It’s quite well documented the red and yellow used in conjunction can cause people to feel hungry.
Are there any other well known colours or combinations that used in a certain context evoke a similar such psychological influence on peoples behavior, deeper than the surface level attributes of a colour i.e. Blue: calm, competence, security…?
Except… KFC has no yellow in it?
Red is a universal colour for “stop” in most countries and civilisation. Yellow is mostly connected with feeling happy.
Other logos like Netflix and H&M use red in their logos.
But Subway use Green and Yellow. Probably because Green be a go/eco colour and green being good for ready to go - on the move etc.
I’ve read that before, but I’m skeptical. I’d need a good, scientific study backing it up before I’ll accept it as fact. Red and yellow don’t make me hungry — the signs just stand out more on a crowded street.
I don’t eat much fast food, but tonight I stopped by the drive-up window at Wendys — $35. Geech! A decent sit-down restaurant only costs about that much.
I’m still trying to figure out when Pizza went to over $20!
I make my own pizza using yoghurt and flour to make the dough, and then sprinkle anything you like on top - mostly veg/chicken etc. to keep cals down. Costs about £0.50 a pizza.
The mark-up on pizza is crazy. Making hand over-fist.
I used to help out a friend of mine running their own food kiosk. Coffee and Tea for £3 - it only cost £0.10 to make it.
And his other big seller was hotdogs - £5 a hotdog, and it only cost £0.20 to make one.
His brother and himself set it up as a weekend gig, they were qualified electricians and had really good paying jobs. Now they both sell tea/coffee/hotdogs on a full-time basis and make much more than they were earning in their trade.
If I had a craving for KFC, my thoughts would be “Hmm, grease and salt …”, and not “Hmm, it has red and black on its logo. I want it!”.
If I shopped at IKEA, it’s most certainly not because blue and yellow are good colours.
I usually make my own pizza too. That’s why $20 was a surprise! Last time I bought it, I think it was more like $10. Which reminds me I need a new sourdough starter. Mine turned on me. And she was 5 years old too and made the best-tasting pizza dough. Kept her in a glass “brain jar” in the fridge. Her name was Abbie…something… 
Ahh you’re right. Am not able to find a scientific study which supports it. I guess I thought it was something that had a more scientific basis, because these massive multinational corporations had elected this colour scheme and I assumed that the would have done so with a very considered reason why. 
Well, that’s exactly what colour psychology is, you are being influenced by colours.
There’s 2 airlines I use, one has the blue and yellow theme, and the website looks a bit tacky - but it’s designed to look cheap so the end user feels like they’re getting a deal.
The other website I use for flights uses a green and white spacious theme, and looks a little bit more salubrious.
But compare the flight prices and they are roughly the same for similar travel destinations.
There is some substance to it - but I wouldn’t put all my stock in it.
The thing also with color theory is that not all colors mean the same thing in all cultures.
Know your audience.
If people are using red and yellow to induce hunger, they may want to rethink that. Red and Yellow is McDonalds, the association has been there so long you wonder if the tail is wagging that dog, and McDonalds is about the last place on my list of places to go to eat, ranking right down there with gas station roller food (which I’ve never eaten.)