Insulin Resistance and Cushings syndrome?

Dear Dr. Dan:
According to attached website, soy is not a beneficial product for insulin resistant horses.  Can you explain why your products contains it? The site also recommends chromium for insulin resistant horses..
I have a horse that has a cresty neck, gains weight and has allergies to cullicoides and certain feed, so I took care of feed part  , he only gets plain crimpted oats, grass hay and pasture and some of the bugs..  I am using your Redcal, health check powder and oil, just add oats, bug check. From using your products for the past year or so, his coat is shiny, it helps some,  but he still bites himself and has scaby skin on chest, belly line, mane, tail & face and cresty neck. This is a very costly horse, not sure how long I can afford him. What else can I do for this horse that is less costly and beneficial?  He’s only 6 years old and had this for past 3 years. I haven’t vaccinated him at all this year and hasn’t gotten any medication ever except a couple times or so a couple years back when we needed to tranq him to flush a hemetoma in his leg and power float his teeth. 
Do you have biting no see’ms, black flies and midges in TN?
I have 7 horses at our farm, he is the only one that has the problem, he was raised in Ky came to CT in Sept of 2004 in top condition, no allergies or skin problems. 
I use BTI and fly preditors on our property, but neighboring properties don’t. Lots of water around here.  They have run-in shelters with fans.  In there dawn at dusk when bugs are feeding.
Thanks for listening.

Marianne F.

All a matter of opinion.  My 10years+ using it with the results we get proves it for me. (We have seen literally hundreds of cases of fat overweight cresty necked IR horses)

See the article on fats in the magazine and search . Also remember that horses are NOT the same as people. Listen to our audio on “what to feed your horse” also. Good fats are just part of the solution. Yet VERY important indeed!