Artificial baby milks:
how safe is soya?
by Tessa Martyn, a freelance writer on
infant feeding issuesand a former health campaigns
coordinator for Baby Milk Action.
article first appeared in RCM Midwives Journal.
Copyright RCM. Not to be reproduced without first contacting
the article as a pdf file click
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toxicology experts have recently confirmed concerns over
the potential health risks of soyabased
artificial baby milks. This may come as news to many – especially
who freely recommend it, or parents who can buy it off the
shelves (no questions asked)
believing it to be a healthy option. Soya is generally viewed
as a healthy food, and for adults
there are some reported health benefits. However, human infants
were ‘designed’ to drink
human milk, and soya-based milk products are a far cry from
The list of concerns about soya-based artificial baby
milks is extensive: the high levels of phytoestrogens,
possible presence of genetically modified (GM) soya, the
glucose content and the large quantities of metals such
as aluminium, not to mention the fact they do not
contain any of the health-protecting immune factors and
live cells that breast milk has in abundance (New
Zealand Ministry of Health, 1998; Baby Milk Action,
It is estimated
that 2% of all infants in the UK are fed soya-based milks
(Ministry of Agriculture, Fisheries and
Food (MAFF), 1998; Hamlyn et al, 2002). The soya-based
baby milk market in the UK is worth approximately £6
million (the total baby milk market is worth over £150
million (Unsworth, 1998)).
In recent years
the possible risks associated with the use of soya products
for infants have had much media
attention. Headlines have included: ‘Is baby food
safe? New GM shock’ (Daily Express 17 February
What your baby’s drinking now: genetically altered
beans, squeezed tuna fish heads?’ (The Observer 21
December 1998)and ‘Warnings on danger of soy formula
milk’ (Sunday Herald 25 August 2002).
It is all health
professionals’ responsibility to
to date in all areas, and infant feeding is no exception.
This article aims to outline some of the evidence about
the risks involved in using soya – not only when
baby milk is soya-based, but also when soya is used
as an ingredient in standard modified cow’s milk,
in the form of soya lecithin (an emulsifier). The two areas
of concern addressed here are the presence of GM soya,
and high phytoestrogen levels.
Genetically modified soya in baby milks
biotechnology continue at a fast pace – but
at what cost? Are the companies involved (such as
Monsanto and Novartis) running before they can walk?
The ongoing debate about the use of genetically modified
(GM) products in foodstuffs has highlighted the extent
which consumers have been kept largely in the dark.
especially soya and maize, are now in so many products
that it is difficult to avoid eating them,
and baby milks and foods are no exception. Infants are
particularly vulnerable as they have no choice – their
parents choose for them.
Scientists have been debating the safety of GM products
for years. Some claim that they cause no harm,
others believe that the use of GM foods could create
new toxins, damage the immune system and possibly cause
cancers and allergies.
Of crucial importance in this debate is the fact that
adults have a far more varied diet than infants, so
GM soya, or even traces of GM soya, are likely to affect
infants to a much greater degree. For infants fed exclusively
on soya-based baby milk, soya constitutes practically
all of their diet. The effects of this on the
development of the child, both in the short and long
term, is unknown. However, infants are thought to be
more susceptible to harm because their immune systems
Under European Union (EU) legislation
passed in 1998 it is a legal requirement for
producers to state on the label if food
contains GM products. However, there are
loopholes in the legislation, which means
that ingredients such as additives and
lecithin are not included. So companies do
not have to label their products as containing
GM soya if they only contain soya lecithin.
In 1999 Baby
Milk Action, a UK-based group campaigning for safer infant
surveyed the leading UK artificial baby milk
companies to find out if they claimed their
artificial baby milks (both soya-based and
modified cow’s milk), were GM free or not.
This survey was conducted in response to
numerous calls from worried parents.
At that time
Heinz Farleys, Cow & Gate
and Milupa claimed that they did not use
soya from GM sources.Mead Johnson failed
to respond and SMA admitted that they had
used GM soya in 1997, but withdrew it due
to consumer concern (Baby Milk Action,
In October 2002 the companies were asked
once again whether or not they used GM
soya. This time Mead Johnson did reply,
saying they did not use GM soya in Prosobee
(although the Greenpeace True Food
Network believes otherwise (see www.
truefoodnow.org), but SMA declined to
This is worrying,
not only in the light of SMA’s past history of using GM soya in artificial
baby milks, but also because their
parent company Wyeth has sponsored
research for a company called PPL
Therapeutics in Virginia, US. A PPL
spokesperson, David Ayares, said they are
aiming to develop ‘a completely humanised
milk product where you would milk a cow
and almost human milk would come out...
We now have a mini-herd of transgenic
cattle that are making human alphalactalbumin...
in their milk.’ The new GM
human-cow’ milk was due to be on the
market midway through 2002 (Baby Milk
At the dawn of a new millennium it is
science fiction at its most scary that such a
basic physiological, purely natural function
and fluid is being replaced by milk from
science writer Moyra Bremner (1999) writes: ‘Solving these problems
[increasing the number of babies who
receive breastmilk] by engineering a bull to
create cows with human milk is like losing
your front door key and hiring a Sherman
tank to get you in, instead of going to a locksmith.
It may be rather fun to use a tank – but is it wise?’
Phytoestrogens in soya in baby milks
are naturally-occurring plant chemicals found in a wide
variety of edible
plants. They are present in high levels in soya
beans (the term isoflavone is sometimes used – these
are a class of phytoestrogens that occur naturally in soya
Phytoestrogens have oestrogenic properties,
similar yet less potent than the female
Infants being fed soya-based artificial baby
milks receive the equivalent level of phytoestrogens
(per kg body weight) of several
contraceptive pills every day (Irvine C et al,
the US found that soya-based baby milks contained six
to eleven times the
amount of phytoestrogens known to cause
changes to menstrual cycles (Setchell K et al,
1997). This same study also measured the
levels of phytoestrogen in the plasma of
four-month-old boys; in those babies receiving
soya-based baby milk the levels were 200
times higher than those taking breast milk
(levels in breast milk were found to be negligible).
The authors conclude: ‘Long term
follow-up studies are needed to assess the
potential benefit or adverse effects of phytoestrogens
exposure in early in life.’
of research studies (dated between 1953 and 2002) looking
at the effect
of phytoestrogens has recently been
compiled (Weston et al, 2002). The studies
all demonstrate the adverse effects of phytoestrogens,
such as increases in cancers,
changes in DNA structure, early thelarche
(prepubertal development in girls), fertility
problems, liver disease – and the list continues.
A total of 59 of these studies have been
published during or since 1999 – this alone is
evidence that the concern about phytoestrogens
in the diet is ongoing.
a spokesperson for the Infant and Dietetic Foods Association
organisation representing the artificial baby
milk and food industry in the UK, claimed
that soya-based artificial baby milks are ‘safe
and that infants thrive well on them’ (Jacobs,
vast majority of the studies included in the bibliography
rodents and other mammals, there are
obvious concerns about the extent of possible
health risks to human infants. Dr Tracie
Sheehan of the US Food and Drug
Administration’s National Center for
Toxicological Research stated that infants fed
soya-based baby milks have been placed at
risk in ‘a large, uncontrolled and basically
unmonitored human infant experiment’ (The Food Commission,
In the mid-1980s
evidence indicated that there was a ‘positive statistical association
between premature thelarche and the
consumption of soy-based formula, various
meat products, and a maternal history of
ovarian cysts’ (Freni-Titulaer L et al, 1986).
By the early
1990s concern about the effect of dangerously high levels
in soya-based artificial baby milk had escalated,
so in 1992 the Department of Health’s
(DH) committee on toxicity of chemicals in
food, consumer products and the environment
(CoT) called for monitoring and
review of phytoestrogen levels in soya-based
baby milks. The resulting report, commissioned
by MAFF, was not released until
Meanwhile the CoT had reviewed the
existing literature and concluded not only
that further research was required, but also
that the use of soya in baby milks may be
harmful. In response to this, in 1996, the DH
issued a press release recommending that:
- Infants already being fed soya-based artificial
baby milks on the advice of a health
professional should continue to do so
- Infants being fed soya-based milks
without the advice of a health professional
should continue to do so, but,
professional advice should be sought.
The DH also
reaffirmed that breastfeeding is the best way to feed
an infant and can help
prevent allergies, and that if an alternative is
required then modified cow’s milk is preferable
for most infants.
Prior to the press release being issued the
DH had sent an urgent ‘cascade’ circular
to all health professionals warning of the risks
associated with the use of soya-based baby
milks and advising that it should only be
used on the advice of a health professional in
funded by MAFF (released in 1998) had measured levels
in three major brands of commercially available
cow’s milk formula and six brands of
soya-based baby milk bought in the UK
between March 1996 and July 1997. The
results were similar to those found in the
Setchell et al (1997) study. Once again the
DH endorsed the advice given in its 1996
In April 2000, following new research and
continuing concern over the health effects
phytoestrogens for infants, the CoT
convened a working group to advise on the
human health implications of dietary
One of the main
questions to be addressed was: ‘On the basis of current evidence, does
ingestion of soy-based infant formula pose
any risk for human infants?’ (Food Standards
Agency (FSA), 2002). The draft report was
available for consultation for eight weeks
from October 2002 (see the website www.foodstandards.gov.uk).
Regarding the specific question of risk to
human infants fed soya-based artificial baby
milks, the working group draft report had six
key points. These are shown in the box.
Infants fed soya-based
artificial baby milks are exposed to the highest
phytoestrogens (compared to other population groups,
e.g. breastfed babies, adults
As only one study has specifically examined the
long term health effects of soya-based artificial
baby milk, it was acknowledged that it was difficult
to draw conclusions (particularly as this
study relied on recall)
Health professionals should be made aware of
the potential interaction between phytoestrogens
in soya-based artificial baby milk and thyroid
Further, infants with congenital
hypothyroidism who are fed soya-based artificial
baby milks should have their thyroxin levels
Human infants fed soya-based artificial baby
milks appear to have normal immune function
(studies in rodents have shown potentially
adverse effects to the immune system)
The outcomes of an ongoing study looking
at the effects of feeding soya-based milks to
marmosets (and particularly changes to reproductive
health) should be carefully evaluated on
and perhaps most importantly, the working group
recommended that the advice
issued by the DH in 1996 should
be amended to state that soya-based artificial
baby milks should only
be used when ‘indicated clinically’.
It is also noted that similar advice
has already been issued in
some countries, eg Australia and New
Zealand (in New Zealand the Ministry
recommends that soya-based artificial
baby milks are only used in very limited
and always under the direction of a health
professional. Even though soya-based
could be used for lactose intolerance,
the Ministry states that alternative
baby milks exist and
their use should be favoured over a soya
product. Additionally, infants with hypothyroidism
should not be fed soya-based baby milks
unless no alternative can be found).
What needs to be done
The remit of the CoT working group was
risk assessment. It is up to the FSA and DH
to decide, on the basis of this report, what
action needs to be taken.
the FSA follows the recommendations of the CoT working
group by ensuring soyabased
artificial baby milks are only used
when ‘indicated clinically’, then changes will
have to be made to the way that soya-based
artificial baby milks are marketed.
At the moment soya-based artificial baby
milks are available in supermarkets and
pharmacies and are promoted to health
professionals. Parents can feed their babies
soya-based artificial milk without ever
having consulted a health professional and,
as the products carry no appropriate warnings,
they will be none the wiser about the
possible adverse health effects. Parents at
particular risk in this category include
vegans, those who drink (adult) soya milk
and assume that their baby will also gain
health benefits from drinking soya-based
artificial baby milk, and the seemingly
increasing number of parents who have been
told (or who believe) their baby is lactose
intolerant and therefore needs a dairy-free
substitute for breast milk.
incidence of true lactose intolerance is low, although
advertising by the artificial
baby milk companies suggests otherwise.
Companies advocate the use of soya and
other artificial baby milks as the answer for ‘
problem babies’, rarely warning about the
risks. Advertisements in health professional
journals tend to gloss over any potential
problems with the use of soya and portray it
for use in many circumstances such as diarrhoea,
colic and eczema. Breastfeeding,
particularly exclusive breastfeeding, is proven
to reduce the incidence of atopic disease,
but this fact is not widely understood or
The most obvious change necessary in the
marketing of soya-based artificial baby milks
is that they should become a prescriptiononly
item. This would prevent off-the-shelf
purchases and parents using them without
having discussed it first with a health
there are still so many unknown factors about the effect
of soya on young
infants, all infants using it should be monitored – this
would be easier if the product was only obtained on prescription.
A weaker option is that soya-based artificial
baby milks could become an over-thecounter
item in pharmacies, like many
painkillers. This would mean that the sale of
them would be monitored to some degree by
The DH and FSA should ensure that
health professionals are provided with clear
guidance and information about the possible
risks associated with the use of soya-based
artificial baby milks. Such guidance should
be continuous rather than one-off, so that
health professionals can give up-to-date and
correct information to parents.
The artificial baby milk companies themselves
should ensure that labels and other
sources of information highlight both the
known and the potential risks of soya products
in foods and drinks for infants.
a precautionary measure the artificial baby milk companies
should be required to
seek ways of reducing the levels of phytoestrogens
in their products – as requested by
the MAFF food advisory committee in 1996.
Food Commission, in their own 1998 investigation, found
that companies had
failed to respond to this demand and that
they ‘blocked direct enquiries’. They have requested
that phytoestrogens are removed
immediately from soya-based infant baby
milks, as they believe ‘it is irresponsible for
manufacturers of soya formulas to continue
to place infants at unnecessary risk of exposure
to phytoestrogens’ (The Food
In 2002 the Committee on the
Convention on the Rights of the Child (the
body responsible for ensuring that children
can have the highest attainable level of
health) specifically recommended that the
UK government implemented the WHO
International Code of Marketing of
Breastmilk Substitutes. If this were done,
then parents and health professionals would
be spared the potentially misleading information
distributed by artificial baby milk
companies, and labelling would be
improved so as to advise users of the possible
health risks of using particular products.
This in turn would not prevent genuine
scientific and factual information from
being given to parents and health
are in a key position when it comes to advising parents
feeding. This is not an easy task. The journals
are full of advertisements – often with scant
information, and very little information is
available from independent sources.
Midwives need to demand their right to
have access to the best available information
and research.Without this, both midwives
and parents will remain oblivious to the
chemicals and hormones that we are putting
into the mouths of our babes.
This is an updated version of an article
that appeared in The Practising Midwife in June
Baby Milk Action. (1994) Glucose in soya
and milks. Update March: 3.
Baby Milk Action. (1999) Baby milk company
responses regarding soya in artificial baby milks. Baby Milk Action: Cambridge.
Baby Milk Action. (2000) Mutant baby milk.
Update 27: May.
Bremner M. (1999) GE: Genetic engineering
and you. Harper Collins: London.
Department of Health. (1996) Advice on
soyabased infant formulae. Press release (96/244),18/06/96.
Food Standards Agency. (2002) Background
information on the CoT Working Group on phytoestrogens
and draft report. 09/10/02. FSA: London.
LW, Cordero JF, Haddock L, Lebrón
G, Martínez R, Mills JL. (1986) Premature
thelarche in Puerto Rico: a search for environmental
factors. American Journal of Disease
Control 140: 1263-4.
Hamlyn B, Brooker S, Oleinikova K,Wands S.
(2002) Infant feeding 2000. TSO: London.
Irvine C, Fitzpatrick M, Robertson I,Woodhams
D. (1995) The potential adverse effects of
soybean phytoestrogens in infant feeding. New
Zealand Medical Journal 108(1000): 208-9.
Jacobs S. (1999) Letter in Practising Midwife,
written in response to article: Martyn T. (1999)
Soya in artificial baby milks. Practising Midwife 2(6): 16-9.
Ministry of Agriculture Fisheries and Food.
(1998) Soya-based infant formulae. Food safety
information bulletin. 10 November. MAFF:
New Zealand Ministry of Health. (1998) Soya-based
infant formula. New Zealand Ministry of
Setchell KD, Zimmer-Nechemias L, Cai J, Heubi
JE. (1997) Exposure of phyto-oestrogens from
soy-based formula. Lancet 350: 23-7.
The Food Commission. (1998) Baby soya milks:
companies fail to act. The Food Magazine 43: 3.
The Food Commission. (1998) Phytoestrogen
levels to be published. The Food Magazine 43: 8.
Unsworth R. (1998) Milking the baby milk
market. Mail on Sunday 20 December: 26.
Weston A. (2002) Price foundation and
soy information network. Bibliography – compiled
for US lawyers, emailed to author, November 2002.
Useful websites for further information
UPDATE *** UPDATE *** UPDATE *** UPDATE
Just before this article went to press, the CoT
requested that the scientific advisory committee on
nutrition (SACN) examine their draft report on
CoT report had stated that soya-based artificial baby
milk should only be used ‘when clinically
indicated’. On this point SACN noted that ‘there
appears to be no unique clinical indication for soybased
formula’ (see the website www.food.gov.uk/science/ouradvisors/toxicity/cot
This therefore raises the question of whether
soya-based artificial baby milks should exist at all,
given their potential health risks.
The final report is due out in mid-2003.
It will then be up to the FSA and the DH to act on these
findings to ensure that parents and infants are
protected from an unnecessary health risk.