High humidity present in bathrooms and kitchens could degrade the vitamins and health supplements stored there, even if the lids are on tight, a Purdue University study shows.
Lisa Mauer, an associate professor of food science, said that crystalline substances – including vitamin C, some vitamin B forms and other dietary supplements – are prone to a process called deliquescence, in which humidity causes a water-soluble solid to dissolve. Keeping those supplements away from warm, humid environments can help ensure their effectiveness.
“You might see salt or sugar start to cake in the summer, start to form clumps, and that’s a sign of deliquescence,” Mauer said in a press release. “You can also get chemical instabilities, which are a little more problematic if you’re consuming a dietary supplement with vitamin C for that vitamin C content.”
Mauer said storing vitamins or supplements in containers with lids in humid rooms does not always help.
“Opening and closing a package will change the atmosphere in it. If you open and close a package in a bathroom, you add a little bit of humidity and moisture each time,” Mauer said. “The humidity in your kitchen or bathroom can cycle up high, depending on how long of a shower you take, for example, and can get higher than 98%.”
Storing products in dry conditions, can avoid unwanted ingredient loss.
Mauer suggested discarding any dietary supplement that is showing signs of moisture uptake or browning.