Moderation in all things. A little bit of sugar, fat, carbs, and salt in your
diet isn't going to be bad for you. In fact, I think these wild diet changes are probably worse. I know a lady who cut out all sweets this year - absolutely no processed sugar starting on January 1st (much like Slim is talking about here). It looks like she has gained weight this year.
Follow the Word of Wisdom, eat a balanced diet, and get some exercise and you'll be fine.