Ahhh...okay. Reading Romans 14 it's obvious that the whole chapter has something to do with eating and drinking, not sabbath keeping. The word for sabbath is never mentioned.
So to keep the context of the chapter clear, it's necessary to determine what is it about eating and drinking that this verse could be referring to:
Romans 14:5, 6: "One person esteems one day above another, another esteems every day alike. Let each be fully convinced in his own mind. He who observes the day, observes it to the Lord; and he who does not observe the day, to the Lord he does not observe it. He who eats, eats to the Lord . . ."
Concerning this passage, Expositors Bible Dictionary says "The close contextual association as a time with eating suggests that Paul has in mind a special day set apart for feasting or as a time for fasting."
Certain jews fasted on specific days of the week. The controversy here was probably about those who fasted versus those who didn't, or possibly vegetarianism versus not. Either way it's about eating. The problem with most Christian doctrine is that they approach this verse with the supposition that since they don't believe in the validity of the sabbath, that this verse must be talking about that.