If it lasts a week its a cold. Sensitivities/intolerance's are a real pain and can reduce mobility but unlike true allergies which have an immediate reaction they hardly ever carry you off. (immunologist)

Have you had your Vit D levels checked recently? I had a bad spout of colds after my daughter was born but my GP dismissed it as "normal after having a baby". A blood test revealed a severe deficiency. I take a supplement now and the length and severity of colds seems to be back to normal.

Hmmm...I haven't noticed this after I started treatment. There were definitely times before being diagnosed/treated, where they seemed to drag on forever -- but part of that was undoubtedly just low thyroid fatigue which I mistook for my body fighting a cold (I also had super low vitamin D before treatment so that may have been part of it too). Since treatment and supps, they seem pretty normal now.

I have Hashi's and used to get a couple bad colds a year that would last up to a month. They were so hard for me to get over. No doctor ever gave me any official reasoning, but I think it was because I was later found to be severely deficient in vitamins D and B. I had to give myself B injections and take an rx strength D supplement to get back up to normal. I now take a daily multivitamin (plus my yearly flu shot) and have been completely cold free for a couple years.