Duh. Obviously they cool. Not so quick. New Australian medical research warns that when temps are dangerously high and humidity is low, fans can actually make a person feel hotter, increase strain on the heart and raise core temperature. That would mean that then, fans are not only unhelpful to protect our body (brain!) against overheating — they would work counterproductively and then be dangerous.
The good news is that this is not just counter-intuitive — it’s plain nonsense. I could write 10 blog posts a week just exposing medical ‘news’ that is neither. Because I live in dry Jerusalem, I picked this one.
There are two heat values in our body, our skin temperature and — more deeply — our core temperature.
Our Core Temperature
The core temp needs to be 37 Celsius unless we want to get rid of microbes that function and multiply best at 37 — then we make a fever of a couple of degrees while the immune system revs up to clear the body.
When our core temperature falls a few degrees between normal, many biochemical processes slow down significantly.
But when our brain temperature comes close to 42 Celsius, irreversible brain damage is to be expected, eventually leading to death.
Our body can raise the core temp by burning (oxidation of) bio-fuels (from food or stock or, in an emergency, even body parts like muscles). This comes on top of our basic metabolism that already produces heat. Much muscle activity also produces more heat — thinking hard doesn’t.
Our Skin Temperature
The main way we cool our core temperature is through the skin. There are several ways but they all make use of leading the too warm blood through blood vessels in cold skin tissue. How to cool our skin?
Being in colder water of air can cool our skin. But also water on the skin that evaporates produces cold — the idea behind perspiration.
And we can shade ourselves from heat influx by staying in the shade or in a colder environment.
This is all simple but there are two complications:
1. We feel our temperature in the skin. This is problematic because the essential temperature to guard, our core concern, is our core temp. This can be confusing. Compare someone getting a fever. What then happens?
The body will burn extra bio-fuel and contract the skin’s blood vessels to prevent it from losing heat. So, we feel cold: our skin became less than 37 Celsius. But our core temp is rising. “I’m so cold.” The experienced parent says: “Are you getting sick?” After a couple of hours, the core temperature is high enough and the blood vessels in the skin open up. “I’m so hot.” The experienced parent says: “I think you’ve got a fever.” (Though, children with a fever often report a headache, not feeling hot.)
2. The skin and our core temperature needs don’t always jive.
When our skin gets too cold from a very cold surrounding, the blood vessels in it close. Cold skin becomes whitish. This reduces heat loss which is nice for our core temp but not for the skin that may freeze and die.
When our skin gets too hot (the sun shining on it), the blood vessels in the exposed skin open up. This transports a lot of heat to our core so it might overheat. But our cooler blood might reduce sunburn. Blood vessels our shaded skin are then open too and sweating makes that part of our skin even colder to try to cool down the body as a whole.
3. So, local skin condition, more than core temperature needs, mostly determines what the skin does though protecting our core temperature should get priority.
When we cool the skin of an overheated person too much, the blood vessels in it close. Then they listen more to normal local needs than to what the core needs in an emergency. Normally, we don’t want to lose too much heat, so, cold closes the skin’s blood vessels.
Therefore, a person in danger of a heat stroke must never be put in a cold bath. That closes the blood vessels, the body can’t lose heat anymore, the core temp goes up and the person dies. A bath or sprinkling of 35-36 Celsius water is best.
Fans in Hot Dry Air
Now, let’s go to our ventilators on a hot day. They should help perspiration to evaporate faster so that we cool down more. But a steady stream of air and evaporation close the skin blood vessels and we don’t cool down. We may feel cooler (in our exposed skin) but overall, our temp goes up if anything and the skin not blown at feels hot too.
But that’s why there are ventilators that swerve or that change their speed from fast to slow and back all the time. This gives the skin the chance to warm up, open its blood vessels so that the effect of the perspiration can cool down the blood flow, just before the next boot of air encourages evaporation again and the greater cold closes the vessels.
They don’t swerve to be social and have everyone profit nor are designed by crazy technologists who don’t want us to enjoy fans all the time!
The Australian researchers don’t write about swerveling fans. To the contrary. They write that the same must be true for ceiling fans. That don’t swerve. They must have used steady-stream fans. In dry air, they make the skin too cold to help cool our core. They actually make us hotter. Nothing to do with the fan blowing air that’s too hot.
Basic human physiology, overlooked by an associate professor in the faculty of health sciences and director of a university thermal ergonomics laboratory.
Bonus: Weekly intercourse after heart attack is not found life-saving
That should be the proper conclusion — admitted to in the last sentence of the Reuters report titled: ‘Weekly sex could boost survival among heart attack survivors.’ The rabbis know for a thousand years already that sex is healthy. But obviously, people who are in bad health will on average have less intercourse. They also found that people who have less intercourse also do less exercise — but the sex is in the headline, not the workouts. People in an intimate relationship have a greater chance to survive and to have intercourse. Older people with intercourse more than once a week might be more often sex-addicted single people who have sex with multiple partners which is a health risk — so, less protected. Why the researchers only considered intercourse sex is unclear. What is clear is that they made the papers again with a disguised non-finding.
Bonus 2: There is no checking to help prevent Alzheimer’s
And that should have been the headline instead of the nonsense report ‘Hadassah rolls out non-invasive brain test to help prevent Alzheimer’s.’
The real news is that they’re going to check how much silent brain damage people have without opening up the skull (which is not the same as the non-aggressively sounding ‘non-invasive’: they will inject radioactive stuff and flush the brain with radiation).
There is no known cause for dementia, so chances for prevention are elusive. Therefore, the test will need to be paid for by the naive patient who can be made to believe that knowing can lead to stopping the illness. The medical advisors of the health ministry obviously couldn’t be fooled.
This still on top of the fact that some people with severe physical brain damage can have no symptoms at all while there are people who are severely brain-damaged without any radiological signs of damage.
Bonus 3: Researchers can now delay menopause by up to 20 years
In ‘Researchers say they can now delay menopause by up to 20 years,’ menopause is talked about like it’s an illness or injury.
The reporter is conjured up the idea that “Menopause typically is accompanied by mood swings, hot flashes, a lowered sex drive, and the development of medical conditions such as osteoporosis.” Only the last point is true. The others are just symptoms of the onset of menopause.
This procedure is new, so: risky, and extremely expensive, uncalled for.
The real decoy here is the promise that the sex drive will not decline. Straight men full of sex drive and sexism will love this news. Truth is that women generally are less plagued by a sex drive. Vaginal dryness can be remedied with a little cream. No need to risk one’s health and wealth.
Bonus 4: It is not clear if exhumes from heavy traffic give cancer
Headed ‘Do Israel’s congested roads increase cancer risks?‘ we read that researchers found that heavy-traffic exhaust gasses penetrating the home can give 50% more prostate, long or breast cancer. Older people are 80% of the time at home so knowing their situation at home counts.
Yet, lung and breast cancer take decades to develop until they are can be detected and kill. So, in the years they got cancer (undetectable still), these patients didn’t spend 80% of their time at home. And almost all older men have non-aggressive prostate cancer so that should not be in the equation at all.
Besides, a third of these people surveyed died within nine years. That’s so high that an added risk of 50% becomes meaningless. In the individual case, there is no great difference between a 33% and a 50% chance to die.
Last but not least, a third of the people followed smoked. Wouldn’t smokers and the tobacco industry love to hear that pollution outside the house was more damaging to health than smoking cigarettes. Instead of ‘correcting’ the statistics for the risks of smoking, they should have looked if smoking and air pollution compound each other’s damage.
Bonus 5: The end of cancer seems possible
To end on a positive note: There is some progress in preventing and killing melanoma cells through vaccination. The article notices that this approach, if it works, will become available in ten years. (Another report about the same news leaves this significant caveat out and peddles pop theories about the development of cancer. Cancer cells don’t grow faster. Rather, they “forget” to die when normal cells do. There are even reports that this vaccine works. Terribly false.) It doesn’t (can’t) promise that it would work for all cancers. But it gives realistic hope.
It should have noted that most people are cured from melanoma by going to the doctor in time when they see some strange pigmentation.
Overall conclusion: be a total skeptic about any medical research news!