Pineapple juice provides nutrients in the diet that are important for the body's biological processes, including digestion. The danger of too much of any food is that sometimes it can cause unpleasant reactions. In the case of pineapple juice, sometimes it may cause unwanted digestive effects, depending on the sensitivities of those drinking it.
A protein-digesting enzyme called "bromelain," found in pineapple juice, breaks down protein in the digestive tract, which speeds nutrient absorption, the creation of waste and elimination, according to the University of Maryland Medical Center. If you drink more than a few servings of pineapple juice, the bromelain may react more quickly with the foods in your digestive tract.
A cup of pineapple juice provides 25 grams of simple sugars, a significant amount. Juicing a pineapple removes fiber, a nutrient that ordinarily slows the entry of sugar in the bloodstream. If sugar assimilates quickly, it may cause your blood sugar to increase unhealthily and the stomach and intestines may become irritated. If you have a sensitive stomach, limit intake of pineapple juice to avoid gastric discomfort.
The composition of pineapple juice contains primarily water in addition to the nutrients it provides. Water stimulates bowel movements because it hydrates the colon and prevents constipation. Drinking juice, water and other fluids is important for keeping the water balance in the colon conducive to frequent, healthy elimination.
Points to Consider
Aside from possible digestive upset there are other points to consider when drinking pineapple juice. Drinking juice instead of consuming the whole fruit increases your risk for developing diabetes, according to a report from Harvard University published in the "Harvard Gazette." This information confirms a 2008 study published in the July 2008 issue of "Diabetes Care," which states that the risk may be particularly higher for women. Whole fruit such as pineapple contains fiber, which makes it pass more slowly through the digestive tract than juice does. A slower digestion means a slower rate of sugar absorption.