drinking enough water.
pregnancy
photosyntosis
Urine is yellow due to the presence of a pigment called urobilin. When urine is dilute,its colour becomes light due to the abundance of water. Dark yellow urine shows that the urine is concentrated which is because of dehydration.
Some vitamins and some soft rinks can cause urine to be yellow. The B vitamins often cause urine to be very yellow.
This is generally a light yellow color.
Why is my urine very light yellow almost clear in color and has an odor and is foamy?
Not drinking enough wter
The color of the urine is based on how much you drink, not whether you are pregnant or not. You can not tell that by looking at your urine.
Normal urine colors can vary from pale yellow to dark amber, depending on hydration levels.
Cat urine contains a substance called phosphorus, which glows under ultraviolet light, such as a black-light. This causes the urine to appear fluorescent or glowing when exposed to a black-light.
nice video on the yellow light . http://www.youtube.com/watch?v=zn89z_VUcP0
The color of urine depends on type of diet alone and not skin color or race. Normal urine color ranges from light yellow to dark yellow.