Is there such a product that provides protection from blowdrying and heat styling while actually improving the condition of my fine straight hair without weighing it down? Is there an end all be all for this big request?
The brains have some suggestions here: thebeautybrains.com/2008/04/29/how-to-protect-your-hair-from-heat-damage/
I have fine, straight hair and use the Tresemme heat tamer spray. I don't know if it improves the condition of my hair (I think the best you can hope for from a product like this is to protect it from further damage) but it doesn't weigh my hair down. I use a shine serum too, which will weigh it down if I use too much, but I can use both if I'm careful with the serum.
I tried Tresemme's spray and didn't care for it...my hair got extra frizzy and just poorly behaved when I used it with blow-drying, but it works great for flat-ironing. I switched to Dove's heat spray and I'm liking that loads better to protect my hair from my dryer (since this is where most of my damage comes from -- I don't flat iron often). It says it conditions...it definitely helps with frizz. The sprayer stinks though...I spray it in my hand first then work the product through my hair. Either way its under $5 each to check them out. =)
I don't know if this helps from heat, but I had a cellophane treatment done on my hair and it's improved the overall condition of my hair, and it helped keep my highlights vibrant longer. I just get a clear coat on after my highlights are processed.
I think the cellophane treatment helps seal my cuticles, so my hair in general appears shinier, and it feels softer. I do blow dry, and so far, my hair still feels soft.
BUT, I do also use super heavy duty conditioner AND leave-in conditioner on a daily basis.