Freshness Disclosure Act of 1999 - Amends the Federal Food, Drug, and Cosmetic Act to provide that a food shall be deemed to be misbranded unless it is labeled for freshness. Requires the label to state a date upon which the food will no longer be fresh (i.e., contain the quantity of nutrients specified on the label and otherwise be not adulterated and of acceptable quality). Requires such date to be preceded by "best if used by," and requires such label to be conspicuously located, easy to read, and in a type size no smaller than eight point.