diff --git a/lib/i18n/backend/cache.rb b/lib/i18n/backend/cache.rb
index 41b58fc2..9f862169 100644
--- a/lib/i18n/backend/cache.rb
+++ b/lib/i18n/backend/cache.rb
@@ -21,7 +21,7 @@
 # configure your own digest method via which responds to #hexdigest (see
 # http://ruby-doc.org/stdlib/libdoc/digest/rdoc/index.html):
 #
-#   I18n.cache_key_digest = Digest::MD5.new
+#   I18n.cache_key_digest = OpenSSL::Digest::SHA256.new
 #
 # If you use a lambda as a default value in your translation like this:
 #
diff --git a/lib/i18n/backend/cache_file.rb b/lib/i18n/backend/cache_file.rb
index 4dafb3e6..0c5e1922 100644
--- a/lib/i18n/backend/cache_file.rb
+++ b/lib/i18n/backend/cache_file.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-require 'digest/sha2'
+require 'openssl'
 
 module I18n
   module Backend
@@ -19,7 +19,7 @@ def load_file(filename)
         key = I18n::Backend::Flatten.escape_default_separator(normalized_path(filename))
         old_mtime, old_digest = initialized && lookup(:i18n, key, :load_file)
         return if (mtime = File.mtime(filename).to_i) == old_mtime ||
-                  (digest = Digest::SHA2.file(filename).hexdigest) == old_digest
+                  (digest = OpenSSL::Digest::SHA256.file(filename).hexdigest) == old_digest
         super
         store_translations(:i18n, load_file: { key => [mtime, digest] })
       end