sanode medical blog

Women on the birth control pill are protected from ovarian cancer, even decades after they stop taking it, scientists said.

British researchers found that women taking the pill for 15 years halved their chances of developing ovarian cancer and that the risk remained low more than 30 years later. The findings were to be published Friday in The Lancet.

“Not only does the pill prevent pregnancy, but in the long term, you actually get less cancer as well,” said Valerie Beral, the study’s lead author and director of the Cancer Research UK Epidemiology Unit at Oxford University. The study was financed by Cancer Research UK, a charity, and Britain’s Medical Research Council.

Ms. Beral and colleagues analyzed data from 45 studies worldwide, covering 23,257 women with ovarian cancer, 31 percent on the pill. They also looked at 87,303 women, 37 percent on the pill, without ovarian cancer.

The study found that in rich countries women taking oral contraceptives for a decade were less likely to develop ovarian cancer. Without the pill, about 12 women in 1,000 are expected to have ovarian cancer before age 75. But the figure fell to 8 women in 1,000 in those on the pill.

The outer ears are the only parts of the human body that continue to grow until death. Head, trunk, arms, legs, hands and feet, all the inner and outer organs stop when fully grown in adult age. Even the nose of Cyrano de Bergerac did not grow forever. Hair and nails do, but these are expendable items that constantly must be replaced.

In contrast, the human outer ear is something very special. In proportion to body size at birth, it is the biggest of all organs, even bigger than the head. And it continues to grow throughout lifetime, mostly in childhood and then slowly decreasing, but never stopping until death.

The greatest ear length is 52 millimeters (2.04 inches) at birth on average; at seventy years of age it is 78 millimeters (3.07 inches) in men and 72 millimeters (2.83 inches) in women. About half of the growth between birth and old age is reached at age twenty. But the inner part of the auricle, the so-called concha, has reached its final size already at birth. Detailed statistics about ear sizes may be used for forensic age estimations.

After menopause, lung function declines but less so in women with a body mass index well above the values that have been recommended in public health campaigns.

The term “overweight” is becoming more and more dubious as ever new studies are being published showing positive sides of body weight and body fat. Just today I have come across another such study, this time on lung function and menopause.

It is a well-known fact that we have to face: As we get older, our lungs get weaker. This is inevitable and can be measured by the so-called FEV-1 test: Try to exhale as much air as fast as possible in one second; when the exhaled air volume is measured, it gives a good estimate of lung function.

This test has been done in more than four thousand women, aged 45 to 56 and not taking hormones, in Norway. In women, lung function is influenced by the hormones. Thus, women after menopause, on average, perform worse in the FEV-1 test than women still menstruating.

And now we come to the point: The decline of lung function is highest in women with a body mass index (BMI) below 23, and it is lowest in women with BMI 23 to 28. In other words, women who have been (de)classed as “overweight” (BMI 28) are, in many cases, better off than so-called “ideal weight” women (BMI 23), when it comes to the lungs. The ideal weight, according to this study, is the official borderline to “overweight” - BMI 25!

Obeying the natural needs of the body as a simple way to a stable and healthy weight has been found in Dutch youngsters: More than thirty thousand girls and boys have been studied, and it came out that those who use to skip breakfast are at risk of gaining most weight. Breakfast skipping turned out to be the most important risk factor, even more than physical inactivity.

Healthy young people have a good appetite in the morning because the body needs a lot of new energy after the long night fasting period. If this natural need is not met, energy regulation may get out of balance because the body gets signals of energy shortness, resulting in more fat storage. One of the reasons of breakfast skipping is hurry and stress which both are not very healthy conditions.

In people who have gained much weight, a number of health problems have been observed, and the “overweight” or “obesity” has been blamed as a risk factor. But the real problems may not be the weight itself but rather the out of balance energy regulation or the stress.

And this Dutch study has shown that healthy living may be much easier and much less focused on fears than you may have thought: Just eat your breakfast and do not care about fats or calorie counting or diets, and you have best chances to maintain your healthy weight.

When millions of patients all over the world are using remedies without any molecule of active substance, there must be at least one natural mechanism that rewards nonsense. And such a mechanism exists, as B. F. Skinner has shown in an experiment with pigeons, many years ago. I suggest that this very mechanism, random reward, may explain the evolution of homeopathy.

Martin Rundkvist, at Aardvarchaeology, has developed a nice theory which explains some aspect of this evolution. In brief: There is a selective pressure on altie medicine towards a null effect (1) because if it turned out to be effective, it would be classed as evidence-based, no longer as altie, and (2) because if it turned out to be harmful, it would be classed as dangerous and would be forbidden or abandoned. While this theory does a good job in explaining how an already existing altie method is being classified as altie, it falls short in explaining how it did evolve, how it survives extinction by lack of demand and by unwillingness of users to pay good money for nonsense, and how it even managed to invade the realm of university medicine.

B. F. Skinner’s random reward experiment

As a student of biology (university diploma in animal behaviour) I have been very fascinated when I’ve learnt of this experiment. Briefly, a Skinner box is a cage where animals such as rats and Read more

The Papanicolaou test has been designed for early detection of a virus-caused cancer, but it also improves the protection against this cancer and against other diseases caused by sexually transmitted viruses.

This unexpected protective effect of the Pap smear has been found in South Africa where hormonal contraceptives and cervical cancers have been studied in more than fifteen hundred women. Besides pap smears for detection of the cancers and the human papilloma virus (HPV) that causes them, the blood of the women has also been studied in order to detect other sexually transmitted viruses. It came out that not only HPV but also Herpes and HI viruses have been reduced in women who have received the most Pap smears.

It seems to be a clear relation of cause and effect: The more Pap smears, the less viruses, and the more recent Pap smears, the better the protection. For instance, a Pap smear in the previous year reduces the odds ratio of being infected by Herpes simplex virus versus being not infected by 60 percent; this reduction is only 20 percent if the last Pap smear is ten or more years back.

Even for HIV, a protection has been observed but, of course, relying on Pap smears and not using condoms would be a very, very bad idea.

Being cautious also reduces the risk

A pap smear seems to protect against sexually transmitted viruses, but how? The study cannot answer this question. Indirect actions cannot be ruled out. For instance, a “cautious” or “careful” lifestyle may be linked to more Pap smears on the one hand and to less sexual partners on the other hand, and the number of sexual partners is one of the major risk factors for sexually transmitted diseases. Thus, more studies are required to find out if the protection is really due to the Pap smear.

If you are fat, the worst thing you can do is having stress and sleepless nights from weight concerns and diet plans. And the best thing, according to a Korean study on sleep and obesity, may be just to relax and take it easy, having a good and long bout of sleep every night.

More than six thousand Koreans have been surveyed about their sleep duration, and their body mass indices (BMI) have been measured. It came out that the long sleepers tend to be slimmer than the short sleepers. Other studies in Iowa, Maryland, and in the NHANES survey have come to the same result.

This is not only a correlation but a causal link. The mechanism has been identified: Sleep increases the level of the satiety hormone leptin and decreases the level of the appetite hormone ghrelin.

Enjoy your Christmas cookies, and if some of them are heart shaped, you may take this for a symbol of a recent study result from Sweden. A possible association of sugar intake and mortality of heart patients has been assessed in more than four thousand established cases, and it came out that there is no such association.

This is good news for all who have heard all those sayings of sugar being bad for health. There is no reason for worries, at least when it comes to the heart. One of the things you can forget, for instance, is the glycemic index. The higher this index is, the faster is the uptake of sugar into the blood. No problem for the heart, the Swedish study says. Nor is the amount of sugar going to the blood, the glycemic load, of any importance for the heart.

Enjoy your Christmas cookies, and if some of them are heart shaped, you may take this for a symbol of a recent study result from Sweden. A possible association of sugar intake and mortality of heart patients has been assessed in more than four thousand established cases, and it came out that there is no such association.

This is good news for all who have heard all those sayings of sugar being bad for health. There is no reason for worries, at least when it comes to the heart. One of the things you can forget, for instance, is the glycemic index. The higher this index is, the faster is the uptake of sugar into the blood. No problem for the heart, the Swedish study says. Nor is the amount of sugar going to the blood, the glycemic load, of any importance for the heart.

The problem of obesity in old age may be due to a lack of fitness, but it remains unclear which is the cause and which is effect. Body mass index in elderly people has a serious drawback because, as people get older, muscles and bones (the fat-free mass) are being reduced and body fat mass is increasing. Thus, in spite of being weight stable, seniors may become “fat”. They may be better off adding weight and not losing muscle mass.

A new study has addressed this problem, analyzing fat mass and fat-free mass in seniors and their effects on fitness. More than nine hundred Canadian men and women between 67 and 84 years of age have been studied. Fat mass and fat-free mass have been measured by a special dual x-ray method. Fitness has been assessed by measuring walking speed and performance in the one leg stand test. It came out that fat mass is negatively linked to fitness.

Fat-free mass, on the other hand, is not linked to fitness - which is quite a surprise to me. Obviously, the fitness levels of all the study subjects have been high enough so that deficits did not (yet) emerge.

The old obesity paradox

Old obese often have been reported to live longer than old thin people. One aspect is easy to understand: a slow death is often preceded by weight loss. A second aspect is the diminishing accuracy of body mass index in old age given the shifts in fat and fat-free masses that may vary a lot between different people.

These two effects may offset possible bad effects of obesity in old age. It is not even possible to speak of an “effect” because we just have seen a link between more body fat and less fitness. Which one is the cause? A fat, heavy body with weak muscles is most likely a handicap to physical activity. But, on the other hand, a sedentary lifestyle may be the real cause that body fat is being accumulated and muscle mass is diminishing.

Key message: The role of obesity in old age remains unclear in many aspects, but this study shows a clear link between high body fat and low fitness. Given that fit old people live better and longer, fitness should be the main concern.