Hair suddenly needs daily washing

[custardlover]

Since hitting my 40s my hair has just started to get limper and I have to wash it every morning now or it feels greasy and shapeless by lunchtime I used to be able to go a couple of days with a good blow dry! It's shoulder length with tinted roots done at the salon to cover my grey and I wash it daily with bedhead for coloured hair (shampoo and conditioner). I always blow dry. What am I doing wrong? Shall I change shampoo?

I know that hairdressers etc. recommend not washing every day but if you go on Philip Kingsley's trichology page they say you should. I am 47 with naturally greasy hair but it is coloured. Am also peri-menopausal and my hair has suffered as a result. I wash every day with good products. It's a pain and expensive but you 'wear' your hair all day, every day.
I have three shampoos on rotation otherwise my hair gets used to it. Every week I use Hairfix cleanser which gets rid of build up.