I spend my workdays talking with people who suffer a wide array of digestive problems. Many have been in distress for quite some time. It’s pretty common for people on a journey for “inner peace” to experiment with dietary supplements along the way, often based on internet research, recommendations from alternative health practitioners or testimonials from others for whom the supplement has worked wonders.
Products marketed as digestive enzymes are particularly popular in the digestively-disturbed crowd, and my patients often ask me whether these products are something I recommend.
What Is a Digestive Enzyme?
I think it helps to first understand what an enzyme actually is: a protein that facilitates a particular chemical reaction. In the case of human digestion, our bodies produce a wide range of different enzymes to facilitate the chemical breakdown of different food components into their smaller, absorbable building blocks.
An important thing to know about enzymes is that each one is specific to a particular type of biochemical reaction. In other words, a protein-digesting enzyme — called a protease — cannot break down things that aren’t proteins, like carbohydrates, fats, sugars or fiber. And even within the family of protein-digesting enzymes our bodies produce, different ones are required to attack the chemical bonds at different locations and configurations within a protein’s chain.
Without getting too mired down in biochemistry, these characteristics of enzymes highlight an important point:
An enzyme will only help improve digestion of a food if it’s the right type of enzyme for the right type of food.
Relatedly, digestive enzymes will also only help improve digestive symptoms if those symptoms are indeed related to maldigestion of particular nutrients.
One of the issues I help patients understand is whether poor digestion of certain foods is indeed the cause of their bloating, gas, diarrhea or general digestive distress. And if it is, are there are enzyme supplements available that target the poorly-digested nutrients effectively to help alleviate symptoms? After all, if your problem is poor digestion of a fiber found in beans called oligo-saccharides, then taking a fat-digesting enzyme isn’t going to help you. And so on.
The Most Common Maldigested Nutrients
The most commonly maldigested nutrients that can cause adverse gastrointestinal symptoms include:
— Lactose is a natural sugar found in milk and other dairy products. When people do not manufacture enough lactase enzyme in their small intestines, lactose cannot be absorbed properly in the gut, leading to gas, bloating and diarrhea several hours later. Taking supplemental lactase enzyme with the first bite of dairy foods can help prevent this.
— Fructose is a sugar found in certain fruits and sweeteners — from honey and agave to high fructose corn syrup. Sodas, juices, soft drinks and candy can be particularly concentrated sources of fructose. When people lack enough receptors in their small intestines to absorb fructose adequately, it leads to gas, bloating and diarrhea several hours later. Taking supplemental xylose isomerase enzyme (also known as glucose isomerase) just before eating fructose-containing foods can help prevent this. The enzyme converts fructose to glucose, a different type of sugar that’s easily absorbed through a different pathway.
— Fructans is a type of carbohydrate found in onions, garlic, artichokes, jicama, wheat, barley, rye and a type of fiber called inulin (or chicory root fiber), which is often added to bars, low-carb foods, “healthy” ice creams and a variety of processed foods. Fructans are also marketed as “prebiotic fiber” and sold as gut health supplements. Human beings do not have enzymes to break down this particular carbohydrate — essentially a chain of linked fructose molecules — and sensitive individuals may find it to produce uncomfortable gas pain and bloating several hours after consuming it. Unfortunately, there are no commercially available enzyme supplements that are effective digestive aids for fructan-containing foods.
— Sucrose, also known as white sugar or just plain sugar. While sucrose intolerance — caused by deficiency of the enzyme that breaks down sucrose into its absorbable component parts — is not nearly as common as lactose intolerance or even fructose intolerance, it’s also not as rare as previously believed. The symptoms of sucrose intolerance mimic those of lactose/fructose intolerance and will onset several hours after consuming certain fruits, vegetables, juices, sweetened foods and beverages. A supplemental enzyme called sacrosidase is available by prescription only for people diagnosed with sucrose intolerance via breath testing or intestinal biopsy.
— Galacto-oligosaccharides are complex carbohydrates found in certain plant-based foods — like Brussels sprouts, chickpeas, beans, peas, beets and cashews — that give these healthy foods that give these healthy foods their gassy reputations. Humans don’t make the enzyme required to digest these microbiome-feeding fibers, but certain species of fungi do. Alpha-galactosidase enzyme, derived from a type of mold, is available as a dietary supplement (such as Beano) and has been demonstrated in controlled studies to significantly reduce the intestinal gas associated with bean intake.
— Fat is primarily digested via lipase enzyme, which is manufactured in your pancreas. But in cases where the pancreas does not produce or secrete enough lipase, incomplete digestion and the resulting malabsorption of fat results in symptoms like floating, orangey or oily stools, diarrhea, malodorous gas, and/or unintentional weight loss. One such cause of this is a condition called pancreatic insufficiency, which is diagnosed via stool testing. While over-the-counter digestive enzyme supplements do typically include lipase among their ingredients, the doses are not typically sufficient (or standardized) to effectively treat pancreatic insufficiency. If you’ve been diagnosed with pancreatic insufficiency, prescription pancreatic enzyme replacements are advisable to ensure the adequate dose of needed enzymes are delivered to the intestine in a properly-coated, protective capsule.
You may encounter a variety of other ingredients in supplements marketed as digestive enzymes, though most of them are not likely to be helpful as digestive aids. This is because they are redundant to your body’s own very unlikely-to-be-impaired production, or because the food compounds they purport to digest don’t generally cause gas and bloating to begin with.
Some ingredients, like betaine HCl, bromelain (derived from pineapples) and papain (derived from papayas), are commonly included in products marketed as dietary supplements. None of them have ever been studied in human beings to determine what effect, if any, they may have on digestion. Any marketing claims that they aid in either nutrient breakdown or digestive system motility are therefore based on speculation, not actual evidence.
For Those With Gluten Problems
Lastly, you may encounter a digestive supplement marketed as a “gluten degrading enzyme,” sometimes nicknamed “glutenase.” It’s typically targeted at people with celiac disease or suspected wheat/gluten intolerance who need to eat a gluten-free diet. Because there is no actual human digestive enzyme called “glutenase,” these products are not mimicking or replacing a deficient enzyme in the human body.
They may contain one of several ingredients selected by their manufacturers. The most common such ingredient in these products is dipeptidyl peptidase IV, or DPP IV. Of note, DPP IV has barely even been studied in humans, and the available data suggest that it does not degrade gluten substantially enough — and in some studies, even at all — to render it safe for people with celiac disease.
Because these dietary supplements are also unregulated, there is a risk that they could contain undeclared wheat ingredients, as so many other dietary supplements have been found to. Any dietary supplement marketed as a gluten-digesting enzyme does not make gluten consumption safe for people with celiac disease and should be avoided.
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