A box of formula on the supermarket shelf comes with a barrage of warnings. The packaging describes its contents as a “breastmilk substitute” and cautions that “failure to follow instructions may make your baby ill”. Yet nobody warns parents about the risks of breastfeeding. And they should.

New data suggests that breastfeeding may be driving skyrocketing newborn hospital readmissions. Figures uncovered by BBC File On 4 Investigates show that last year around 30,000 babies under two weeks old were readmitted to hospital with jaundice. Feeding difficulties were recorded in nearly 10,000 of these babies, while over 5,000 had abnormal weight loss. Infant feeding charity Feed UK has found a 60% increase in newborn emergency hospital readmissions. Inadequate milk intake can contribute to neonatal jaundice, dehydration and hypoglycaemia, require hospital treatment and, in severe cases, cause permanent injury or even death. So, what is driving the increase in feeding-related newborn hospital admissions? And what should be done about it?

Healthcare professionals have improved their screening for jaundice, but that alone seems unlikely to account for the steep rise. Another explanation is that women are having children later in life and more are having assisted births, which can make breastfeeding trickier. Rates of exclusive breastfeeding appear to be increasing, too: UK infant feeding surveys show that a higher proportion of mothers now initiate breastfeeding and continue to breastfeed exclusively one week after birth.

While correlation does not prove causation, breastfeeding seems likely to be driving the increase in infant readmissions. This may be happening alongside other factors, such as older maternal age and more assisted deliveries, or because more women are attempting to breastfeed exclusively.

Really, they should be warned that exclusive breastfeeding carries risks. They should be informed about the signs of underfeeding, the importance of early supplementation with formula, the need to seek emergency support, and what can happen if they delay giving formula or getting medical help. They should be given all of this information proactively, up front and in full.

Yet current NHS policy prevents this from happening, because the UK’s infant feeding policy is resolutely committed to promoting exclusive breastfeeding. Public health bodies only monitor data on breastfeeding rates, and National Institute for Health and Care Excellence (NICE) guidelines prevent proactive information about formula. NHS maternity services must be accredited by the Unicef Baby Friendly Initiative, a programme that claims to support informed choices in infant feeding, but which actually promotes exclusive breastfeeding for the first six months. Healthcare professionals are told that they must never imply “breastfeeding and formula feeding are an equal choice.”

The result is that pregnant women and new mothers receive selective and distorted information. The benefits of breastfeeding are exaggerated and its risks ignored, while formula milk is demonised. Consider the misinformation surrounding the prevalence of insufficient breastmilk production. The NHS tells pregnant women it’s “very rare” not to produce enough milk. But lactation researcher Donna Geddes found in one study last year that 38% of women have low milk supply. According to the latest national Infant Feeding Survey, 44% of women who stopped breastfeeding did so because they did not have enough milk. These are staggeringly high percentages, not “very rare”.

New mothers often try everything to increase their milk supply: breastfeeding on demand, pumping after every feed, eating lactation cookies, securing prescriptions. Many see it as their fault, but it seems likelier that a much larger proportion of women than the NHS admits cannot actually produce enough breastmilk to feed their babies exclusively.

Britain’s infant feeding policies need urgent scrutiny and fundamental change. Current policy is at best reckless and at worst dangerous, harming mothers and babies alike. This week’s headline-grabbing numbers of newborn admissions should prompt an overdue wake-up call.