My name is Joe and yes, IBJoe means I work for Fitday.com
I'm the lead developer and I'd like to get to the bottom of this.
If we take, Vitamin C for instance.
There is the percentage of the Daily Allowance that is pre-supposed. That's just part of the Food. A custom food could claim that it contained 100% of the Daily Allowance of Vitamin C and that could be false.
So, there are the percentages that are stored with foods both built-in and custom that are never 100% correct.
Then separately there is the actual value of Vitamin C of that this supposedly correct food say, 75 milligrams, contains. Again, this number is essentially correct or false based on the accuracy of our database and the accuracy of custom foods defined by YOU.
Then as a third percentage there is the percetage of the Recommended Daily Allowance (RDA) that this 75 milligrams represents.
Now, the RDA is sensitive to Age and Sex, so it's different for large segments of the population.
With that basis of understaning. Let's discuss some specific cases of foods ( built-in or custom ) and show some screen shots ... and have some geeky time with Fitday.