Friday, 19 August 2011

Dairy and casein: some positive PR

Remember the campaign 'milk has gotta lotta bottle'?

It was a bit of a daft advert but I doubt many people who saw it forgot the tune and the public relations (PR) message: milk = good, so drink lots of it. The advert was made on behalf of the UK Milk Marketing Board who perhaps had an interest in making sure that we all bought as much milk as possible to be healthy (and also support our dairy market). As per a previous post, through my childhood, I had a slightly different opinion of school milk.

Milk, and its protein casein, has played and continues to be play, quite a large role in my professional life alongside its dietary partner, gluten. To save any confusion, I will state for the record that I hold no personal grudge or ill-will against these ubiquitous compounds despite the various suggestions that they may play some role, either directly or peripherally in some cases of autism and perhaps a few other conditions outside of their classical links. For the majority of people milk (and bread) are staple foods and provide countless nutritional benefits particularly for those who are economically less fortunate than ourselves.

So as to demonstrate my impartiality in relation to milk and casein, I first offer a few lines of evidence suggesting some positive effects linked to the ingestion of said foodstuff outside of the quite well known calcium link. There is this fairly comprehensive meta-analysis demonstrating a possible protective effect of milk and dairy products on the risk of developing colorectal cancer. Replacing carbohydrates with a milk protein supplement might also lower blood pressure according to this study; although I do perhaps question what might be having the effect, given the carb-health associations which seem to be emerging daily. Milk has recently also been suggested to be better at hydrating children than water (despite who funded the study). This study also suggested that a certain type of fermented goats milk might serve as an alternative to all those ever-so modern probiotic drinks which seem to be all the rage, with its positive mucosal effects.

The paper on fermented goats milk is an interesting one. Interesting because it asks a few questions, not least, are all dairy products the same? It is well known that different mammals, even different animals of the same species produce different types of milk structurally. This is none the more evident than when looking at the recent A1 vs. A2 milk debate (I will leave this for a future post). Even based on the same core product, the way that milk is processed might also affect its various properties. A recent large epidemiological study has been completed and published based in Sweden trying to ascertain whether milk consumption was in any way related to risk of cardiovascular disease (CVD). The abstract is here. The main findings were that when dairy products were divided up into specific categories (fermented dairy products like yoghurt vs. regular, non-fermented milk), higher intake of fermented dairy products was associated with a lower risk of CVD. This might suggest that not all dairy products are the same and their impact on health might similarly vary according to what type and what form of dairy is consumed.

Similar work on fermented milk products such as kefir has also provided some interesting data. This paper for example suggested that kefir might aid the so-called leaky gut, at least in mice, which has been implicated in quite a few conditions including autism. Kefir is an interesting product in that its effects could be due to lots of things. It could be due to the various bacteria present (traditionally using sheep's intestinal flora, don't ask me how); it could be due to the various yeasts present, it could be due to the fermentation of lactose, one reason why kefir has been suggested as an alternative for lactose intolerant individuals. This last effect might be particularly relevant in light of the fairly-recent Harvard findings.

We are still very much at the early stage of dietary intervention research for conditions like autism, despite the fact that it has taken almost 30 years for research to get this far. I would like to think that as our scientific interest and understanding increases in this area (accompanied by a few more research pounds and dollars), more investigations can be undertaken to determine exactly how dairy (and gluten) specifically affects some cases of autism. Whether also a dairy-free diet should automatically mean a total dairy-free diet for some or all is another question posed.

To finish, was it something about the 1980s and milk- and wheat-based products which lead to such annoying adverts being aired?