Common Factors:

1. Recent fillings
2. Recent nasty cold and round of antibiotics
3. Recently became fully vegan (from vegetarian) and dramatically lowered my salt intake, increased all fruit intake (including berries, which I saw mentioned) and protein intake - on the "Eat To Live" diet
4. Have had bells palsey early in life
5. Don't drink coffee
6. Don't drink alcohol
7. Don't smoke
8. Don't take anything other than a daily vitamin
9. Not taking meds at all

I'm 30 years old and have experienced a bad taste in my mouth for 4 days that today became an insanely salty taste. Good luck finding the problem!!! I'm not going to see a doc because I don't think it will help. My gut feeling is that its either diet related or cold/infection related.