Taste test

Kefir is a traditional fermented milk drink that’s been found to boost good gut bacteria — you’ll find it in health food stores, Eastern European shops and some supermarkets. Non-dairy versions are also available; we tried both. You can easily make your own if you get your hands on some kefir grains.

Rhythm Pure Coconut Kefir, 500ml, €7.10, 10/10

This Dutch kefir is made from cold-pressed coconut milk and live kefir cultures — it’s fizzy and delicious. Our testers loved it. Suitable for vegans.

Blakes Feel Good Organic Natural Kefir, 250ml, €2.10, 9/10 Sharp-tasting without being unpleasant, smooth, organic, and made in Drumshambo, Co Leitrim. Contains just organic milk and bacterial cultures.

Biona Organic Kefir, 250g, €2.65, 8/10 Funkier-tasting than any of the other kefirs that we tested

— and the most like home-made. Novices may find the strong flavour off-putting. This one divided our testers — it’s not for the faint-hearted.

KefZing, Coconut Milk Kefir, 125ml, €2.50, 7/10 This kefir is suitable for vegans, and made in Ireland using just three ingredients: coconut extract, water and kefir cultures. The coconut flavour is not overpowering and the size is ideal for a quick pick-me-up. Tasty but pricey.

Danone Kefir, 200g,

85c, 7/10 This tangy kefir comes from Poland and contains just milk, active bacteria cultures and kefir yeast cultures. It’s very well-priced.

Milko Natural Kefir, 330ml, 80c, 7/10 This Polish-made kefir contains just milk and live cultures of kefir bacteria. It’s tangy and cheap.

Žemaitijos, Pina Colada Kefir Cocktail, 450g, €1.25, 3/10 This kefir is from Lithuania — our testers found it tooth-shatteringly sweet. The coconut and pineapple flavours are pronounced and it contains 9.6g of sugar per 100g. The list of ingredients is long.