If your chameleon has even the beginnings of MBD then you are going to have to correct the imbalance as well as set up the proper supplementing schedule.
The quickest way to correct the imbalance is to get a vet to give it shots of calcium until the blood calcium levels are normal and the bones, etc strong again.
ASAP...start the phosphorous-free calcium powder at most feedings. this helps make up for the poor ratio of calcium to phosphorous found in most feeder insects.
Dusting twice a month with the phosphorous-free calcium / D3 powder ensures that the chameleon gets some D3 without overdosing it and leaving the chameleon to produce the rest of the D3 from its exposure to the UVB light.
Don't forget to replace your UVB light every six month sorry so.
It's also important to dust the insects twice a month with a vitamin powder that contains a beta carotene (prOformed) source of vitamin A. PrOformed sources of vitamin A cannot build up in the system and lead to overdoses like prEformed sources can and will leave it up to you to decide whether the chameleon needs prEformed or not (since there is controversy over whether a chameleon can convert it or not).
Appropriate temperatures allow for proper digestion and thus play a part indirectly in nutrient absorption.
Feeding / gutloading the insects is important too. Crickets, locusts, superworms, roaches. Can be fed a wide range of greens such as collards, escarole, endive, dandelion greens, kale, etc and veggies such as carrots, sweet red pepper, squash, zucchini, sweet potato, etc.
Water and cage setup are important too, of course.
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