thu 11/08/2022

Horizon: The Nine Months That Made You, BBC Two | reviews, news & interviews

Horizon: The Nine Months That Made You, BBC Two

Horizon: The Nine Months That Made You, BBC Two

We're not what we eat, but what our mothers ate when we were in the womb

This was the sort of science programme that an interested non-science person like me finds immensely irritating. It began with a series of statements which were, in fact, meaningless overstatements. Not only this, but these overblown statements tripped each other up: “Scientists think they’ve discovered the secrets of a healthy, happy, long life – for all of us” (don’t you just hate this kind of teasing nonsense that treats us all either like fools or Daily Mail readers?) was followed by, “This is one man’s struggle to unravel our destiny.” So what was it to be? A dramatic narrative about one man’s “struggle” or about the consensus of “the scientific community”? Confusion. And we weren’t even two minutes in.

But then we got a confident assertion – one that seemed to come neither from this one "maverick" alone, nor solely from the fledging investigations of a research team, but as a statement of fact. We were told that as soon as people are born their physical and mental abilities, how long they’ll live, and how happily, are all determined. Which, of course, begs a question: all determined by what? And since all of these things – happiness, cognitive ability, physical health – are all quite singular, then "determined" seemed a pretty big, all-encompassing word.

As it happens, this wasn’t another programme on genetics, because genes didn’t even get a look in until we were almost halfway through, and then they weren’t even dwelt on very much. Indeed, genes didn’t even make it as a contributing factor of anything at all, for this was in fact a programme, primarily, about birth weight and future health outcomes. More specifically it was actually about the risk of developing diabetes and heart disease. So why all the guff at the beginning? I know science programmes have to tell a story in a way that grabs the viewer’s attention, but surely they need to be clear and precise, too?

The research was interesting because it suggested that low birth weight is far more important to health outcomes in later life than lifestyle factors. So going to the gym and eating lots of fruits and veg and keeping your weight down is not going to make much difference to the risk of developing Type 2 diabetes as an adult. Contrary to current thinking in this area, it’s not what we eat, but what our mothers ate when we were in the womb that makes the crucial difference. (And, apparently, it’s not our genes.)

Professor David Barker’s research had initially found him studying birth records in Hertfordshire, but then his investigations took him to India, to Pune, where doctors find themselves in the grip of a diabetes epidemic among populations that are active, appear to eat well and are not obese. In fact, they are pretty thin. Barker’s hypothesis – that low birth weight correlates with diabetes – had undergone some tests.

In one hospital 200 babies had been followed to adulthood to see whether they displayed early signs of insulin resistance. These babies were now 21 and a link between low birth weight, insulin resistance and rising blood glucose in later life was established. What was going on? As we shortly found out, these thin adults were actually “fat”, that is, they had a low Body Mass Index but a high percentage of body fat, and this was all linked to poor pre-natal nutrition.

But wasn’t there some genetic predisposition playing in the background to all this? I mean, you’d think that taking a few small communities in one area of India might expose some familial links. But then off we went to look at the 1944 Dutch famine, and found low birth weight was linked to not only diabetes, high blood pressure, heart disease and raised cholesterol but to breast cancer. But here you wanted to pause again: the war-time famine in Holland was a situation so extreme that one wondered if it could explain all, most or just some cases of these diseases. What about doing a study in Bradford, apparently the fattest city in the UK? And what if your mother had a family history of Type 2 diabetes but ate really well in pregnancy? What was your risk then? 

And then we went further off-piste to talk about other studies to do with personality and stuff like levels of testosterone in the womb. We were told that girls who had too much of it favoured toy guns and girls who didn’t favoured dolls, just like some species of monkeys. And then we looked at scan of brains to look at... what? I can’t even remember. Needless to say, all of this skimmy stuff muddied the waters a bit, but it was a programme determined to say that everything about us was already determined in the womb. And that it was little to do with our genes. It left a lot of dangling questions. This, you might say, is what science does, but this programme did it in a way that suggested it had all the answers already wrapped up. Irritating.

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