Wrong. When God says the sky is blue, it's no more valid than when the nutritionist says it; it's called "truth."
You're trying to make truth relative.
And by the way, when you say God said something He DIDN'T say, you're taking the Lord's name in vain.
So eating a vegetable because someone says it’s good for you is the same as heeding what God says about His Word. Gotcha! If you have an allergy to that vegetable, it is still good for you? Some Catholics must have an allergy to God’s Word.
And what was that?