Digestive enzymes: when lactase and alpha-galactosidase help, and when to see your GP

What digestive enzymes are

Enzymes are proteins that break food down into pieces small enough to absorb. Amylase handles starch, proteases handle protein, lipase handles fat and lactase handles milk sugar. Most of them come from your pancreas and small intestine.

Supplement enzymes come from three sources:

• microbes – fungal lactase, alpha-galactosidase, amylase and proteases;
• plants – bromelain from pineapple, papain from papaya;
• animals – pancreatin from animal pancreas, used in medicines.

An enzyme only helps with the food it breaks down. If your own enzymes are working, extra ones change little. So “enzymes for digestion” in general is a weak idea, while an enzyme matched to one food can make sense. For other gut supplements, see our gut health section.

Digestive enzymes benefits: what’s been studied

Lactase supplements: the one enzyme with an authorised claim

Lactase breaks down lactose, the sugar in milk. If you make too little, lactose reaches the large bowel and ferments. Usual symptoms, according to the NHS: tummy pain and rumbling, bloating, wind, diarrhoea or constipation and feeling sick. They start from a few minutes to a few hours after dairy.

In the UK and EU, lactase may carry this claim: it “improves lactose digestion in individuals who have difficulty digesting lactose”. Conditions of use:

• food supplements only, at 4,500 FCC units (Food Chemicals Codex) or more;
• taken with each meal that contains lactose;
• the pack must say that lactose tolerance varies.

The NHS agrees that a lactase supplement before food or drink containing lactose may reduce or prevent symptoms for some people. Live yoghurt cultures carry an authorised claim for lactose digestion too: more in our guide to probiotics.

For children, ask your GP or health visitor before using lactase, as the amount depends on age and diet.

How to tell if it’s lactose

Bloating after milk isn’t a diagnosis. The NHS suggests seeing a GP if symptoms keep coming back and often follow meals. Your GP may suggest:

• a lactose-free trial – cutting out dairy for a while to see if symptoms ease;
• a hydrogen breath test – it measures how well you digest lactose;
• blood tests, and a gastroscopy if symptoms are severe.

Lactose intolerance can also be a result of coeliac disease or inflammatory bowel disease. That’s why persistent symptoms get checked first, before you pick an enzyme. Once it’s confirmed, most people manage with smaller dairy portions or lactase for the trickier meals. The NHS advises against cutting foods out completely without advice from a GP or dietitian.

Alpha-galactosidase for wind after beans

Beans, lentils and cabbage contain sugars that humans can’t break down. Bacteria in the large bowel ferment them instead, and that’s where the wind comes from. Alpha-galactosidase breaks them down before the bacteria get the chance.

What the trials found:

• 1994, 19 people, a bean chilli. Wind was less frequent with the enzyme, but bloating and pain didn’t change.
• 2007, 8 volunteers, 420 g of beans. A dose of 1,200 GalU reduced hydrogen production and how bad the wind felt.
• 2016, 125 people with IBS, 12 weeks. The authors found no support for routine use. More people stopped taking the enzyme because of tummy pain and diarrhoea.

If beans and lentils are regulars on your plate, alpha-galactosidase is worth a try for wind. In IBS, there’s more evidence for soluble fibre such as psyllium husk, a low-FODMAP diet and probiotics. The enzyme only works at the meal, so take it with the first mouthful.

What’s inside an enzyme blend

Most tubs labelled Digestive Enzymes are blends: amylase, proteases, lipase, lactase, sometimes cellulase, bromelain and papain. It looks impressive, but there’s very little research on blends like these in healthy people.

If you want to try one, treat it as an experiment. Note what you ate and how you felt. If nothing changes after a couple of weeks, you don’t need it.

Bromelain and papain: pineapple and papaya enzymes

Bromelain is a group of protein-digesting enzymes from the stem and fruit of the pineapple plant. According to NCCIH, it’s been studied by mouth for sinusitis and after wisdom tooth removal, and the evidence is thin. As a topical product, it’s approved in the US and EU for removing dead tissue from severe burns.

People often take bromelain for digestion, but Memorial Sloan Kettering notes that studies are lacking. Papain from papaya has even less behind it: we found no reliable human trials for digestion.

What’s known about bromelain safety:

• the most common side effects are stomach upset and diarrhoea (NCCIH);
• allergic reactions have been reported (MSK);
• it may raise blood levels of tetracycline antibiotics;
• lab studies suggest it may raise the risk of bleeding, so don’t combine it with warfarin or other blood thinners;
• little is known about its safety in pregnancy or breastfeeding.

Pancreatin is a medicine, not a supplement

Pancreatic enzyme capsules (pancreatin) are medicines, used under a doctor’s care. They’re used when the pancreas doesn’t make enough enzymes, for example in chronic pancreatitis or cystic fibrosis.

The NHS lists signs that can point to a pancreas problem:

• very smelly poo that floats and is hard to flush away;
• feeling bloated or passing a lot of wind;
• losing weight without trying;
• feeling thirsty or needing to pee a lot.

These need a GP appointment and tests. Your doctor sets the pancreatin dose. Supplement enzymes from iHerb aren’t a substitute, even if they contain lipase.

When to see a GP about digestion

Heartburn, fullness and burping after meals are usually down to stomach acid, not missing enzymes. For heartburn, the NHS suggests asking a pharmacist about antacids or alginates. But some signs need a GP:

• you keep getting indigestion or it’s very painful;
• you’ve lost a lot of weight without meaning to;
• you have difficulty swallowing or keep being sick;
• you have iron deficiency anaemia;
• you notice blood in your vomit or poo;
• you can feel a lump in your stomach;
• changes in your poo, bloating or discomfort last 3 weeks or more.

Before you buy, run through this quick check:

Who should avoid digestive enzymes

• Blood thinners (warfarin and others): avoid bromelain.
• Tetracycline antibiotics: bromelain may raise their levels.
• Allergy: allergic reactions to bromelain have been reported. If you’re allergic to pineapple or papaya, avoid enzymes made from them.
• Pregnancy and breastfeeding: there’s little safety data for bromelain or blends, so ask your midwife or GP.
• Pancreatic disease or cystic fibrosis: only the pancreatin your doctor prescribes.
• Children: any enzyme only after talking to your GP or pharmacist.

To check combinations with other supplements, see our vitamin compatibility chart.

How to choose digestive enzymes on iHerb

1. Start with which food sets off your symptoms. Dairy points to lactase, beans to alpha-galactosidase.
2. Look at activity units, not milligrams: FCC for lactase, GalU for alpha-galactosidase.
3. For lactase, choose at least 4,500 FCC per meal.
4. In blends, check for bromelain or papain if you take blood thinners.
5. If nothing improves in a couple of weeks, stop and see your GP.

Our label-reading guide shows where to find activity units on a Supplement Facts panel. Not sure what you need? Start with our vitamin check.