He is the Co-founder and Chairman of O'Leary Funds and the co-founder of Softkey. He has also previously served as a business journalist on CBC 's The Lang and O'Leary Exchange with Amanda Lang and hosted Redemption Inc.ailed as Canada's business equivalent of Donald Trump, O'Leary is one of Canada's most prominent entrepreneurs, investors, and financial pundits.
When calcium is low and/or a person has symptoms of vitamin D deficiency, such as bone malformation in children (rickets) and bone weakness, softness, or fracture in adults (osteomalacia), 25-hydroxyvitamin D usually is ordered to identify a possible deficiency in vitamin D.
The Vitamin D Council considers optimum levels to be approximately 50 nM/L. The 25-hydroxyvitamin test measures the amount of calcidiol (a prehormone found in the blood that is produced in the liver). This is considered the most reliable form of testing for Vitamin D deficiency.