Absolutely to both!
Women with very thick hair may need to have their hair thinned out in order for the style to not look overly large and poofy. Styling with a flat iron and a smoothing serum (like Sexy Hair's Frizz Eliminator) may be desirable to keep the fullness to a minimum.
Women with very thin hair can also wear a stacked haircut. Minimal texturizing may be necessary to give the style some lift at the crown of the head. I recommend that women with thin hair and a stacked bob learn to blow out their hair with a roundbrush to give the style fullness and lift. It's also important to find the right volumizing products that won't weigh your hair down (I recommend CHI's Volume Boost).
Photo © Kendra Aarhus
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