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.
There are numerous problems with regularly measuring serum vitamin D levels to assess for deficiency.1 One issue is the lack of standardization in the screening process. The accepted test is to measure levels of 25-hydroxyvitamin D because of its half-life of three weeks.