Cannell recommends 5,000IU.
From post #42: "The FNB concluded that serum 25(OH)D levels above approximately 125–150 nmol/L (50–60 ng/mL) should be avoided, as even lower serum levels (approximately 75–120 nmol/L or 30–48 ng/mL) are associated with increases in all-cause mortality, greater risk of cancer at some sites like the pancreas, greater risk of cardiovascular events, and more falls and fractures among the elderly."
>>Cannell recommends 5,000IU.<<
Actually, Dr. Cannell recommends 1,000 IU per 30 pounds of body weight, together with regular testing to ensure that you’re actually taking the right amount. I don’t recall him stating a specific range to achieve, but I doubt he would argue with 50-80 ng/ml.
In the case of an autistic child, he’s beginning to sound like a parent should shoot for the high end of the range to they determine whether it will help, even going as high as 100 ng/ml. His theory linking a vitamin d3 deficiency to the epidemic of autism we are now experiencing is quite interesting and is available on his website.