Question

What m&m color was discontinued in the 1970s

Answer 1

Answer: The red color

M&M's refers to an American trademark, called Mars (by Forrest Mars and R. Bruce Murriec, who purchased the rights of the formula to make the candy, hence the two Ms), which is a chocolate company that sells the famous chocolate dragees covered with a layer of sugar since the 1940s.

This sugary film came in different colors, keeping the same taste of chocolate, being the three original colors:

Red, yellow and green.

However, in 1972, because of the controversy generated with the finding of the toxicity of red dyes (especifically red dye #2 and #4) in the foods and cosmetics, and its relation with cancer that were generated at that time, the red color was discontinued.  

Even though this specific dye was not used in the elaboration of the sweet dragee (red dye #40 was used instead). All this in order to avoid confusion among consumers by misinterpretation of information, which would negatively influence the company's income statistics.

So, red was replaced by orange. However, in 1987 this color was reincorporated to the candies presentation.