What degrades a supplement
Four things shorten a supplement's useful life: heat, light, moisture, and air. Controlling them is what keeps a product close to its labeled potency until the expiration date [1][2].
The worst spot is a common one
The bathroom medicine cabinet is a poor choice: showers create heat and humidity that accelerate breakdown. The cabinet above the stove is similar. A better home is a cool, dry, dark place — a bedroom drawer, a closet, or a pantry shelf away from the oven and window.
What belongs in the fridge
Not everything wants the same conditions [2]:
- Many probiotics keep best refrigerated — check the label, since some are shelf-stable.
- Fish, krill, and flax oils last longer cold, which slows the rancidity that makes them smell 'off.'
- Most vitamins and minerals do *not* need refrigeration and can actually be exposed to condensation each time a cold bottle is opened, so follow the label.
Simple habits that protect potency
- Keep the original container — it's designed to block light and moisture — and reseal it tightly.
- Leave the desiccant packet (the little silica gel sachet) in the bottle; it absorbs moisture. Gummies and effervescent tablets are especially humidity-sensitive.
- Don't decant a month of pills into a daily organizer far in advance if the product is moisture-sensitive.
- Mind storage standards — quality manufacturers test stability under defined conditions (USP references 'controlled room temperature'), which is what 'store in a cool, dry place' is approximating [3].
Don't forget safety and dates
- Store everything locked and out of reach of children (see [supplement safety for children](/learn/supplement-safety-for-children)).
- Respect expiration dates and discard products that have changed color, smell, or texture.