What water to use for baby formula
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Optimal Water for Baby Formula Preparation
Risks of Using Tap Water for Baby Formula
Microbiological and Chemical Hazards in Tap Water
Using tap water to prepare infant formula can pose significant risks due to potential contamination by microbiological and chemical hazards. In France, a study highlighted the dangers of Cryptosporidium and arsenic in tap water. Cryptosporidium can cause severe diarrhea, leading to a high number of Disability Adjusted Life Years (DALYs) lost, while arsenic exposure can increase the risk of lung and bladder cancer later in life. Boiling tap water can eliminate the risk from Cryptosporidium but does not remove arsenic, which remains a concern for a small percentage of the population exposed to high levels1.
Nitrate Contamination in Well Water
Well water, often used in rural areas, can be contaminated with nitrates, leading to methemoglobinemia or "blue baby syndrome." This condition can cause serious health issues, including coma and death, if not treated promptly. Cases have been reported where infants developed this condition after consuming formula made with nitrate-contaminated well water2.
Recommendations for Safe Water Use
Boiling Water to Eliminate Bacteria
The World Health Organization (WHO) and the UK National Health Service (NHS) recommend using water heated to at least 70°C to prepare powdered infant formula (PIF). This temperature is sufficient to kill harmful bacteria such as Cronobacter species, which can cause severe infections in infants. Studies have shown that many PIF preparation machines do not heat water to the recommended temperature, posing a risk of bacterial contamination. Therefore, using a kettle to boil water is a safer option3 5.
Bottled Water as an Alternative
Contrary to some healthcare professionals' advice, bottled water can be a safe alternative for preparing infant formula, especially when tap water quality is compromised. A review of bottled water's chemical quality found it generally suitable for infant formula preparation. However, it is crucial to ensure that the bottled water used has low mineral content and is free from contaminants4.
Special Considerations
Avoiding Supplemental Water for Breastfed Infants
For exclusively breastfed infants, supplemental water is generally unnecessary, even in hot climates. Studies have shown that breastmilk alone is sufficient to maintain hydration and water homeostasis in infants, and introducing supplemental water can reduce breastmilk intake, which is not advisable7.
Conclusion
When preparing infant formula, it is essential to use safe water to avoid health risks. Boiling tap water to at least 70°C is recommended to eliminate bacterial contamination. Bottled water can be a safe alternative if it meets safety standards. For exclusively breastfed infants, supplemental water is not needed, as breastmilk provides adequate hydration. Ensuring the safety of the water used in infant formula preparation is crucial for the health and well-being of infants.
Sources and full results
Most relevant research papers on this topic
Development of a Cryptosporidium-arsenic multi-risk assessment model for infant formula prepared with tap water in France.
Using un-boiled tap water for infant formula preparation in France increases the risk of Cryptosporidium diarrhea and arsenic exposure, with a 5% risk of elevated cancer risk.
Blue babies and nitrate-contaminated well water.
Nitrate-contaminated well water can cause blue baby syndrome in infants, with potential for coma and death if not treated appropriately.
Case Report
Rigorous Journal
Highly CitedThe safety of at home powdered infant formula preparation: A community science project
Many parents do not fully follow UK NHS safer powdered infant formula preparation guidelines, potentially leading to gastrointestinal infections.
Non-RCTIs bottled water really unsafe for making up infant formula?
The NHS' advice against using bottled water for infant formula is not justified, and there is a need for improved information and training for healthcare professionals to protect infants.
Time for the 70 °C water precautionary option in the home dilution of powdered infant formula
Using hot water at 70°C for dilution of powdered infant formula is recommended to prevent Cronobacter sp. contamination and growth.
Rigorous JournalThe use of moisture sorption isotherms and glass transition temperature to assess the stability of powdered baby formulas
Powdered baby formulas' stability can be assessed using moisture sorption isotherms and glass transition temperature, with critical water activities ranging from 0.14 to 0.68 and moisture contents from 0.032 to 0.062 g g1 powder.
Water supplementation in exclusively breastfed infants during summer in the tropics
During summer in the tropics, exclusively breastfed infants do not need supplemental water to maintain water homoeostasis, but reduced breastmilk intake may be a disadvantage.
RCTHighly CitedDetermination of water content in infant formula
The reference method, classical Karl Fischer titration, is the most accurate and fastest method for determining water content in infant formula, while oven sample processor, halogen drying, and drying oven methods require heating for extraction.
Water and formula fluoride concentrations: significance for infants fed formula.
Water fluoride levels play a significant role in the dental fluorosis risk for formula-fed infants, with bottled water and soy-based formulas contributing to the total fluoride intake.
Observational StudyHighly CitedInfant burn injuries related to water heating for powdered infant formula preparation
Powdered infant formula preparation guidance should consider both Cronobacter infection and burn risks, as water heating for preparation can cause minor injuries in infants aged 18 months.
Observational Study