- A population might be exposed to a cold virus, but not everyone will display cold symptoms (in this case it is known as a sub clinical infection)
- Up to about 60% of this population will develop clinical cold symptoms (ie obvious cold symptoms)
- The conversion from having no symptoms to developing symptoms could be caused by being exposed to sudden blasts of cold as:
- Chilling of the body surface causes constriction (narrowing) of the blood vessels in the nose and upper airways
- This then lowers the local immune response in the nasal passage as the narrowing of the vessels reduces the blood flow/nutrient supply to the cells lining the respiratory tract. (Previous studies have focused on testing the systemic or ‘total’ immune system reaction rather than investigating a local immune response.)
- The nasty (!) rhinovirus which flourishes in colder temperatures then replicates and spreads throughout the respiratory tract and the individual develops the clinical symptoms of a cold.
Monday, 8 October 2012
I’m suffering from a stinking, lingering cold at the moment, and beginning to get tired of being told that I caught it because I don’t dress warmly enough or that I must have received a blast of cold air (un coup de froid) due to the changeable seasons. I have had this debate so many times with my French husband or during dinner parties (after lots of wine) and even at the school gates. ‘You simply can’t catch a cold from being cold. A cold is caused by a virus...’ and so on and so on. I have responded politely when little old ladies have scolded me for my children running around half naked in 10 degrees - “Avant nous habitions au Pole Nord, donc mes enfants ont l’habitude du froid!”. I have smirked when my doctor told me off for coming to his surgery with wet hair “Vous allez attraper froid, Madame Debeugny”. Priding myself on being a woman of science I have always been quick to state that there is absolutely no scientific evidence to prove that ‘being cold’ lowers one’s immune system.....!
But, I am now possibly prepared to admit that I might be wrong. Is there something to this old wives' tale after all? Is there a link between cold exposure and developing a cold? Why do some of us get colds and not others despite being exposed to a cold virus? How? Study after study has failed to find a link between cold exposure and immune system function. I then came across this little gem of a paper which I think could explain quite effectively the hows and whys. The theory goes like this:
So, there you go. It’s a theory only and has not been tested, but I think it’s an interesting one. I humbly promise that I will stop trying to be a smug know it all and will check my facts carefully in the future. It does not quite explain why my three children are able to run around barefoot in the garden in all temperatures and not have permanent colds. Possibly because their super nutritionist mother stuffs them full of good healthy food....?!
(The reference for the paper, if you want to have a look is Eccles R (2002) Acute cooling of the body surface and the common cold Rhinology 40 109 - 114)
A little gem of a recipe, baked almond custards which I served with a plum compote. Just perfect comfort food when you are feeling under the weather..!!
600 ml almond milk
30g brown sugar
50g flaked almonds
2 large eggs
20g soft brown sugar
1 tablespoon cornflour
1 vanilla pod
1 good glug of amaretti liqueur (and a glug for you!)
Heat oven to 150 degrees. Place 4 greased ramekins in a deep baking tray which is filled with water, so the water level reaches half way up the ramekins. Dry fry the almond flakes and the soft brown sugar in a frying pan until just turning golden and caramelised Take off the heat and place in a dish (if you leave them in the pan they'll carry on cooking).
Heat almond milk with the vanilla pod and leave to infuse for 10 minutes. Beat the eggs, cornflour, liqueur and brown sugar together. Remove the vanilla pod from the milk (let it dry and then you can reuse it). Pour the warm milk onto the egg mixture, beat throughly to mix and then pour into the ramekins. Bake for 30 minutes. Serve warm and decorated with the caramelised almonds.