Let me get ahead of the marketing blitz and save you from making a wrong decision.
A study that was reported in the news yesterday and published in the American Heart and Stroke Associations' Journal - Stroke- found that those who ate more oranges and grapefruits - or citrus - had lower incidence/risk of clot related strokes. (the study summary can be read here)
This positive outcomes are related to consumption of the fruit itself.
This is not an affirmation of any type of supplementation. If you see an advertisement for a vitamin or food product which states that 'studies show flavanoids reduce stroke risk' - it does NOT mean that the product they are trying to sell you will do anything for your health. The study was NOT about pills or extracted chemicals.
Also - the scientists suggest that we avoid juices because of the high sugar content and the risk of diabetes associated with them.
The point is that something about the chemical properties of vitamin C in the actual fruits is health promoting. No other association should be made.
Good news - oranges are far cheaper than juices or supplements - especially if you have an orange or grapefruit tree in your backyard!
(note about strokes - there are two types, one occurs when a clot forms and stops oxygen flow the other is when there is bleeding or hemorrhaging - from a blood vessel. The results of this study were about clot related strokes)