The white dots are usually indications of a split caused by damage or dryness. Since It appears you are taking good care of your hair, the cause is probably dryness.
You might want to try using a drop or two of mineral oil (baby oil) on the ends to help combat dryness. For ease of application, try this method:
Put 2 or 3 small drops of MO in a small dish, then take a cotton swab and coat it with the oil. Then take the swab and cover your palms and fingers with the oil. Then run your palms down through your hair several times until the sheen has vanished from your palms. Be sure not to use too much baby oil.
MO is lightweight and does not leave any odor. It is easily removed upon the next shampoo. It also helps combat frizzies and is a great detangler. As with all things, it does not work overnight..and it works best on hair that has been clarified first. Use it on DAMP, not dripping wet hair. You can also use it on dry hair..but damp hair seems to be best. Many LHCers have used MO with great results.
By the way, the mineral oil should only contain MO plus a fragrance. Additives may cause breakouts.