3 Not So Great Things You Need to Know About La Croix 1. The claim "natural flavoring" claim might be questionable. "Natural flavors" can sometimes include preservatives. LaCroix, according to their website, does not include artificial ingredients. Plus, dietitians are concerned the flavors could create frequent cravings for the drinks. 2. Carbonation has it's downsides. First off, carbonation is not great for your teeth. Secondly, it might increase appetite which can lead to weight gain. 3. BPA contamination could be a risk. BPA-based plastics are used to line food and drink cans to protect against metal contamination. It may cause thyroid and metabolism issues, irregular periods, and changes to your mood, energy, or fertility. The FDA says BPA at it's current level is safe, but it can't hurt to drink the La Croix products sold in glass bottles.