How Much Vitamin D Should You Take? 4.83 (96.67%) 30 votes The safe dose of vitamin D supplementation to get most of the population to the optimal level is 2,000 IU a day, but the elderly and overweight may need more.
roadblock. 1  n any condition that makes it difficult to make progress or to achieve an objective. 2  n a barrier set up by police to stop traffic on a street or road in order to catch a fugitive or inspect traffic etc.
The world of foreign relations is tricky to navigate. Roadblocks include differences of opinions, cultural and religious barriers and economic and military interests that are at odds. Sometimes, though, two countries form an alliance that is mutually beneficial, such as in a bilateral cooperation agreement.