Is red dye harmful to hummingbirds? Dyes in food for human consumption have been controversial since the early 1900s. In the birding community, this has also been a hot topic for many years. While there are some strong opinions on either side, the short answer is, there is not enough definitive proof to say for sure one way or the other that red dye is harmful to hummingbirds. There have not been any scientific studies done directly on hummingbirds to investigate this. However, studies done on mice and rats have given evidence that at certain doses, red dye has harmful health effects.
Using red dye in nectar itself is really unnecessary these days, and I think the Audubon put it best when they said
“There’s no need for red dye here. Red coloring is not necessary and the chemicals could prove to be harmful to the birds.”
Why do some people add red dye to nectar?
So why is the red dye even there in the first place? Early bird watchers noticed that hummingbirds are very attracted to the color red. It is thought that hummingbirds use bright reds as one indicator in finding nectar producing flowers in the wild. So the idea was that by making the nectar red, it would stand out and attract hummingbirds to backyard feeders.
This made sense a long time ago when nectar feeders were mostly made from clear glass tubes and bottles. However today, most manufacturers of hummingbird feeders take advantage of this knowledge and feature the color red prominently on their feeders. The vast majority have red plastic/glass tops or bases. That is all that is needed to attract the hummers. Having the nectar also be red really ads no additional attractive value if your feeder already has the color red on it. Also, in nature, nectar is colorless.
- Check out our article how often to clean your hummingbird feeder
What is Red Dye #40?
The food and drug administration (FDA) banned Red Dye #2 in 1976 after studies showed links to cancer in rats. In 1990 Red Dye #3 was restricted, although not banned, for similar reasons. Since the 1980’s the red dye most commonly used in the United States is Red Dye #40, an azo dye made from coal tar. I looked up the most popular brands on Amazon that are selling red colored nectar and most listed Red Dye #40 as an ingredient.
Red Dye #40 goes by many names, most commonly Allura Red or FD&C Red 40. You’ll find it everywhere from candy to fruit drinks. Even today, it is still highly debated whether it causes negative health effects. Studies are currently being done to try and gauge potential affects of hyperactivity and behavioral issues in children. Nothing has yet been proven. The European Union and the FDA approve Red 40 as a food colorant, however several individual countries have banned it.