There aren`t any studies that say it does hurt them but there are also no studies that say it doesn`t hurt them. Because these little birds ingest so much nectar in the course of a day, any additives to the nectar could have a cumulative effect. Given that most hummingbird feeders have enough red on them to attract the birds it`s actually less hassle to forgo the additives and just stick with straight cane sugar and water.

One thing is for sure it is unnecessary. A true waste of money hummers will come to your feeders without using the red coloring so why take the chance of hurting these adorable creatures.

Thanks. I have plenty of hummers visiting my feeders through out the day. I worry that they visit feeders that have harmful additives. At least they have fresh homemade nectar from me.

There's an entire snopes article on the idea that red dye hurts hummingbirds. It doesn't.

It's not necessary, but its not a problem either.

Sorry to double post, but I saw a comment about "unhealthy additives".

The only additives in most commercial hummingbird food are electrolytes, and anti-fungals. Fungi can be a huge issue with hummingbirds, so if you're not cleaning your feeders very regularly (or your neighbor isn't), telling them to use home made stuff is putting the birds in danger.