diff --git a/brood/src/data.rs b/brood/src/data.rs
index c994d66..3c75122 100644
--- a/brood/src/data.rs
+++ b/brood/src/data.rs
@@ -120,6 +120,22 @@ pub struct AdjacencyList {
 
 impl AdjacencyList {
     pub fn check_consistency(&self) {
+        // Check that all types are large enough
+        assert!(self.pages.len() <= u32::MAX as usize, "pages len");
+        assert!(self.links.len() <= u32::MAX as usize, "links len");
+        for page in &self.pages {
+            assert!(page.link_idx <= u32::MAX as u32, "page link_idx");
+            assert!(page.id <= u32::MAX as u32, "page id");
+            assert!(page.length <= u32::MAX as u32, "page length");
+            assert!(page.title.len() <= u8::MAX as usize, "page title len");
+        }
+        for link in &self.links {
+            assert!(link.to <= u32::MAX as u32, "link to");
+            assert!(link.start <= u32::MAX as u32, "link start");
+            assert!(link.end <= u32::MAX as u32, "link end");
+        }
+
+        // Check that all links contain valid indices
         let range = 0..self.pages.len() as u32;
         for link in &self.links {
             if !range.contains(&link.to) {