Compared to the other tid-bits, this is rather frequent... it's frequent enough to almost not be in my list of tit-bits...
The phrase "with regard to" is used to indicate the subject that is being talked or written about. For example, "The department is reviewing its policy with regard to immunization." The word "regards," on the other hand, implies greetings. For example, "Give my regards to your family." Therefore, in the context of the following sentence, the word "regard" and not "regards" should be used.
Incorrect: These food products differ from each other with regards to consistency.
Correct: These food products differ from each other with regard to consistency.
[Word/Phrase Choice is a series of posts dedicated to the appropriate and gentlemannerly usage of some of the more peculiar words and phrases in the English language.]