Tag Archives: evidence-based

What not to do during pregnancy and childbirth

Ben Goldacre – author of Bad Science, scourge of secretive Pharma companies, and champion of evidence-based healthcare – highlighted a great resource on his secondary blog. It is a collection of ‘do not do’ recommendations from the National Institute for Health and Clinical Excellence (pleasingly abbreviated to NICE), which publishes guidelines on best healthcare practices within the UK’s National Health Service.

The ‘do not do’ database holds information on a range of clinical practices that NICE recommend should be stopped or not used routinely, all of which is based on the best available evidence. There is a section on ‘Gynaecology, Pregnancy and Birth’, which contains 174 recommendations. Many are for specific interventions that may be more of interest to health professionals, such as “A serum ferritin test should not routinely be carried out on women with heavy menstrual bleeding (HMB)”. But there are a few nuggets that mothers- and fathers-to-be may like to hear.

There is a range of advice on alternative and complementary therapies, for instance: “Healthcare professionals should inform women that the available evidence does not support herbal supplements, acupuncture, homeopathy, castor oil, for induction of labour”. There is no evidence for hot baths, enemas or sexual intercourse either. For labour pain, transcutaneous electrical nerve stimulation (TENS) should not be offered to women in established labour”, which our midwife obviously had not read (or just ignored!).

As for acupuncture, acupressure and hypnosis, they “should not be provided, but women who wish to use these techniques should not be prevented from doing so”, which seems sensible, although potential side effects should be forgotten. Generally for alt med, it advises that: “Pregnant women should be informed that few complementary therapies have been established as being safe and effective during pregnancy. Women should not assume that such therapies are safe and they should be used as little as possible during pregnancy.” Sound  advice.

There is a mention of supplements during pregnancy – iron supplements shouldn’t be taken routinely (unless a deficiency is identified) – but I would love to see that section expanded to cover other areas of nutrition. More specifically, there is no good evidence that magnesiumfolic acidantioxidants (vitamins C and E), garlicfish oils or algal oils can help prevent disorders related to high blood pressure, such as pre-eclampsia.

A random titbit that’s not really connected with other recommendations, says that if a women wants to breastfeed, then breast examination during pregnancy does not seem to help breastfeeding in the long run.

There are more pieces of intriguing guidance about midwife support during labour (“Team midwifery and active management of labour), psychosocial interventions to reduce the likelihood of developing a mental disorder, and approaches to fertility problems.

All of which can only be good for mums and dads in making informed decisions and for health professionals in providing the best care possible. Happy browsing!

Telly addicts: alarm over kids’ TV viewing habits

There was a flutter of activity across Twitter and blogs the other day, in response to some reports that suggested kids’ increasing TV viewing was having a detrimental effect on mental health. According to the reports, TV viewing should be limited for children even into their teens and banned altogether for under-threes. The issues highlighted here will be familiar to detractors of Bad Science and Bad Reporting, but I wanted to record some thoughts for posterity.

I first saw the story in The Guardian and it was also picked up by BBC News, The Independent, The Telegraph, Daily Mail, Metro and many other outlets. Whilst it’s an interesting and worthwhile area of study, the paper published in the journal Archives Of Disease In Childhood and the subsequent press statements, had a few problems that undermine the stark headlines.

The paper was not an original research paper, but an opinion piece that looked back at some previous research. The chief agitator in this is Aric Sigman, a psychologist whose method of ‘cherry-picking’ evidence Ben Goldacre has had much to say about in the past. ‘Cherry-picking’ is essentially picking the bits of evidence that support a particular claim, whilst ignoring other evidence that doesn’t. As Goldacre points out, a better way to analyse previous research is to perform a ‘systematic review‘. These reviews say exactly how the literature was searched and compiled, which means it is more free from bias and allows others to reproduce it.

As for this specific case, Pete Etchells at SciLogs does a good job at highlighting the problems with the selective nature of the analysis and why it’s important to understand the cause of something before issuing guidance on fixes. I worry that many developmental outcomes – such as empathy, attention, educational performance – are lumped in under the banner of ‘mental health’, but that is probably for someone more qualified to comment on. Professor Dorothy Bishop‘s remarks in the Guardian article are salient too – if Sigman’s concerns are to do with kids just sitting for long periods, you shouldn’t advocate reading books for too long.

My first thought on reading the reports was that the conclusions seem to be based entirely on correlative studies, so it’s hard to determine cause-and-effect. What if children who watch more TV are also more likely to have inattentive parents? You may still see an association between more TV watching and developmental problems if these are both caused in some way by inattentive parenting, but enforcing a reduction in TV time wouldn’t do anything – getting parents to interact more at other times would have the most effect. (For the record, this is just an example of ‘correlation does not imply causation’ and I’m not suggesting this is supported by the evidence!)

On a more general but related point, there is a real problem with defining ‘screen time’, because you’re essentially describing a medium and not an activity. The Mind Hacks blog (written by KCL psychologist Vaughan Bell and Sheffield University psychology lecturer Tom Stafford) has written about this in relation to internet use. Bell has also written about how there have been worries throughout modern history over new technology. Even ‘education’ was once considered a risk to mental health.

As for TV, there are clearly different types of programmes kids can watch – some are aimed at learning and education, some are musical and participatory, some are interactive, and so on. And there are also different contexts in which to watch TV – alone, with parents talking things through, in the background whilst doing other things, etc. Understanding whether different types of TV interaction have different effects or whether other factors in the child’s environment tend to lead to a particular sort of behaviour, are critical in getting to the root of the issue.

The evidence just isn’t strong or reliable enough to make the sort of alarmist claims Sigman has made. And this is why it is again so disappointing to see the same blanket coverage across much of the press, with little in the way of a proper critique (Prof Bishop’s comments aside). It was once again left to bloggers and commentators on social media to provide a more discerning look at the issues.

I want to emphasise that I’m not dismissing these issues, and there may well be problems caused by excessive use – however that’s defined – of certain types of ‘screen time’ (as Etchells notes too). But it’s important to know what you’re measuring and understand the nuances. It is also crucial to have proper evidence before issuing supposed evidence-based guidance.

The microworld that lives in you

From a pod near you

I love a podcast. Episodes of audio goodness are delivered daily or weekly to my MP3 player, ready to keep me company on my long commute. I subscribe to podgrams dealing in current affairs, football, history and comedy.

But the overwhelming amount of disk space is taken up by science. Scientific news, scientific scepticism, scientific ideas, science in culture and scientific history. Even science comedy. Science science science.

Sometimes issues related to pregnancy and childbirth, childhood and parenting crop up, which as a science-minded parent is right up my street. And, I hope, right up other people’s streets too.

Here are some nuggets with which to start.

Ed Yong on BBC Radio 4’s Four Thought | 19 Oct 2011

Science writer Ed Yong describes his fascination with the human ‘microbiome’ – the bloom of microbes that each of us house in and on our body. The cells of bacteria, fungi and other microorganisms actually outnumber the cells of the human host by 10 to 1, and their genes by 100 to 1. Are we humans hosting a microbial community or a superorganism in which human cells are simply partners?

We can’t function as we do without these microbes. They help to digest complex foods like carbohydrates, metabolise drugs and toxins, interact with our immune system, and affect energy balance. The types and numbers of microbes within each of us are different and can depend on diet, environment and behaviour. The microbiome may have even played a part in shaping our evolution. They have such an important role that the microbiome has been called the ‘forgotten organ’ or the ‘second genome’. How, then, would you define what is ‘us’ – is it any cell that contains the same DNA as when we were an embryo, or are the constantly interacting microorganisms that are vital to our survival ‘part of us’.

What’s really interesting, at least from someone interested in child development, is how we gain this microworld. As Ed explains in the audio clip, we develop in the sterile environment of our mother’s womb*. The first gift from our mum is a smattering of microorganisms, but this depends on how we are born. A baby born of a vaginal birth is delivered their birthday presents as they travel through the vaginal canal and slides past (brace yourselves) the mother’s anus. The makeup of bacteria in vagina of pregnant women is actually quite different from that in non-pregnant women. A particular bacterium, usually found in the gut where it helps digest milk, becomes far more abundant in the vagina during pregnancy, which may give the baby a healthy coating as it is born.

Babies born of a caesarian section, however, do not have this close encounter and instead pick up a different spectrum of bugs that more closely resemble the ones found on skin. It can then take a while for the full complement of gut bacteria to establish.

The community expands and becomes more varied as the child interacts with its surroundings. Breast milk has been found to contain up to 600 species of bacteria, which furnish the babies gut and hinder the growth of any harmful nasties. Babies are then ready to take in more complex foods. This in turn fosters a richer microsociety and the mutual relationship continues. Environmental contaminants and toxins can perturbe the microbial community, which has been suggested (though not proven) to contribute to type II diabetes, cardiovascular disease or obesity.

Kerri Smith on Nature Podcast | 23 August 2012

Kerri Smith on the Nature Podcast reports on recent research that shows how antibiotics, at least in mice, can affect the gut bacteria composition and, consequently, the amount of body fat. The antibiotics seem to spur the bacteria into producing more fatty acids, which are converted by the human host into fatty tissue. Listen from 05:45 – 11:35 to hear a discussion with one of the researchers on the study of antibiotics in early life and the possible link to obesity.

And another fascinating potential of our microbiome is discussed by Chris Smith on The Naked Scientists podcast. Listen from 16:30 – 20:55 to hear Dr Marcello Riggio talk about how certain bacteria can promote oral health (good!) but also lead to bad breath or tooth decay (bad). Skip to 21:00 to hear a debate with Prof Gareth Morgan on whether probiotics – beneficial bacteria supplemented in the diet – may help to prevent/treat allergies and gut infections by interacting with the host’s immune system (ends 26:30). This idea is, however, not fully supported by the current evidence: results are variable and inconsistent (see The Cochrane Library reviews on allergies, eczema, colitis and diarrhoea).

Chris Smith on The Naked Scientists | 5th Sep 2011

Click to listen to: The_Naked_Scientists_in_Africa

And, finally, an even more fascinating potential of our microbiome is discussed by Mo Costandi in his Neurophilosophy blog. The bacteria in our guts may have the ability to affect brain development and mood.

For more on the wonder of the microbiome, read Ed Yong’s excellent blog post and Carl Zimmer’s article in the NY Times.

*or, maybe not.

SZZ2C7MMNW2B

Alternative medicine in parenting – part 1 out now!

Just a quick update to flag that the first instalment of a three-part look at the use of complementary and alternative medicine (CAM) in parenting has been posted at The 21st Floor blog. This post focuses on the many CAM therapies advocated in pregnancy and childbirth, from acupuncture and reiki to improve fertility, enzyme therapy and herbs to prevent miscarriage, through to homeopathy and aromatherapy during labour.

I look at the evidence behind the claims and ask whether it’s so wrong if people want to do it. Part 2 will look at the role that some healthcare professionals play in its promotion (and whether this is OK), plus issues around the regulation of its use. Part 3 will focus on “alt med” care for children and the problems this may cause for the population.

As ever, let me know what you think!

In the meantime, here are a couple of comics about homeopathy. Enjoy!

XKCD: Dilution

Saturday Morning Breakfast Cereal

Milking the (cash) cow?

Or, should I feed my one year old cow’s milk or infant formula?

The Skeptical Son is about to hit one year of age, which brings a few landmarks with it. MMR vaccination, standing up (albeit a little precariously), and a move from specialised (breast or infant formula) milk to regular, unmodified cow’s milk.

This latter point seemed pretty uncontroversial. The UK National Health Service and the American Academy of Pediatrics both recommend feeding cow’s milk to a baby beyond 12 months. The NHS explicitly states: “Infant formula, follow-on formula or growing-up milks are not needed once you baby is 12 months old”.

So I was intrigued to see infant milk formula products specifically targeted at the over one year olds, such as Aptamil 1+yr & 2+yrCow & Gate 1-2yr & 2-3yrHipp Organic growing up milk (from 12 months), and SMA 1-3yrs.

A look at the scientific literature, in line with the NHS and AAP guidance, backs up a move to cow’s milk at 12 months. Unmodified cow’s milk is not recommended before this age because it contains high levels of sodium, potassium, phosphorus, and calcium, and lacks vital nutrients, such as iron, vitamin C, and linoleic acid. As a baby’s diet becomes more varied and complex by the age of one, many of the nutrients previously gained from milk (breast or modified cow’s formula) is obtained from food. An infant can, in most cases, safely move to consuming cow’s milk, and it is only if a specific deficiency develops that they will need targeted supplementation.

http://www.flickr.com/photos/jelles/2902422030/

Cow by JelleS [CC-BY-2.0]

The NHS’s health information leaflet, however, says: “It is recommended that all babies aged from six months to 5 years are given a supplement that contains vitamins A, C and D, unless they are drinking 500ml (a pint) of infant formula a day (infant formula has vitamins added to it)”. This then brings us back to enriched infant formula.

The infant formula manufacturers appear obliged to acknowledge that breast milk is recommended for young babies (see disclaimer notice*), consistent with the World Health Organization’s guidance. All of them, though, promote their 1 year+ products as, variously, enriched with iron, vitamins C & D, GOS/FOS prebiotics and omega fatty acids. Advertising claims include milk formula that is “nutritionally superior” to cow’s milk, “has been specially developed to help meet the nutritional needs of toddlers”, and will “encourage your toddler’s natural friendly bacteria to thrive”.

So now I’m a little torn. Anaemia, avitaminosis and lactose intolerance are, evidently, serious conditions that need to be addressed, and products need to exist for these cases. But the marketing doesn’t seem in line with the healthcare advice: without looking into it, I was initially left with the impression that the specialised infant formulas represent the gold standard, containing everything that is needed to support my son’s “amazing development” [© Cow & Gate]. The adverts and packaging don’t suggest these products are for cases where a deficiency has been identified, rather it appears to play to the ‘don’t take any chances’ or ‘be on the safe side’ worry of parents. SMA, for instance, says “it is hard to know if they are getting all of the right nutrients they need at this important time”.

I guess this speaks to a wider problem with nutritional supplements, ‘superfoods’ and enriched dietary products, some of which make all manner of claims about health and well-being (see Andy Lewis’ Quackometer for more ‘Confusopoly of Diet’).

Anyway, now for a quick look at money, something that’s precious to many families. A 900g tub of Aptamil 1+ yr costs £8.49 (Sainsbury’s price). This means that a daily intake of 500ml will cost 79p (83.3g formula). An equivalent daily portion of whole cow’s milk costs 26p. Even adding in a multivitamin supplement works out at an extra 13p a day. Over a week this difference amounts to £2.80; over a year it’s a saving of around £145.

I should emphasise that the post-one year milk formulas seem completely legitimate products to sell and I’m far from claiming a conspiracy, but I explore it here simply to question whether their advertising is a little misleading. Of course, dietary products claiming all sorts of health benefits is not a new or isolated phenomenon, but I worry that the baby market particularly plays on the anxiety of parents that inclines them to prove themselves as perfect guardians.

Maybe I’m being overly cynical in suspecting that the manufacturers are being unreasonably opaque. Perhaps I’m too naïve in wishing that promotion of products that affect ours and our babies’ health was more honest. Would it be regulatory overkill to make infant formula products, in the same way as the breastfeeding disclaimer, carry an objective notice about cow’s milk and the current healthcare advice?

And on that ambivalent note, I shall end.

*The common wording across manufacturers’ websites and the prominent positioning of the statement (it is displayed any time one tries to click through to a product for the first time) suggests this is a statutory requirement. This would be interesting if it is, so any light that anyone can shed on this would be appreciated!

“It must be his teeth”: teething symptom myths

I wrote some time ago about how our little one was teething and the measures we’d taken to alleviate his discomfort. Well, this little chapter is still in full swing, with a mere two teeth erupted so far. But this isn’t a place to write long diary entries detailing my child’s progress; instead, I want to bring some science to light.

I’ve heard a number of physical signs regularly attributed to teething, such as rosy cheeks, diarrhoea, green faeces, fever, gnawing, irritability and drooling to name a few. It seems these beliefs are fairly common, as surveys of parents and health professionals have shown.

It gets interesting, however, when you look at some of the research done in this area. There seems to be some disagreement over which symptoms are actually caused by teeth eruption, and whilst it’s clear that individual babies will display different teething signs, it’s also apparent that some beliefs are not borne out by the evidence.

One of the difficulties is that the onset of teething (6-12 months) often occurs around the same time that babies become particularly susceptible to a variety of infections and upsets. This is mainly due to the decline in immunity imparted by maternal antibodies, as well as changes in behaviours that see infants actively interact with their environment.

There certainly seems a fair amount of evidence that many signs assumed to be caused by teething are actually caused by something else, such as meningitis, bacterial infection and herpes simplex virus infection. As the NHS Clinical Knowledge Summary bluntly puts it: “Teething does not cause children to become systemically unwell”. 

Another problem is our familiar foe: limited experimental design. Studies in this area are rather limited in number, often rely on self-reporting rather than objective measurement, deal with correlations not causations, and many look back at clinical data rather than tracking babies as they develop. These complications may be exacerbated by the fact that many health professionals hold erroneous beliefs too, which influences the data collected.

So what do we know?

Symptoms often misattributed teething:

  • Diarrhoea: This is one of the most common symptoms attributed to teething, but no solid data exist to suggest this is due to teething in the majority of cases. It has been tentatively suggested that slightly looser stools may occur during teething and this could lead to mild nappy rash.
  • Fever: Teething may cause a small rise in body temperature, but a feverish temperature above 38°C is unlikely to be due to teething.
  • Runny nose: The jury’s out on this one, but the reported associations are weak and this symptom is more likely to be a due to a wider problem.
  • Wakefulness: While teething may cause some disruption of sleep, this is probably over-exaggerated by parents, and may be partly down to changing sleep patterns and the formation of attention-seeking habits. I was also told by a midwife that teeth move more during the night, causing greater wakefulness – I initially thought not, as it seems more reasonable that the distress is apparent when there isn’t anything to distract the infant. Any data on this latter point would be gratefully received!
  • Green faeces: This is one I’ve heard a number of times, sometimes with an explanation of a change in the stomach acid balance. I can’t find anything in the literature (but please come forth and proffer!) but, on the face of it, it doesn’t seem to chime with idea that teeth eruption does not cause systemic upset.

 Symptoms more likely to be caused by teething:

  • Drooling: Excessive saliva can form and this may be seen by an infant dribbling more than usual. This isn’t conclusive, though, as salivary glands become active around 2–3 months of age and constant drooling can be expected then.
  • Gnawing: Teething infants may gnaw on cold, hard objects or on their fingers to temporarily help with teething discomfort.
  • Mild irritability: The pain associated with teething, which is mostly associated with an inflammatory response within the gums, might cause grizzliness, disturbed sleep, ear rubbing and a decreased appetite.
  • Rosy cheeks: This is some support in the literature that flushed, red cheeks are associated with teething, although this is not clear-cut.

As I said earlier, different babies will experience different symptoms and it’s worth bearing in mind that no single symptom can definitively ‘diagnose’ teething.

Many of these beliefs appear to have some root in history as far back as Hippocrates in the 4th century, when teething was thought to be a deadly disease (“dentition difficilis”, Latin for ‘difficult teeth’). Teeth eruption, it was believed, caused a disturbance in the infant’s nervous system, leading to severe systemic upset. This was, again, most probably due to coincidental timing of onset of teeth eruption and an increased likelihood of serious infection, which in those days often led to infant death. Worse still, many of the treatments used for teething right up until the 19th century were actually toxic, such as opiates, lead, mercury salts, bromide and salt.

So while some studies have suggested that teeth eruption is associated with certain physical symptoms, none has really been able to establish causal relationships, and others have found no associations at all. It may be that a diagnosis of teething can relieve parents’ anxieties about an upset infant. Understanding true causal factors, however, is important to prevent misdiagnosis – attributing symptoms to teething could miss more serious conditions that require immediate medical attention.

P.S. I was hampered in my access to a lot of the research in this area, and so if I’ve missed anything then please let me know. A good argument to support Open Access publishing!

Is breastfeeding all it’s cracked up to be?

Zoe Williams wrote an intriguing article in The Guardian that challenged some widely held assumptions and beliefs about the benefits of breastfeeding (‘The backlash against breastfeeding’). It did, as you might imagine, generate strong reactions from those who vehemently espouse that “breast is best”. It was written on the back of a recent front cover of Time magazine that caused an even greater furore (‘Are you mom enough’), which championed a form of ‘attachment parenting’ that encouraged breastfeeding until the child is well over one year old.

I did feel that Zoe Williams’ article raised some interesting points, some of which I wanted to address here.

But I also had the strong suspicion that the claims made for [breastfeeding’s] benefits – the higher IQ, the protection against obesity, the superior bonding, the warding off of disease both now and for ever, both for baby and for mother – were mostly bogus. A lot of the reasoning seemed syllogistic (babies born into low-income families end up fatter; low-income mothers breastfeed less than high-income mothers; therefore breastfeeding prevents obesity) or frankly lame.

This relates to the concept I’ve written about before, that correlation does not imply causation. As she quotes Joan B Wolf later in the article: “Breastfeeding cannot be distinguished from the decision to breastfeed, which could represent a more comprehensive commitment to healthy living.”  

While this is true, that is not to say that the researchers who conduct these types of observational studies are not aware of this limitation. It is hard to do interventionist, controlled studies, as you would do in a lab or in randomised controlled trials to test a new medicine. Imagine randomly assigning new mothers to one of two groups – breastfeeding or formula-feeding – and getting them to stick to this regimen so that you can measure the outcomes of the children. Not likely, which is why such interventionist studies have been limited (1 & 2).

So researchers work with the tools available to them. They try to include appropriate comparator groups and make statistical adjustments to account for potential confounding variables. Not perfect by any stretch, but the best available methods.

I knew a lot of mothers who formula fed; they didn’t seem to love their babies less.

Ignoring the submission to anecdote, which is a mortal sin to evidence-based thinkers, a more worthwhile point to address is an argument I’ve often heard that goes approximately: “Well, they say breastfeeding is best, but I formula-fed and my child turned out alright”.

There are two key flaws in this reasoning. One is that by advocating breastfeeding, it is implying that formula-feeding is bad. No. It’s just there’s less chance that any outcomes associated with breastfeeding will also be seen with formula-feeding. The second misconception is that there’s a complete separation, or dichotomy, between the two groups. But here we’re comparing averages of large study groups – there will be huge amounts of variability around the averages and a lot of overlap, and only the right statistical analyses can reveal any true differences.

Put simply, there will be mothers of formula-fed babies who form strong attachments (to carry on the example in the article) and mothers of breastfed babies who do not.

By analogy, there will be some people that do all the ‘right’ things – not smoke, eat healthily, exercise, apply sun cream – who will get cancer and there will those who smoke 40-a-day and drink to excess who do not. It doesn’t disprove the link, it’s all about stacking the odds in your favour.

(I should clarify that the evidence I’ve seen for superior bonding associated with breastfeeding is somewhat weak, but I referred to it here to address a more general point about the common use anecdotal evidence).

This struck me as a bizarre place to have arrived at; where even to talk about the evidence behind the benefits of one type of infant feeding over another is heretical.

Absolutely correct. We should constantly gather and scrutinise data, and if strong enough evidence emerges that contradicts our prior assertions, then we should be prepared to change our minds. I applaud the fact that this article was written, even if there are bits I wouldn’t necessarily or wholeheartedly go along with, as we should always be ‘talking about the evidence’.

The questioning of the orthodoxy is taken as a direct attack on babies.

[Charlotte Faircloth, sociologist]: “… Everything has got very heated, and very moralised. How you feed your kids is no longer a personal decision. There’s this idea that you can breastfeed your way out of poverty, or if you don’t breastfeed your kid’s going to be fat or have a low IQ…” She pauses. “It’s all got a bit out of hand.”

Williams is right that some breastfeeding advocates are evangelical and overly ideological about breast milk, to the point that some mothers feel over-bearing pressure to breastfeed. As Charlotte Fairclough is quoted, it’s a personal decision. Fairclough also touches on my earlier point that there’s no binary distinction in the outcomes of children who are breastfed and those who are not – breastfeeding doesn’t determine the outcome but may make it more probable (and, if it does, it will certainly still only be one factor amongst many).

Williams then quotes French feminist Elisabeth Badinter:

“when it’s recommended that you breastfeed your child for one year – six months exclusively, with nothing else, day and night, on demand – there are obviously consequences for a couple.”

“There are women for whom breastfeeding is a true pleasure. It’s very good for them and it’s very good for the baby. But to breastfeed a baby if the mother herself doesn’t like it? It’s a catastrophe. The decision to breastfeed is an intimate and private decision. No one should be able to interfere.”

In my mind, this touches on something I have written about before – that to lay down a hard-and-fast prescription for parents to follow is not always straightforward or productive. A more nuanced approach is often required that takes into account the familial circumstances and considers the parents’ well-being as well. It would be no good hectoring parents to follow a particular path, if it leads to a significant worsening of their own physical or mental health, especially if the knock-on effect is a deterioration in family relationships.

It seems highly unlikely that this would allow people to be good parents nor provide a decent environment for the child (a brief look at the scientific literature suggests this assumption isn’t entirely unreasonable, e.g. thisthis and this). It also risks attaching blame to a parent for any perceived character flaw in their child, and guilt-tripping parents in this way seems a counter-productive approach.

The research about ear infections, respiratory disease and diabetes is very mixed. Neither fussiness around new foods nor constipation are classic or very salient markers of good health. The obesity studies are debatable. The weight loss of breastfeeding mothers is taken from a WHO report, based on two interventionist studies in Honduras. It’s nothing like that straightforward: it does use 500 calories a day, but if your appetite increases at the same time, it is amazing how quickly and easily you can pop 500 calories into your mouth. Meanwhile, Wolf points out, no study on maternal cancer has “distinguished the effects of breastfeeding from the behaviour of women who breastfeed”

Again, I agree, it’s not straightforward! But I would, perhaps, strike a more positive tone.

The studies aren’t perfect (Williams also quotes the American Academy of Paediatrics: ‘There are a lot of methodological problems’), but that’s no reason to just give up on evidence altogether. The best available evidence, as far as I can see, is saying that breastfeeding is likely to bring a range of benefits to the child, and possibly some to the mother. A Cochrane Review from 2009 includes many citations that support various benefits of breastfeeding, as well as a discussion of some of the uncertainties.

I also agree that the weight loss data must be taken in context, such as whether you are dealing with developed or developing countries, and some effects, such as iron status, can be achieved through supplementation. So, in some instances, there’s no need to be over-zealous about breastfeeding, as long as adequate healthcare advice is in place.

“The notion of risk [has been] transformed from a dichotomy to a continuum.” It’s no longer a case of “safe” versus “dangerous”; rather, everything carries some risk and you announce your fitness as a parent to the world by interpreting hazards in the most credulous, fervent way. The onus isn’t on the researcher to prove the point any more – the onus is on the parent, or parent-to-be, to prove that they’ll believe the researcher.

I’m not sure this is true and seems an over-generalisation. There’s a huge variety in parental attitudes and some are incredibly questioning, and whether and how this has changed in recent years is uncertain without any data. I think it misrepresents the role of a researcher, too – that the onus is on them to ‘prove a point’. Scientists don’t (or shouldn’t) undertake work to prove already held beliefs, rather they formulate hypotheses and design experiments to support or reject those theories.

There are lots of other points in and around the ones I’ve highlighted, a lot of which veer from my intention to address evidence-based decisions, but I do encourage you to read the whole article for some interesting discussion of feminism and social policy.

I’ll summarise by saying that I would still state that breastfeeding can potentially bring a range of benefits over formula-feeding, because that is where the balance of scientific evidence is, with little or no contrary evidence to dissuade me yet. And this should be reflected in the healthcare advice that is provided. I absolutely agree, though, that foisting this decision on mothers is, at best, unnecessary and, at worst, damaging. Healthcare advice must take context into account.

On a more general point, I welcome any sensible, critical look at the evidence behind claims, as Zoe Williams has done. It’s certainly made me re-evaluate – and in some instances, such as in the link to lowered risk of maternal breast cancer, made me temper – my own standpoint on the benefits of breastfeeding.

A final point, though. It was disappointing that an article that relied so heavily on rejecting or challenging some of the evidence that is used to promote the “breast is best” standpoint, did not once link to any primary research. A few quotes here and there from, no doubt, serious academics, and a link to a book, but nothing that could point the reader to the original research studies.

It is perennial complaint that evidence-based advocates level at popular journalists, so I don’t want to single out this author for special criticism. But it is something that could do with a cultural shift and, perhaps, mainstream commentators will start to follow the examples of their science colleagues.

———————-

Hat-tip to Mum-in-law, Jenny, for The Guardian article.