How can I recover to original image after i changed to gray level ?

Img=imread('image1.jpg');
Gray=rgb2gray(img);

How convert Gray to original color now????

Answer 1

[Image Analyst]

Very simple in fact trivial:

Gray = Img;

[Alhanouf Alshahrani]

Thank you , it's working with me

Answer 2

[Walter Roberson]

If you are using uint8 RGB, then there are 256^3 different RGB combinations and they must map to 256 values. On average, each gray level must correspond to 256^2 = 65536 different RGB combinations. So given only the gray level, how can you possibly know which of the 65536 it "really" is?