Yes, silverfish eat books. They feed on the starch in bookbinding glue, the cellulose in paper, and the sizing agents used in book production. A silverfish infestation can cause real, visible damage to a book collection over time, leaving irregular holes, surface scraping, and yellowed or thinned pages.
What Silverfish Actually Eat in Books
Silverfish are attracted to carbohydrates, particularly starches and sugars. In a book, that means several components are on the menu. The paste and glue used in traditional bookbinding is a primary target, since older adhesives were often starch-based. The paper itself contains cellulose, which silverfish can digest. They also consume the sizing agents applied to paper during manufacturing to make it smoother and more receptive to ink.
The damage typically appears as irregular holes or notches along page edges, surface grazing where thin layers of paper have been scraped away, and loosened bindings where glue has been consumed. You might also notice tiny dark specks of frass (droppings) or small yellowish stains on pages. Older books are especially vulnerable because their materials tend to be more organic and starch-heavy than modern publications.
Silverfish don’t limit themselves to books, either. They’ll eat wallpaper paste, cardboard, photographs, stamps, cotton and linen fabrics, and even some synthetic fibers if they contain starch-based finishes. Anything with cellulose or starch is fair game.
How Silverfish Infestations Grow
Silverfish are nocturnal and avoid light, so an infestation can be well established before you notice it. They thrive in humid environments, requiring moisture levels above 50% to survive and reproduce comfortably. Dark, undisturbed spaces like bookshelves, storage boxes, basements, and closets are ideal habitat.
A female silverfish lays eggs in clutches of seven to twelve, with up to 30 eggs at a time. Eggs hatch in 20 to 40 days depending on temperature, with warmer conditions speeding things up. Under optimal conditions, silverfish can live up to four years, molting continuously throughout their lives. That long lifespan combined with steady reproduction means a small problem can quietly become a large one.
Silverfish Damage vs. Other Book Pests
If you’re finding damage to your books, silverfish aren’t the only possible culprit. Firebrats, which are close relatives, cause similar damage but prefer hotter environments like attics and areas near furnaces. Carpet beetle larvae can also damage books, though they tend to target the fabric components of bindings rather than paper.
Booklice are another common find near books, but they’re actually far less destructive. Unlike silverfish and firebrats, booklice don’t directly damage paper products or fabric. They feed on microscopic mold that grows on paper in humid conditions. So if you’re seeing tiny, pale insects near your books but no physical damage to the pages, booklice are the more likely suspect. Silverfish damage, by contrast, is unmistakable: you’ll see material that has clearly been eaten away.
Silverfish themselves are easy to identify. They’re roughly half an inch to three-quarters of an inch long, teardrop-shaped, and covered in silvery scales. They move in a distinctive fish-like wriggling motion and have three long tail-like appendages at the rear.
How to Protect Your Books
Humidity control is the single most effective thing you can do. Silverfish need moisture above 50% to thrive, so running a dehumidifier and targeting 40% relative humidity in the room where you keep books makes the environment hostile to them. This one step does more than any trap or repellent.
Beyond humidity, a few practical habits go a long way. Pull your books off the shelves every few months and wipe down the surfaces. Silverfish prefer undisturbed spaces, and regular cleaning disrupts their habitat. If you buy secondhand books, quarantine them before adding them to your collection. Sealing them in a plastic zip-lock bag and placing them in the freezer for several days kills both silverfish and their eggs.
For active infestations, food-grade diatomaceous earth is widely used and effective. It’s a fine powder made from fossilized algae that damages the waxy coating on insect exoskeletons, causing them to dehydrate. It’s nontoxic to people and pets but lethal to silverfish. Dust it into crevices, along baseboards, and behind bookshelves where silverfish travel. Glue traps placed along walls and near bookshelves help monitor and reduce populations as well.
Natural Repellents
Several strong-scented materials act as deterrents. Cedar blocks placed behind or between books on shelves are a popular option. Whole cloves scattered on shelves and refreshed once a year have a good reputation among book collectors. Bay leaves, lavender sachets, and dried neem leaves tucked among books also help repel silverfish. Some people wipe shelves with cedar or eucalyptus oil, or place unwrapped bars of plain soap (like Ivory) on shelves, which silverfish seem to avoid.
These repellents work best as a complement to humidity control and cleanliness, not as a replacement. If your storage environment stays warm and damp, no amount of bay leaves will keep silverfish away from a shelf full of old paperbacks.
Which Books Are Most at Risk
Older books with traditional starch-based bindings and uncoated paper are the most vulnerable. Rare books, antique volumes, and anything with natural fiber components should be stored in climate-controlled conditions if possible. Books kept in cardboard boxes in basements or garages face the highest risk, since those environments combine darkness, humidity, and minimal disturbance.
Modern mass-market books printed on coated paper with synthetic adhesives are less appealing to silverfish, though not immune. If silverfish are hungry enough and conditions are right, they’ll eat nearly any paper product. Storing valuable books in sealed plastic containers with silica gel packets or moisture absorbers adds an extra layer of protection, especially in humid climates.