Spiders, Rain and Hair Growth


Yesterday, by accident, I killed spider.  And then it rained.  In fact, it poured. To some, this information will come as no surprise.  After all, it’s common knowledge to many people that killing a spider will cause it to rain.  But is it really true? Does killing a spider cause it to rain?  To the best of my knowledge there has never been a scientific study examining the relationship between spider killing and rainstorm patterns. 

As a hair specialist, I hear myths about hair loss every day and consider it an important part of my practice to spend time with patients to help separate fact from fiction.  When I’m asked if a specific product will help with hair growth, I generally respond with one of the following 3 answers:

Yes, there is good scientific evidence that this is likely to be helpful ...


I think this will probably help your hair, but there is only a small amount of scientific evidence for this claim  ....


There is no scientific evidence at present that this does anything to help your hair


Why do we need "scientific evidence"? 

If a patient says to me that a product helped them grows hair, then doesn’t it help grow hair?  Unfortunately, the answer is no. It's not that I don't believe what a patient might tell me. It's simply that there are too many reasons why a patient’s hair might have grown  - even if he or she were to put water on top. Certain types of hair loss conditions improve - even if you do nothing.

Let’s revisit the spider story again. There is no scientific evidence that killing spiders causes it to rain. To prove whether killing spiders causes it to rain, we would need to design a "scientific study" using 1000’s of spiders.   To design a really good scientific study, we would need to design a study with at least two big groups of spiders. In one group the spiders would be stepped on and in the other group they would not be stepped on. And then we’d check to see if it was more likely to rain on the days that spiders were killed. But is that enough of proof? The answer is still no! We’d need to make sure that all the spiders were the same types of spiders and that they were the same age of spiders.  (After all, maybe stepping on young 'garden' spiders causes it to rain but stepping on older 'house' spiders has no effect.) Furthermore, we’d need to make sure that the killing was done at the same time of year.  (Maybe stepping on a spider in the month of September causes it to rain but stepping on spiders in the month of May has no effect).  We would also need to clearly define where it is that we’ll be watching for the rain drops to occur.  (Perhaps killing a spider in Paris, France causes it to rain in Sydney, Australia).

You can see that if would cost a lot of money and take a lot of time to design a study to prove if stepping on spiders causes it to rain.  And so, the study has never been done.  Do we really 100 % know if killing a spider has anything to do with rainfall patterns in the world ? The answer is no. And that’s why I try to avoid stepping on them and continue to spread the myth to help other people avoid killing spiders too. But deep down, do I really think that killing spiders causes it to rain? The answer is, of course, no. 

Thousands of Hair Studies Needed

There are thousands of products on the market for hair and hair loss.  Some products have no scientific evidence that they help hair loss or help with hair growth.  They might help hair growth, but we simply don't know. Certainly, some products do help. To test if a product helps, it would cost money and it would take time.  When a patient tells me that a product helped with hair loss, I tuck the fact into the back of my mind but I usually don’t get very excited. When two different patients tell me that the same product helped them, I still tuck the information into the fact of my mind but usually don’t get very excited. When 10-15 people tell me about a specific product, I think about designing a small study or researching the evidence that this could be true. I remain aware of the possibility that it may be turn out that the product still offers no help for hair loss.

Sound Science Needed for Everything Consumers Put Trust In

This past week I learned that Reebok was made to pay 25 milliion dollars in customer refunds to settle charges of deceptive advertising of a specific type of shoe.  Previous advertising by the Reebok company had claimed the the shoe helped to strengthen and tone muscles.  The company had advertized that this specific shoe could lead to 28 percent more strength and tone in the buttocks, 11 percent more strength in the hamstring muscles and 11 percent more strength in the calf muscles than an ordinary walking shoe. The US Federal Trade Commision stated that it wanted national advertisers to realize that they need to excercise responsibility to ensure claims are supported by "sound science."


The Future of Hair as a Science

Some incredibly exciting hair research discoveries are taking place all over the world. Incredible people are doing incredible work. This means that new treatments for hair loss are waiting us in the years ahead. We need to always make sure that detailed and rigorous scientific research methods are used to help clearly define which treatments help individuals with hair loss and which do not.



Dr. Jeff Donovan is a Canadian and US board certified dermatologist specializing exclusively in hair loss. To schedule a consultation, please call the Whistler office at 604.283.1887

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