I have been diagnosed with insulin resistance and have been eating appropriate foods and am still extremely di?

I am 34 and have just been told i am insulin resistant and i need to avoid all sugar, fatty food etc and need more exercise as i am 90kg. My fasting serum insulin is 36 mU/L but my sugars are fine and well within the normal range. I am very confused and no matter how much or how little i eat i am constantly dizzy ? if anyone has suggestions or is in the same situation please let me know ?