Sharon Trotter RM BSc

Cup feeding revisited

This draft article was published in the September issue of the MIDIRS Digest. The full reference is: Trotter S. MIDIRS Midwifery Digest, vol 16, no 3, September 2006, p397-402

Key points
Introduction
Early indications for cup feeding
Dental caries and lidded cups: the evidence
What about full-term breastfeeding?
New directives
Speech difficulties?
Poor nutrition and Iron Deficiency Anaemia (IDA)
Bacterial contamination of cups
What's in a cup?
Safe alternatives
Conclusion

Key points

• Breastfeeding not only provides the best nutrition for a baby but also conveys physical and emotional benefits that will last a lifetime.
• Cup feeding (using open cups in specific circumstances) is safe from birth and is less likely to interfere with the establishment of breastfeeding.
• Weaning to solid foods should not be started before six months.
• From six months, and within a supervised environment, infants should be encouraged to drink rather than suck.
• Use open cups made from polypropylene, polyethylene, polyethersulfone or glass.
• Consider using ceramic plates, cups and bowls.
• By one year old a child should be actively discouraged from using any lidded feeder. Meanwhile baby-led breastfeeding should be encouraged.
• The fostering of good eating habits from a young age will pay dividends in the long term and avoid the risks of obesity, IDA and speech difficulties.
• Dental hygiene must be seen as a priority. Regular oral care and visits to the dentist are vital.
• Remember that nutrition is more than just food. It is a social experience that should be shared and enjoyed by all members of the family. [back to top]

Introduction

As founder of TIPS Ltd my mission statement is:
To educate and inform parents and professionals about best practice in breastfeeding, neonatal skincare and cord care, and other related midwifery subjects.
Cup feeding would appear to be an innocuous subject and you may wonder why I am devoting so much time to it. When researching for this piece, I did not imagine there could be so many potential hazards associated with this practice.
Cup feeding has been around for centuries. It's only in the past 50 years that bottles, teats and cups with spouts and lids have dominated western cultures.
At this point it is important to distinguish between the two types of cup feeding. One is used in the early weeks of life, when an alternative form of feeding is required, until breastfeeding is established. In this instance, cup feeding with a small 'medicine' style beaker works well .
Secondly, from six months of age, once solid foods have been introduced, cup feeding, using an open cup, can complement breastfeeding or give an alternative to the bottle. This will help to maintain breastfeeding and fulfil the UK Committee on Medical Aspects (COMA 1994) recommendation that bottles should be discontinued by the age of one year.
One of the many benefits of breastfeeding is its action in stimulating the muscles of the tongue and oral cavity while babies suck. This complex mechanism helps to shape the jaw and teeth, and develop optimum muscle and tongue strength (Palmer 1998). When babies suck on a bottle or spout, their mouth is partially closed. Their jaw, mouth and tongue muscles are not encouraged to work as hard. Consequently, the transition to breastfeeding, after a time of bottle use, can be problematic. For this reason the World Health Organization (WHO 2004) recommend cup feeding (open design) as the most suitable alternative, when direct breastfeeding is not possible.
As a passionate advocate of breastfeeding (Trotter 2004), I am keen to dissuade parents from using bottles, teats, spouts and lidded cups for at least the first six months of life (unless for specific indications, as described below). However, once weaning begins parents are drawn to all manner of designer cups with spouts and one way valves etc as a way of feeding their babies drinks. When my children were small, even I admit to having the ubiquitous collection of plastic receptacles in various shapes, sizes and colours of the rainbow. This is now big business with industry-wide sales running into millions for lidded cups. Modern family life is busy and much time is spent on the move. Parents feel the need to buy cups that have non-drip lids or one-way valves to stop leaks in cars or on furniture.
Maybe the time has come to reflect on the potential consequences of this seemingly innocuous trend on our children's health. Are lidded cups even necessary? Are there implications for oral health, speech and emotional development? Are these cups safe to use or could they harbour harmful bacteria? If we are to encourage bottle-fed babies to drink from open cups, what are the implications for those breastfeeding beyond six months? This article will address these issues and propose evidence-based advice for parents and professionals to follow. [back to top]

Early indications for cup feeding

In the early weeks of life, the objective of cup feeding is to safely feed a baby expressed breast milk until he is able to take all feeds by breast. Cup feeding is a skill easily acquired from birth, even by premature babies (Lang et al 1994). Indications for this form of feeding include:

• Preterm babies after 32 weeks gestation - this is the time when babies are able to co-ordinate their suck, swallow and breathing reflex (Lang et al 1994);
• Preterm infants who are alert and looking for a feed but who do not have the energy to complete a full breastfeed (research shows that heart rate, respirations and oxygen requirements are better maintained within normal limits during cup feeding in comparison to bottle feeding (Lang 1994));
• Infants with cleft lip or palate before corrective surgery;
• Conditions in which infants' sucking ability may be compromised such as Down's syndrome or other neurological impairment;
• Infants born to mothers who are temporarily unable to breastfeed, for example delayed recovery from surgery;
• Maternal conditions such as nipple damage or inversion that temporarily prevents direct breastfeeding (whilst mother still expresses);
• Short-term conditions affecting the infant such as breast refusal due to traumatic early exposure to the breast or drowsiness caused by opiates during labour or excessive jaundice (physiological jaundice should not cause drowsiness - it only occurs when normal limits become abnormal);
• For mothers who are returning to work before their baby is six months old but who wish to continue breastfeeding, expressed milk can be given using an open cup. In this instance it may be wise to introduce the cup a few days before the first shift so the baby can become accustomed to it.
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Dental caries and lidded cups: the evidence

From six months of age the objective of cup feeding is different from that of the neonatal period. At this stage, progression from sucking to drinking is paramount. An open cup or, at the very least, a free-flowing feeder is therefore recommended.
A number of papers linking use of lidded cups to dental caries have been published (Cone 1981, Errant 1992, Kovesi 1992, Roberts et al 1993) and the terms 'nursing bottle caries', 'sucking cup caries' and 'early childhood caries [ECC]' (Reagan 2002) have been coined. These terms are now synonymous with inappropriate feeding practices (Ripa 1988).
The cause of such caries is thought to be the pooling of formula milk or sugary drinks in a baby's mouth. Bacteria called streptococcus mutans thrive in a combination of sugars, low levels of saliva and a low pH level in saliva. This produces high levels of acid which destroy tooth enamel. The bacteria are spread by saliva to saliva contact with adults already infected. They do not colonise a baby's mouth until their teeth appear. Close contact and kissing is obviously impractical to avoid with young babies and there is reassuring evidence to support the immunisation effect of this contact before a baby's teeth erupt (Aaltonen 1994). Levels of this bacterium have been found to be more than 100 times higher in children with caries than those without (Reagan 2002).
The risk of a child developing dental caries is greatly increased by grazing on sugary drinks or formula feeds, which, in contrast to breast milk, are known to be particularly corrosive to enamel (Erickson 1998).
So what of full-term breastfeeding, especially night time feeds, which can be regular and go on for years?
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What about full-term breastfeeding?

Unlike bottle feeding, breastfeeding does not cause dental caries. The reasons for this are varied.
When breastfeeding, babies suck and swallow simultaneously. Breast milk enters the mouth behind the teeth and does not pool in a baby's mouth (Bonyata 1998).
Antibodies (IgA and IgG) in breast milk counteract bacteria in the mouth and lactoferrin actually kills streptococcus mutans (Arnold 1977).
In vitro breast milk has also been shown to remineralise artificially demineralised enamel (McDougall 1977). This was further corroborated by Erickson (1999), who soaked extracted premolar crowns in different solutions and found that the breast milk caused no decay. In fact, the tooth appeared to be stronger after immersion. Dr Tinanoff (1997) also concluded that after five minutes of breastfeeding, the pH level in a baby's mouth was only slightly changed against being rinsed in plain water.
Eminent American dentist Brian Palmer (2000) goes further stating that "Empiric evidence does not support a causal association between breastfeeding and infant caries", concluding that: "breastfeeding truly is the best and cheapest form of health insurance". [back to top]

New directives

In 1994, as a result of the earlier studies, the UK Committee on Medical Aspects (COMA 1994) published their weaning report. This publication advocated the introduction of solid foods from four to six months. The report strongly recommended that infants older than six months should be introduced to drinking from a cup and suggested that the use of bottles be actively discouraged from 12 months. While the document refers to 'bottles and reservoir feeders', it must be emphasised that any vessel which is designed to encourage frequent sipping has the potential to damage oral health, interfere with oral muscle development and may even have a detrimental effect on speech (Eig 2002). Only open cups can truly be seen to fulfil the criteria for encouraging drinking rather than sucking.
In 2001, the WHO changed its recommendations on weaning to advocate exclusive breastfeeding for the first six months of life, with the introduction of complementary foods and continued breastfeeding thereafter (WHO 2001).
The Scientific Advisory Committee on Nutrition (SACN 2001), the body replacing the COMA panel on child and maternal nutrition, responded to the WHO recommendations in September 2001. It now agreed that:
"Mothers of infants should be particularly warned of the dangers of putting fruit juice or sugar-sweetened drinks into feeding bottles or reservoir feeders for the child to hold, especially in bed. Such practices result in almost continuous bathing of the enamel with sugars and lead to severe tooth decay".
These 'nursing bottle caries' are not just detrimental to a child's physical health; the increased need to undergo surgery for tooth extraction at a young age also has obvious psychological repercussions.
In the States, the American Academy of Pediatrics (AAP 2003) do not differentiate between formula feeding and breastfeeding when they conclude that children who sleep with a bottle or breastfeed throughout the night are at risk of developing ECC. Evidence is clear regarding the vast benefits of baby-led breastfeeding and future policy needs to reflect this.
The American Academy of Pediatric Dentistry (AAPD 2003) also recommends that "nocturnal breastfeeding should be avoided after the first primary tooth begins to erupt". As this could occur before six months of age, this advice could contradict that of the WHO (2001). Consistency is vital when new directives are published and communication between agencies will help to avoid confusion for parents and professionals.
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Speech difficulties?

Although evidence is mostly anecdotal, it has been suggested that there may be a link between inappropriate infant feeding and later speech development. Selley et al (1990) identified seven common factors in co-ordinated neonatal feeding and speech production, namely: rhythm, breath-control, lip tone, delicate tongue movements, speed of muscle movements, well developed sensory feedback and a relaxed feeding situation. Breastfeeding and open cup feeding fulfil these criteria by encouraging development and maturation of these factors, while promoting a positive feeding experience.
Some speech therapists still believe that the action of drinking from a lidded cup can interfere with the more complex swallow required when using an open cup. The latter action helps to build the muscles required for proper speech to develop.
Sara Rosenfeld-Johnson, a speech pathologist from Tucson, Arizona, presents seminars around the USA and is one of the most outspoken critics of the 'sippy cup'. She does however concede that those speech anomalies are easily treated by switching back to regular open drinking cups (Eig 2002). [back to top]

Poor nutrition and Iron Deficiency Anaemia (IDA)

Nutrition is only one facet of the feeding process. Comfort, security, closeness, bonding, sociability, self-confidence and love all develop through appropriate feeding practices. After all, eating is a highly social experience that should always be shared with other members of the family. This is not only enjoyable for the child but will instil good eating habits from an early age. Breastfeeding is obviously the optimal method of feeding (WHO 2001) but close supervision of cup feeding, using an open design, will do much to engender the closeness of breastfeeding.
Iron deficiency anaemia (IDA) is particularly prevalent in UK Asian communities.
Published research (Williams & Salota 1990, Harbottle & Duggan 1992) appears to show a link between the consumption of sweetened milk and tea given from a bottle and poor dietary habits leading to IDA. Children who derive a high proportion of their energy requirements from drinks alone are less likely to develop good eating habits or have a balanced diet. This is because their appetite is suppressed by sugary drinks which their mothers (supported by their family) believe are nutritious. Red meat is a good source of iron. However, prolonged bottle feeding delays the development of chewing skills and good dietary habits are not fostered early enough to avoid the development of IDA. The common use of sweet tea, which contains tannins, can also be responsible for limiting the amount of iron that is absorbed. If required, and to aid iron absorption, fresh orange juice (diluted to ten parts water) could be offered at mealtimes from an open cup.
Although failure to thrive and poor weight gain are associated with IDA, it is worth pointing out that long-term obesity and eating disorders are more common if early nutritional complications are not recognised and treated. [back to top]

Bacterial contamination of cups

Finally, there is the potential hazard for children to become ill as a result of contaminated lidded cups. Unless great care is taken to clean bottles and cups, an unsuspecting child may find a lost cup, hours or even days after it was used. If the child then sucks on this drink there is a high chance it will be contaminated.
In her recent survey, Ms Adams, a news reporter in Louisville, USA, found that infant lidded cups tested at laboratories, were teeming with bacterial growth (Eig 2002). This may seem extreme but should be a cautionary tale for any parent. [back to top]

What's in a cup?

What materials are used in the manufacturing process of plastic cups? Are they safe? Most commercially available bottles and cups are made from polycarbonate. When heated there is the potential for migration of the chemical Bisphenol-A (this is a chemical softener) from the container into the contents. This is less likely to occur when a bottle or cup is new, but old or scratched containers may be more likely to leach. The levels of this hormone-like substance found under test conditions are very small, but as babies' immature systems are more sensitive to chemicals, there is no safe limit. It is therefore prudent to keep any exposure to an absolute minimum. It may be wise to rinse thoroughly any container that has been unused for a period of time, with plain water, to aid the removal of any residues that may be present. [back to top]

Safe alternatives

It may be advisable to opt for bottles or cups that are made from polypropylene, polyethylene, polyethersulfone or glass. Advice to mothers, if they are not sure what material a bottle or cup is made from, should be to avoid abrasive scrubbing and to change them every six months. Also, old bottles from a previous baby should not be kept. They may have deteriorated with age.
In the UK, a company recently launched a new design of cup called the 'Doidy' cup. This is manufactured from high density food grade polyethylene, and conforms to current EN14350 regulations. It has also been tested by two independent laboratories. The open slanted rim allows the contents to be seen but not spilled and the two handed design makes the cup easy to hold.
Feeding bowls and utensils are also likely to be made from plastic. So, once again, parents should check the materials these are made from and if they are not listed, the manufacturer should be asked for the information. Ceramic plates and cups are a good alternative to plastic ones. They are perfectly safe and can withstand the microwave and dishwasher and ranges of ceramic bowls are becoming more available.
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Conclusion

Some would argue that it is not just the design of the bottle or cup but the contents that matter. This may be true, and offering only milk or water (Emmett et al 2000) at mealtimes in lidded cups will certainly help to reduce any potential risks associated with them. Nonetheless, common sense tells us that the sooner open cups are introduced, the sooner the infant will develop the skill to drink and not just suck. This will benefit the development of speech, reduce the risk of IDA and potentially instil good eating habits for the future.
Cup feeding can be extremely useful at certain times in an infant's life. In the early days, it can bridge the gap between supplementation (for whatever reason) and the establishment of breastfeeding. Once weaning has commenced it will help the child to progress from sucking to drinking.
The establishment of good eating habits is a key to good nutrition and modern day lidded cups have the potential to negatively affect this transition. [back to top]

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