FAST FOOD fans have been left amazed after only just realising why their favourite chains have red & yellow logos.
The pattern was noticed by a Reddit user who observed that a large number of burger and fried chicken restaurants include the same colours in their logos.
The user queried: "Why do fast-food restaurants share the same colour schemes - red, yellow and white?
"I was doing a marathon drive last night and realised that many fast-food companies share the same colour combinations with their logos.
"Why is this? In N Out, McDonald's Carls Jr, Burger King, Wendys, KFC."
Psychologist and leading colour expert Karen Haller stepped in to explain the deliberate marketing ploy behind the eye-catching colours.
read more in fabulous
Posting on her official behavioural consultancy website, Karen revealed the "combination of colours emits is perfect for their target market".
She continued: "Looking at the positive psychology qualities of red and yellow in relation to the fast food industry, red triggers stimulation, appetite, hunger, it attracts attention.
"Yellow triggers the feelings of happiness and friendliness.
"When you combine red and yellow it's about speed, quickness.
Most read in Fabulous
"In, eat and out again."
Colours, Karen continued, are a far more efficient way to lure in famished customers.
She said: "Yellow is also the most visible colour in daylight, which is why the McDonald's M can be seen from a far distance.
"The language of colour is communicated quicker to the brain than words or shapes as they work directly on our feelings and emotions."
The discovery inspired shock across social media.
One user said: "No joke, it makes me crave fries and ketchup.
"When I get there, I figure I might as well get a McDouble and chicken sandwich to wash it all down."
A second chimed in: "You learn something new every day."