Not all vitamin A is created equal. There are actually two forms of vitamin A in the human diet, which are retinol (aka preformed vitamin A) and provitamin A carotenoids, such as beta-carotene. Even though popular nutrition literature often treats the different forms of vitamin A as equivalent, there are actually significant differences between the two. Retinol, which is also … [Read more...] about Food for Thought: Vitamin A