A Ministry of Consumer Affairs survey has found that a number of baby bottles sold here have incorrect volume markings.
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Of 35 bottles tested, 15 had volume markings that were inaccurate by more than 5 percent.
Eleven bottles overestimated the volume of liquid by up to 40 percent – which means the formula in the bottle will be over-concentrated.
Formula that’s too concentrated can cause vomiting, diarrhoea and constipation. Over time, the excess energy and nutrients provided could harm the development of important organs such as the kidneys. This is a particular risk for babies aged six months or younger who depend on formula for all their food and fluid needs.
Four bottles underestimated the volume of liquid by 6 to 10 percent. Using these bottles would result in over-dilution of the formula – and babies who are fed formula with too much added water may not get enough energy and nutrients.
The inaccurate bottles tended to be cheaper unnamed brands bought from discount shops. The European standard EN 14350 requires that bottles filled to 100ml are accurate within 5 percent. Bottles that state on the packaging that they comply with this standard or have EN 14350 stamped on them should be accurate.
Tip: Your local pharmacy can check the accuracy of your baby bottles – but ask whether there’s likely to be a charge for this.