Lactase

Lactase is a digestive enzyme. It splits lactose, the sugar in milk, into two smaller sugars: glucose and galactose. Babies make plenty of it. In many adults production falls away, so lactose travels on to the large intestine, where bacteria ferment it. That is where bloating and wind usually come from.

A supplement works on the meal in front of you, not on your own enzyme production. Lactase enzyme improves lactose digestion in individuals who have difficulty digesting lactose. In the EU that claim may be used from 4500 FCC units per lactose-containing meal. Lactase sits with the other digestive enzymes we carry, and it has the narrowest, clearest job of them all.

Read the FCC units, not the milligrams

FCC units measure enzyme activity. Milligrams only measure weight, so two 200 mg tablets can differ a lot in what they actually do. Check the units per serving, then check how many tablets one serving is. A product listing 4500 FCC per two tablets costs twice as much per meal as it first appears.

Then match the strength to your plate. A splash of milk in tea asks less of the enzyme than a cheese fondue or a large ice cream. Many people keep two strengths at home: a low one for everyday coffee and a higher one for eating out.

The forms differ in timing, not in the enzyme

Tablets and capsules are taken with the first bite. Chewables are easier away from home and for people who dislike swallowing pills. Drops are stirred into milk and left in the fridge, so the lactose is already broken down before you drink it. Acid stability also matters, because an enzyme destroyed early in the stomach cannot help further down. Three practical points that come up often when people ask about everyday digestion:

• Lactase does not need to build up. It works meal by meal.
• Heat damages the enzyme, so do not stir it into hot food or drinks.
• The lactase used in supplements is made by fermentation, not from milk, so most products are dairy free and suitable for vegans.

How we choose the lactase we stock

We judge lactase on three things: the enzyme activity per serving, whether that activity survives stomach acid, and whether the format fits the moment you actually eat. We state FCC units per serving so you can compare products directly instead of guessing from milligrams. We prefer acid-stable forms, and we keep both low and high strengths so you are not paying for 9000 units to cover a milky coffee. We are brand-neutral and buy directly from the brands. Every product passes our compliance team, and independent labs spot-check batches. Read how we select our brands.

Lactase suits you if you want dairy to fit into a normal day, at a restaurant or a birthday, without planning around it. It is fair to say what it does not do. It has no effect on a cow's milk protein allergy, which involves the protein and not the sugar. It also will not help if your discomfort comes from something other than lactose. If symptoms continue, your GP can look at the cause. Some people also use live bacteria cultures for day-to-day gut comfort, alongside lactase for the meals that need it.