Regarding bone health...it's important that the nutrients be in balance...mainly calcium, phos, D3 and vitamin A. It's also important to provide UVB...and it should not pass through glass or plastic. Another important factor is the temperature.
Appropriate temperatures allow the chameleon to digest its food properly and thus play a part indirectly in nutrient absorption.
Exposure to UVB allows the chameleon to produce D3 which allows it to use the calcium in its system. As long as the chameleon can move in and out of the UVB it won't overdose on D3 from the UVB.
Since most feeder insects have a poor ratio of calcium to phos its important to dust the insects a phos - free calcium powder at most feedings to make up for it.
It's also recommended that the insects be dusted twice a month with phos - free calcium / D3 powder to ensure that it gets some D3 without overdosing it and leaving it to produce the rest from its exposure to the UVB.
It's recommended that the insects are dusted twice a month with a vitamin powder that contains a beta carotene (prOformed) source of vitamin A. This will ensure that it gets its vitamins without overdosing the vitamin A and leaving it up to the owner to decide how much prEformed vitamin A to give it....or whether to not use a prEformed source.
It's also important to feed/gutload the insects well. For crickets, superworms, roaches, locusts, etc. A wide assortment of greens ( dandelion greens, collards, endive, escarole, mustard greens, kale, etc ) can be used along with veggies ( carrots, squash, zucchini, sweet red pepper, sweet potato., etc).
Feeding a good variety of insects is also beneficial. You can use the one listed above as well as silkworms, butterworms and once in a while, waxworms.
To correct the MBD you should have a vet help you. You need to bring back a balance of nutrients and then use he information above to keep the balance to prevent the MBD from returning
