenderness may be better.

After all, a couple is not a health police team. Good love and good sex have their own value, making us enjoy life, giving pleasure, and the better chance of detecting a skin cancer is just a little bonus that we should not miss.

Photo credit: flickr.com/photos/phitar/99758818/

Health Blog Carnival Watch 1:10

Grand Rounds 3:50
With his edition, Dr. Emer is joining the exclusive circle of fourth-time hosts. It begins with two great, deeply moving posts about death and dying in hospitals. And there is a lot more of good stuff, coming in these sections: patient encounters, health staff concerns, interviews and reviews, health news, policies, advice, and products.
September 4, 2007 at Parallel Universes

Pediatric Grand Rounds 2:9
Clark Bartram, founder and maintainer of this carnival, has decided to switch to a monthly schedule: PGR will be published every first Sunday of the month. This edition deals with money issues, a drop in funding and a huge rise in the price of a treatment plus some media bashing and many more hot children's health topics.
September 2, 2007 at Unintelligent Design

Medicine 2.0
David Rothman, a first-time carnival host, is not particularly happy with the suffix 2.0 and has re-named this carnival Medical Web Geekery for this time. And that's what you find there: Reports on the efforts of Google and Microsoft to enter the field of health and medicine, and many more web-related trends.
September 2, 2007 at davidrothman.net

Skeptics Circle 68
It is a great honour to be listed top of this carnival with my post about poorly funded conclusions of a preterm birth study. Swedish blogger Martin Rundkvist presents another fifteen excellent skeptic posts, many of them health related, for instance about AA meetings, sleep patterns, HIV denialism, and quackery here and there.
August 30, 2007 at Aardvarchaeology

Tuesday, September 4, 2007

Fear of fat makes kids sick

barbie doll
Funded by millions from public money, the message has been hammered into the brains of Swiss parents: Every fifth child is "suffering from overweight", and this disease must be prevented. The campaign has been running for quite a while now, but yesterday experts have warned from the opposite: More and more kids, even as young as ten years of age, suffer from anorexia. Erika Toman, president of the Swiss Expert Network on Eating Disorders (ENES) blames the public health campaign as part of the problem: "That kids are concerned so early about eating is also caused by the mass of information about this issue."

Of course public health campaigns are not the only source of information. Young girls play also with their superslim Barbie dolls. They watch TV commercials selling diet products. They see their parents being concerned about their weight. At table, food is an issue of good and bad rather than a source of pleasure. Instead of training their natural hunger and satiety mechanism, kids interfere this process with imposed ideas about "healthy eating".

What is the effect of this campaign?

supersize trikeSuch super-sized trikes, sleds, and classroom chairs for kids are the visuals of a public health campaign, claiming: "Switzerland is growing fatter and fatter. It takes little for a big change." There has been much debate about fat kids being ridiculed by the visuals, a feeling that I share. The leaders of the campaign have defended it, stating that it does not address the fat kids but only those in danger of becoming fat. That is, all the so-called normal-weights.

But this is even worse, in my opinion. Should kids with a so-called normal weight be concerned about their weight? Of course not. If so, they are candidates of an eating disorder and may end up as very young anorectics.

After all, the job of kids is to grow and become big and strong. At least this has been the message when I was a young boy, helping Hedi, a farmer's wife, harvesting the hay in summer holidays. She put a second huge piece of Swiss cheese in front of me and said: Take it, you must grow big and strong. I took as much as I could eat and never got fat. But this is another story, the story of genes that have their own idea about your shape, regardless of what you eat.

Suggested reading: Food is good to eat (Sandy at Junkfood Science)

Photo credits: flickr.com/photos/cherrysoda/115956078/, Health Promotion Switzerland

Monday, September 3, 2007

Aloe vera may harm the liver

aloe vera
Is aloe vera a wonder herb? If a herb could cure the same disease as it causes, you certainly could call it a wonder. But let me tell the story from the start.

It was last week when I found a report on a 73-year-old woman who was admitted to the hospital for acute hepatitis in Iowa. Extensive lab testing did not reveal the cause of her disease. She was asked time and again whether she was taking any home medications, which she denied. It was only later that she admitted to using oral aloe vera capsules for constipation. After having stopped taking aloe vera, her liver values returned to normal levels. A similar case has been reported earlier in Germany.

Amazing results of a Google search

In search of more such cases I launched Google with the keywords aloe vera and hepatitis and got two completely different kinds of results.

The first two hits lead to the Mayo clinic and to a nutrition expert, both reporting the German case and warning from hepatitis. The third hit was irrelevant.

And now the fourth hit - from Internet Health Library, a self-declared "Alternative Medicine, Complementary Therapy and Natural Health Care Resource":

"Aloe Vera has long been acknowledged for it's beneficial effects for wounds and burns (when applied externally) and there is growing evidence that, when taken internally, it has powerful healing properties. In one study in China, 38 patients suffering from chronic hepatitis were given extract of aloe vera (injections of 10-15ml/kg,ir x4) and it was found that the level of inflammation was reduced by 87% and the researchers stated that they believe the aloe could thereby alleviate symptoms by protecting patient's liver cells."
I must say, I am surprised.

Trying to solve the puzzle

In the Iowa and German cases, the patients have taken aloe vera capsules for a long time. In the Chinese study, patients have been injected aloe vera for a short time. Patients? The abstract of the Chinese study is very short, and it mixes injection trials with rats, mice, dogs and human patients:
"The injection(10-15 ml/kg/d, ip x 4), total glycoside (125-225 mg/kg/d, ip x (3-4); 600 mg/kg/d, ig x 3) and crystal III (120 mg/kg/d, ip x 4) of Aloe vera var. chinensis were found to be effective in lowering the elevated sGPT induced by CCl4, thioacetamide and D-aminogalactose in mice or rats. It was also observed that these agents could protect hepatic cells from the CCl4-induced injury. When dogs were given in with Aloe injection of 0.1 ml/kg/d x 180, no toxicity was noted. The total effective sGPT-lowering rate of Aloe injection on 38 patients of chronic hepatitis with positive HBsAg was 86.8%."
This study seems to be of dubious quality, and in addition it is wrongly cited by the Internet Health Library.

Claims of online herbal shops

To sum up our findings: We have two case reports of liver harm caused by aloe vera capsules and a dubious Chinese study about a positive effect on some liver values after aloe vera injections.

The first herbal shop shows up at position 7 of the Google search. It is selling aloe vera capsules for a great number of indications, stating:
"The benefits of aloe vera are manifold. (...) Other situations in which it appears to work when taken internally include congestion, intestinal worms, indigestion, stomach ulcers, colitis, hemorrhoids, liver problems such as cirrhosis and hepatitis, kidney infections, urinary tract infections, prostate problems, and as a general detoxifier."
And here we are at the end of our miraculous journey that led us from hepatitis as a possible harm of aloe vera to hepatitis as a possible benefit of aloe vera. To achieve such a miracle, it seems that you must cherry-pick a dubious Chinese study, cite it the wrong way and apply it to the wrong aloe vera product.

Take home message
Natural herbs are not harmless, and not all claims of online herbal shops can be trusted.

Photo credit: flickr.com/photos/natesmama/300281665/