How should the capsules be stored, and what should you watch out for when using them?

Ascorbic acid breaks down when exposed to light, high temperatures and moisture. This means that where you keep it matters: a windowsill, a shelf above the cooker or a humid bathroom is not the best choice, even if the pack is closed.

The ideal conditions are a dry place at room temperature, protected from direct sunlight. A fridge is generally not needed for capsules in sealed packaging unless the manufacturer states otherwise on the label.

• Close the pack tightly after each use — contact with air and moisture speeds up oxidation.
• Do not transfer the capsules into other containers unless necessary, especially metal or transparent containers without protection from light.
• Keep an eye on the expiry date — once it has passed, the concentration of the active substance may decrease, even if the capsules look normal.

When travelling, it is convenient to take only the number of capsules you need in a small dark container rather than the whole pack — this reduces the risk of damaging the rest of your supply through changes in temperature or humidity on the road.