'People with the best voice always smoke!' Adele complains that her decision to quit smoking has left her with 'weaker' vocal abilities
We know that smoking thickens and dries out vocal folds. We also know that Adele did suffer a hemorrhage which was then surgically removed. Either/both of these things can cause a change in how it feels to produce the voice after they are over.
The good news is that she is still young in terms of vocal age which allows for a greater degree of flexibility of the tissues and bouncing back. The bad news is that some of this natural flexibility may have been reduced already because of the above incidents and will likely continue to deteriorate as cartilages ossify (stiffen) as one ages.
Best to avoid the smoking habit altogether...
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