Huge variation in price of vitamins
Effervescent vitamin C tablets are the country's best selling supplement - but consumers are paying widely varying amounts for similar products.
Comparable vitamin bombs can cost five times as much as others.
The Irish Independent priced five high-strength 1000mg vitamin C tablets and found that a tube of 20 varies in price from €1.09 for Tesco's own-brand to €4.99 for Seven Seas Haliborange at Boots.
That means a single tablet costs 5c at Tesco compared with 25c at Boots.
Kelkin's tablets cost €4.59 at Murray's Pharmacy in Dublin 1, while Boots own-brand tablets cost €3.49 and Holland & Barrett retailed at €3.55.
Nielsen figures show we spent over €4m on these types of vitamin tablets in the last 12 months, nearly a quarter of the €13m we forked out for all vitamins in supermarkets. The figures don't include health store and pharmacy sales.
Berocca is the best-known of these vitamin tablets - but we didn't include it in the price survey because its products are multivitamins rather than pure vitamin C.
The prices of some other multivitamin tablets also varied widely - Seven Seas Multibionta multivitamin (30) cost €7.49 at Boots, which was 44pc more expensive than Dunnes Stores where it cost €5.19.
Asked about its high prices, Boots said it gives great value on vitamins through its '3 for 2' offer and through loyalty card points on purchases.
Kelkin said its tablets were produced with a full-time dietitian to advise on standards while Tesco would have vastly greater economies of scale.
Nielsen analyst Ruth Lloyd-Evans said that vitamin sales in grocery stores had declined by 3pc, which was probably due to shoppers switching to pharmacies to buy them.
Sales of children's vitamins are outpacing adult ones, though they still account for only 6pc of the market. Sales of vitamins for women, such as for pregnancy and menopause, are also growing.