Storing Nuts
The Healthy Bird Cookbook by Robin Deutsch
Chapter 2; The Food Groups - pg. 39
Nuts
Except for acorns, birds love all kinds of nuts. They have different degrees of fat content, so use moderation when supplementing with nuts and also make sure they are unsalted. Remember that certain nuts such as pecans are polished nuts, which contain dyes. If you can find unpolished nuts, these are much better for your bird. They are hard to find and do not look very pretty, but they are worth the search....
Chapter 5; Foods to Avoid and Other Hazards - pg. 76
Nuts
Even nuts such as Brazil nuts and almonds can cause problems for your bird. This is especially true around the holiday season when imported nuts are polished and also dyed. Most birds do not ingest the nut shells, but some birds may. The dyes in these nuts are hard to digest, so when birds eat these nuts, they may end up with impacted crops, which can lead to death. When buying nuts for your bird, buy from sources you can trust. Even imported nuts are safe as long as no dye has been added to them.
Chapter 5; Foods to Avoid and Other Hazards - pg. 78
Food Dyes
Many foods today have dyes added to them to make them more appealing to the eye. This is also true in bird foods.
Many food colorings are synthetic and are not natural. Synthetic food colors are sometimes derived from petroleum or coal tars. In high doses, these food dyes have caused cancer in lab rats. They are also linked to allergies and even behavioral disorders. According to the FDA, different dyes can cause different problems.
Red dye #3 has been linked to thyroid tumors, chromosomal damage, and hyperactivity. Red dye #40 has been linked to lymphatic tumors and hyperactivity. Blue dye #1 has been known to cause chromosomal damage, while blue dye #2 has been linked to brain tumors. Green dye #3 can cause bladder tumors. Yellow dye #5 has been known to cause thyroid and lymphatic tumors, allergic reactions, and hyperactivity, and yellow dye $6 has caused kidney tumors, chromosomal damage, and allergic reactions.
It is best to use natural dyes in your birds food (and in your diet as well).