Tuna or ripe fruit of the prickly pear cactus has been used as a folk remedy and a food source for many generations of Jamaicans and other cultures around the world. The tuna is eaten raw and made into jams, jellies and beverages such as juice and herbal teas. Tuna usually refers to the oval red fruit that is produced by the cactus. Both the fruit and the leaves of the prickly pear cactus are used as herbal remedies in Jamaica and many other countries.
The flesh of the cactus leaves are sometimes applied directly to minor cuts, burns and musculoskeletal injuries to stimulate healing and reduce pain, which is similar to how the aloe vera plant is used. Furthermore, the fresh sap from the cactus leaves is used as a natural cleaning shampoo and to eliminate dandruff and other scalp problems. The prickly pear fruit (known as tuna in Spanish) is a rich source of the mineral magnesium and the amino acid taurine, nutrients often cited as important to brain and heart health, and is also rich in flavonoids, antioxidants credited with keeping arteries healthy.
A cactus pear weighs 103 grams, or 4 ounces, and contains 42 calories. You will gain weight if you eat more calories than you expend, and emphasizing low-calorie foods in your diet can help you limit your calorie intake and control your weight. Cactus fruits are good for preventing weight gain or losing weight because 88 percent of their weight is from water. Water is a calorie-free nutrient that suppresses hunger to help you feel full.
It is also touted for its antiviral and anti-inflammatory properties. Some preliminary evidence shows that prickly pear cactus can decrease blood sugar levels in people with type 2 diabetes. Research also suggests that prickly pear cactus extract may lessen the unpleasant effects of a hangover. However, more research is needed to confirm these benefits. Allergy to cactus is quite rare; however, individuals with known allergy to cactus should avoid using them entirely.