It will not help against the 'metal' taste but be sure to clean your bottle from time to time. I use a stainless steel bottle for water exclusively and they start to get funky after sometime.(keeping water in the closed bottle for more than a day is usually enough, but the funky ness is exaggerated for context) Fill it with boiling water, let it sit for a few minutes, then empty and let dry is usually enough to clean it. Like others have said, don't put protein like milkshakes or similar in the bottles. If it's a water bottle, it should be for water exclusively