Lime juice has a range of beneficial uses in aiding digestion, relieving constipation and respiratory disorders, improving the complexion, healing wounds and ulcers, alleviating the pain of arthritis, protecting eyes, reducing fever, detoxifying the body and losing weight. In the past, it has been used for combating scurvy by the military because its high vitamin C content prevents deficiency symptoms like cracked lips and bleeding gums.
Lime juice aids in digestion in two ways: First, by causing salivation in the mouth and second, by breaking down food molecules with its natural citric acidity. This acidity is also why lime juice is useful for relieving constipation, since it is capable of cleansing the excretory system. High quantities of lime juice with salt can also be used as a purgative.
Respiratory disorders benefit from the flavonoids in lime (which can be released simply by scratching lime zest and inhaling the vapors). In fact, flavonoids are used widely in commercially-available decongestants.
Lime juice is also beneficial for the skin. Combining the vitamin C in the juice with the flavonoids in the peel results in a powerful antibiotic and disinfectant agent, useful for clearing the pores, preventing dandruff and soothing rashes and bruises. It is useful for eye care for much the same reasons.