Stop me if you’ve heard this one before. Somebody (usually on the internet) told you that in order to improve your digestive health you need to buy (also usually from the internet) some digestive enzymes to improve your body’s efficiency at metabolizing food. The benefits, although usually left somewhat vague, generally involve weight loss, more vitality, and a generalized sense of well-being.
But will digestive enzymes actually help you lose weight? Actually, no they won’t. If you think about how digestion works, it is easy to see why they are more likely to do the exact opposite.
Until the early 19th Century, the process of digestion was poorly understood. It was generally assumed that the stomach would in some way grind up the food into small pieces that would then be absorbed into the body. What role gastric juices played in the whole process was somewhat unclear.
That changed in large part thanks to William Beaumont, whose work as a US Army surgeon brought him into contact with Alexis St. Martin, a Canadian voyageur who had the misfortune to be accidentally shot in the stomach, and the good fortune to survive the experience. St. Martin’s injury eventually healed but left him with a fistula; a hole in his stomach that connected to the outside world. Beaumont, realizing the opportunity, used St. Martin for a series of experiments. He was able to introduce food tied to a piece of string directly into St. Martin’s stomach and then remove it periodically to see how food was actually digested in a living human. He also took samples of the gastric juices from St. Martin’s stomach and applied it to bits of food in his lab. When the food dissolved, Beaumont showed that food was broken down through the chemical action of these digestive juices, not the churning of the stomach.
The somewhat dubious ethics of Beaumont’s experiments notwithstanding, his experiments did advance the understanding of human digestion. We now know that the pancreas produces the digestive enzymes used by our body to break down food and it is a combination of these enzymes that are generally sold in stores and over the Internet to aid in digestion. On the surface, this seems like a reasonable thing to do, but if we look at how pancreatic enzymes are used clinically, we can see an obvious problem with this course of action.
Patients with chronic pancreatitis can develop an enzyme deficiency. Unlike acute pancreatitis, which is a sudden, very painful but temporary problem, chronic pancreatitis occurs over a long period of time and generally results in permanent damage to the pancreas. However, the pancreas is a remarkably resilient organ and over 90% of it has to be damage before its enzyme producing capacity is impaired. Nevertheless, patients with chronic pancreatitis and a digestive enzyme deficiency can develop malnutrition because they are unable to break down their food to be absorbed by the intestines.
These patients often suffer from abdominal pain, usually brought on after eating. Since they do not digest their food properly, they also have loose foul-smelling stools, which contain their undigested food matter. Consequently, they become malnourished and lose weight.
There is no real way to reverse the damage with chronic pancreatitis, although abstaining from alcohol and cigarettes helps somewhat, as does avoiding large meals. This is one situation where pancreatic enzymes would be used clinically and prescription formulations contain some combination of lipase, amylase, and protease (the enzymes to break down fat, carbs, and proteins respectively).Importantly, these formulations are enteric-coated tablets to protect them as they pass through the stomach, since the very concentrated acid in the stomach can inactivate uncoated enzymes. Uncoated formulations are sometimes used clinically but they have to be combined with acid suppressing medication to maximize their effectiveness.
Many patients do improve with pancreatic enzyme replacement. However, remember that these patients were often malnourished due to the fact that they were not properly absorbing their food, and success is defined by whether they start to regain their weight.
Thus, the consequence of pancreatic enzyme replacement is weight gain, not weight loss, which I do not think most people understand when they buy the product. While many people suffer from some gastrointestinal complaint, it is rather unlikely that you have chronic pancreatitis and would benefit from pancreatic enzyme replacement. Most cases of bloating and gas are caused by too much swallowed air and could be treated by people chewing their food more thoroughly. Thus it would probably be best if people did not start treating themselves before confirming that they actually have a disease. So just as one would not start taking insulin until a diagnosis of diabetes is made, it is probably best not to start taking pancreatic enzyme supplements until their need has been confirmed.