There are many commonly-held beliefs around medicine and health, some of which are total rubbish.  But there are a few which hold grains of truth.  Here, I have listed a few popular ones and tried to explain how much truth there is before them.

1. Vitamin C prevents colds – sadly, false.  The common belief is that if you start to feel a cold coming on, and mainline vitamin C, you can stop it happening.  Either that, or eating plenty of vitamin C will stop you getting one in the first place.  There is a lot of conflicting evidence, but the generally accepted truth is it will at best make the duration of the infection shorter; if nothing else, your body will only absorb a certain amount of vitamin C, and the rest it will simply excrete.  The better defence against infection is to regularly wash your hands.
2. Antiperspirant causes breast cancer – happily, false.  There is apparently absolutely no evidence that there is any sort of link between antiperspirant and breast cancer, it just seems to be one of those tales that has cropped up from somewhere!
3. Having a slow metabolism causes obesity – false.  In fact, people who are obese tend to have faster metabolisms.  Individual variations such as how much you fidget can have more of an impact on how many calories you burn during the day, but obesity basically comes down to how much you eat, and how much you exercise.
4. Sitting at a desk all day is bad for you – TRUE! As if you even need to ask, if you have read my other articles!  Lack of movement, muscle wastage and even bone density decrease to list just a few problems.  Get up, move around – wander around as you talk on the phone, stand up to work if you can and even consider holding meetings where everyone stands (might make them shorter as well!).
5. Gluten-free is a healthier option – except in a few circumstances, false.  It’s a fad that has really hit the stage recently, but unless you are Coeliac there is no benefit to a gluten-free diet.  Gluten intolerance, in my experience, is also one of the most common self-diagnosed “allergies” as well resulting in many people are making their lives far more inconvenient – and expensive – than they need to.  Unless confirmed by a medical specialist, gluten may not be the spawn of evil it’s believed to be!
6. Warm milk helps you sleep – false, which was a surprise to me as well as many of you, I’m sure!  It would appear that apart from as part of a calming pre-bedtime routine, it doesn’t actually have a soporific effect at all.  Still tastes nice though.
7. Running on a soft surface is better for your body – true and false.  If you take up running slowly, the benefits of running on a soft or hard surface are merely different, not good or bad.  Soft surfaces make the muscles work a little harder and improve balance, while hard surfaces put a greater impact on the bones which (if introduced correctly) can actually strengthen the bones.  However, if you go straight into running long distances on a hard surface, or train in a way that is inappropriate for your current fitness level, it may well cause damage such as stress-fractures.  Long term, running on any surface (soft or hard) is also quite hard on the joints.
8. An apple a day keeps the doctor away – true.  Naturally, we are supposed to eat 8 portions of fruit and veg a day (yes, 8 not 5…don’t get me started on political reasons!), but apples are packed full of beneficial substances such as boron (good for bones), vitamins A, C and E, pectin (lowers glucose levels, cholesterol and maintains healthy digestive system), and antioxidants.
9. Coffee is bad for you – honestly? Erm – don’t know! Moderate consumption of caffeinated or decaffeinated coffee has been linked to a reduced risk of death from cardiovascular disease, diabetes and neurological conditions such as Parkinsons. However, a link like this isn’t proof of cause and effect – we can’t actually say coffee gives these benefits, or causes problems.  Other factors may have a much greater influence.
10. Drinking 2L of water a day is good for you – true.  Sort of.  Men are advised to consume up to 2.5L, women 2L, which makes sense when you consider the adult human is 65% water.  However, this includes the water you get from your food, as well as from all beverages.  In other words, you don’t have to make yourself drink bottles and bottles of water!
11. Cracking your knuckles causes arthritis – false.  One of my favourites.  How often have people who crack their knuckles been told they’ll end up with arthritis? The fact that they’re usually told this by someone who finds the noise very irritating may have something to do with it!  The actual noise does no harm at all, it’s just gas bubbles moving around.  Having said that the continual over-stressing of the joints required to produce the noise can cause problems such as tendonitis and possibly even arthritis later in life.
12. Tight underpants cause male infertility – false.  There is no evidence to suggest that if a man has a normal, healthy sperm count, tight underwear will cause problems.  It has been suggested, however, that if the sperm count is low or motility is poor, overheating from tight underwear might not help!

So there you have it.  A few interesting points, a few surprises – and all the fun of being able to correct your mates down the pub if they start discussing one of the myths!

(Article originally written by experts for the Benenden Be Healthy magazine)