It depends entirely on which enzyme and which problem. Lactase for lactose intolerance works, on a clear mechanism, and is the reason lactose free dairy exists at all. Pancreatic enzyme replacement for diagnosed pancreatic insufficiency is a prescribed treatment with strong evidence. Broad spectrum blends sold to healthy people for general bloating are a much weaker proposition: they are asking a capsule to do a job a healthy pancreas already does well. If a specific food is the problem, a targeted enzyme is worth trying. If the complaint is vague, the food diary will tell you more than the supplement will.

Some are and some are not, which is why this row grades borderline rather than clean. Pancreatin, pepsin, trypsin and ox bile come from animal pancreas or bile, typically porcine or bovine. Lactase, protease, amylase, lipase and cellulase are all available in microbial or fungal forms derived from Aspergillus or Bacillus cultures. A blend labelled only as digestive enzymes could be either. Look for the source organism on the ingredient panel, and be aware that plant derived options like bromelain and papain come from pineapple and papaya and carry their own allergen considerations.

Not as a general rule, and this is the assumption worth dismantling. Enzymes address a digestion problem, so they can help where the problem genuinely is a missing enzyme, which is lactose intolerance and, more narrowly, GOS in beans. They do nothing for a food allergy, which is an immune reaction to protein, and nothing for coeliac disease. They are also not a treatment for fructan or polyol malabsorption, because there is no human enzyme for those to replace. Using one as a shield to keep eating a food that reliably causes symptoms usually just delays finding the real trigger.