It is possible to get the whites of your eyes brighter, but you will have to consider several factors. The reddishness could very well be from eye strain caused by working on the computer. Make sure you rest your eyes often enough by taking frequent breaks from staring at the screen. Air-conditioned environments also makes the air very dry and can cause dry, red eyes. If you spend a lot of time in an air-conditioned environment you should either get a humidifier to put moisture in the air, or use lubricating eye drops. Make sure that you are getting sufficient sleep. Tiredness from insufficient sleep will also make your eyes reddish and dull. If your eyes are off-white to yellow you should pay attention to your liver. It may be a sign of a toxic, sluggish liver burdened by toxins. Do a good liver detox and minimize exposure to liver toxins such as alcohol, caffeine, sugar and saturated fat from animal origin.