When i do a basic edit in Photoscape to my .jpg images the file size doubles, Why is this?

I%26#039;m and just going through my pics and doing a auto adjustment to them. I%26#039;ve noticed that the file size is going from like 1.5 to 3.5. Why is this happening? I%26#039;m not changing file types or anything.|||You%26#039;re probably saving it at a higher quality level.