Many commercial nesting materials are actually made up of very small threads or fibres. These threads can sometimes get wound around little hamster toes and cause injuries. Also, if your hamster eats some of these bedding, the fibres may not be digestible. While the risks are small, there are easier alternatives.
Economical Nesting Materials
Simply use undyed and unscented toilet paper, facial tissue, or soft paper towels. You can shred these a bit but you can let your hamster finish shredding them and crafting them into a soft cozy nest.
About Cleaning the Nest
A hamster's nest is his or her home-base and disturbing the nest can cause some stress. When cleaning the cage reuse some of the cleanest parts of the old nesting material as a base for the new nest, as this will offer security to your hamster. Hamsters do sometimes hoard food in their nests, so it is a good idea to do a quick check on the nest after feeding any perishable treats to remove any bits that your hamster may have stashed away for later.
Nesting Material vs Bedding Material
The distinction can be a little confusing. Generally, bedding the material you place in the bottom of the cage, such as aspen shavings or any other alternatives to cedar and pine shavings. Nesting material is the material your hamster will take into his or her favorite hiding spot to line the nest in which the hamster sleeps.