Fat, Fate, and Disease : Why we are losing the war against obesity and chronic disease (36 page)

In this book we are arguing for action—focused on mothers and children—to reduce the risks of non-communicable disease in large sections of many populations. Our arguments are based on a growing base of knowledge and evidence. So what does the ‘post-normal’ approach tell us? Are the risks of acting on incomplete or flawed evidence too great? If we are wrong, we will have promoted women’s and girls’ empowerment and women’s and children’s health, and this can only have positive effects on national and personal development. The costs of such interventions are not great. It is difficult to see
any
risks in taking this course of action. On the other hand, if we accept the argument that the focus of intervention should remain on the adult, and do nothing to promote a healthy start to life until we have substantially more information, we will place the next generation at greater risk of chronic disease and potentially incur an enormous cost. We rest our case. With what we now know, it is clear that the balance of arguments weighs heavily in favour of action. We can put it off no longer.

Ignaz Semmelweis was a young physician working in the 1840s in a charity maternity hospital serving the under-privileged women of Vienna. But ‘serving’ might be the wrong word, for this hospital was actually a place of death. Alarmingly, one in ten women admitted to a particular ward to give birth in the hospital would die. The cause was a severe fever, starting soon after childbirth, called puerperal fever—‘puerperal’ being the Latin word for childbirth. It is now known to be a form of blood poisoning due to bacteria entering wounds and tears in the vagina and cervix during delivery. But in the mid 19th century this mechanism was still to be discovered.

It was general knowledge in Vienna that being admitted to this ward was a death sentence, and women begged to be sent to have their babies in another ward at the same hospital where, strangely, the risk of death was much lower. Some women said that they
would rather deliver on the street than in the deadly ward—the risk of death from delivering on the street was indeed less.

Semmelweis, at 29, was at an early stage in his career and his superiors would maintain that he still had much to learn. But he could not ignore this problem. He became obsessed with finding out why this one ward had such a high rate of maternal death while another was much safer. There was nothing obvious: the two wards used the same approaches to managing the childbirth and the mothers after birth; they used the same equipment and protocols. He looked into every possible detail of what could explain the horrific difference in outcomes. One ward was more crowded than the other, but the overcrowded ward was actually the safer one, because that was where women preferred to be. The only other difference which he could see was that the first ward was used to train medical students and the second ward to train midwifes, but that seemed trivial and irrelevant. Surely that alone could not explain the difference …

Semmelweis pondered and pondered. Then in 1847 a medical colleague who was a close friend died from a fever, after being accidentally pricked by a student’s scalpel while they were jointly performing a post-mortem. The post-mortem findings on his friend looked to Semmelweis very similar to those of the dead women from the less safe delivery ward. Although the ‘germ theory’ of disease, which would later explain the transmission of illness from one person to another, was not yet known, Semmelweis wondered if some toxic particles from the dead body being examined had been passed on by the scalpel to the body of his friend, leading to his death. If so, could the same particles from the corpses be transferred from doctors’ and students’ hands to women in labour or after delivery, and cause their puerperal fever?

Suddenly, and sickeningly, Semmelweis realized the possible significance of this idea. Medical students did post-mortems as part of their training; midwifery students did not. Suppose the students went straight from the post-mortem room to the maternity
ward—if their hands carried the dangerous particles, perhaps they could pass these on to the women in labour and give them blood poisoning. Was the problem due to nothing more complicated than the medical students having dirtier hands than the midwifery students? It was a testable hypothesis: Semmelweis insisted that medical students and doctors on his ward washed their hands in a chlorine solution after they did a post-mortem and before examining a woman on the ward. And their instruments were also to be washed. He chose chlorine as his washing solution because it got rid of the smell of the rotten flesh from the post-mortem and he guessed it might therefore be destroying the unknown deadly particles—he was not to know that chlorine is a powerful disinfectant, the active ingredient of household bleach today.

Within six months of introducing this policy onto the ward where the medical students trained, the mortality of women dropped dramatically—it even fell below that of the ward where the midwives trained. In some months no women at all died on the ward. It was a dramatic change and it was clear to Semmelweis that hand washing in chlorine solved the problem. Surely this evidence would be accepted by everyone? He started to publicize the idea. He wrote letters to other hospitals, describing his life-saving results, and they were soon published in the major medical journals of that time. But were his ideas of hand and instrument washing adopted? Not really, not in many places.

Instead Semmelweis came under intense attack from his colleagues and superiors. His theory did not fit with the orthodox models of disease favoured at that time—that illness results from changes in the balance of ‘humours’ in the body. He could offer no sensible scientific explanation for what he had observed—only repeat that he had seen the results to be dramatic. The principle that direct observation should outweigh prejudice and dogma was not yet well accepted in science—maybe it still isn’t (think of climate change denial). Other experts thought that there was nothing original in what he was
saying—another stock criticism of a new idea. Anyway, it was insulting to the medical profession to suggest that they should have to wash their hands—how could such gentlemen be unclean?

Then politics intervened, for Vienna was very unstable at that time. Semmelweis was forced out of his job and he moved to Budapest. Undeterred, he again introduced his chlorine hand washing rule into the hospital—again with the same dramatic results, and again the local medical establishment ignored him and railed against adoption of the procedure. Finally the pressure took its toll, and Semmelweis was admitted to a mental hospital. He died soon after admission, at the age of 47—ironically from fever which was probably caused by an infection following a beating by the hospital orderlies.

It was only some 20 years later—after the discovery of the role of germs in causing disease by Louis Pasteur in Paris—that the importance of Semmelweis’ brilliant insight would be recognized. He had produced a paradigm shift in medical practice that has undeniably saved millions of lives. It is a tragedy that he did not live to witness this shift.

The story of Semmelweis has some parallels with the one we have told in this book. When there is a problem, and the strategy to solve it is not working, we need to look at the situation afresh, at what might really be going on, and get beyond established dogmas. We need to look at the empirical data and observations, rather than basing our actions on belief and fashion. We have to take our blinkers off. The answer may then be surprisingly obvious.

There are many other examples in medical history where cutting-edge science has been ignored or considered implausible—sometimes at great cost to human life. Earlier we described how Mont Liggins discovered in 1972 that steroid hormones given to
mothers in premature labour prevented their babies dying from lung disease. But it took another 20 years for the USA to adopt steroid therapy as standard and all sorts of excuses were used to ignore Liggins’ data. Might the acceptance have been faster if he had made the discovery in the USA rather than in New Zealand? We don’t know. But all too often, in medicine as in other areas of life, there are vested interests that consciously or unconsciously influence the strategies adopted.

More recently we have seen the denial of the role that the human immunodeficiency virus plays in the origin of AIDS, which effectively prevented the use of antiretroviral drugs in South Africa. Many lives were lost because Thabo Mbeki’s government refused to accept the overwhelming scientific evidence—albeit from research in developed countries—that a virus was involved. Diverting arguments were used and ineffective remedies were promoted instead. In other places we have seen authoritative claims that condoms do not help stop the spread of HIV-AIDS, despite the overwhelming evidence that they do, simply because the use of condoms does not fit with the values of one particular religion—and at what cost? It can be very difficult for new scientific discoveries to overcome preconceptions and dogmas when the evidence conflicts with values, be those values professional, political, cultural, or economic.

Large scientific, medical, pharmaceutical, and public health enterprises have been built on the presumption that the current paradigms of how to manage the burden of obesity, diabetes, and cardiovascular disease
must
be right. Cynically we might say that private sector organizations, such as the pharmaceutical or the weight loss industries, have invested far too much in this strategy to allow new ideas to change it. But apart from the money, there is considerable investment in ego, reputation, and the careers of many scientists, doctors, public health practitioners, and agencies, and this is not helping. There are many reasons why it may be easier to ignore the fact that we are losing the war.

But the facts are undeniable: the incidence of obesity and the number of deaths from non-communicable disease are continuing to rise in the high-income countries, although the mix is changing because of the major beneficial effect of a reduction in smoking. And we have seen how the incidence of diabetes and cardiovascular disease is exploding in developing societies. Most of the strategies we are now using in the West, other than those against smoking, are clearly not working—can we expect them to work more effectively in developing countries? We are sceptical.

The life-saving achievement of Semmelweis resulted from his developing a strategy based on evidence rather than dogma. His evidence was not sufficient to change the minds of his colleagues, at least during his lifetime, partly because it inevitably attributed a certain amount of ‘blame’ to a causative agent—the medical students who did not wash their hands. His medical colleagues had other and very deeply rooted ideas about the causation and the blame—unbalanced ‘humours’ in the patient herself. We see some parallels between this story and the one we have told in this book. Are we challenging dogmas about where the blame lies for diabetes and cardiovascular disease?

Most of the strategies to address the epidemic of obesity, diabetes, and cardiovascular disease in developed countries have been based on the assumption that the primary problem is behavioural—deal with smoking, persuade adults to consume fewer calories, particularly less fat and salt, and to exercise more, and all will be well. This lifestyle-focused approach also fits in with Western libertarian philosophies which seek to maintain the individual’s liberty to choose, and reduces the onus on the State to intervene. But unlike smoking, people have to eat, and there is an argument that the State has no business to interfere in our lives in this respect. Indeed many
governments have found to their political cost that there is an electoral price to pay for over-interference in individual choice.

Besides, the simplistic view is that, unlike smoking, there is no ‘passive’ obesity, and so the State does not have to intervene to protect the innocent third party. But this is wrong: there are indeed many ways in which obesity and chronic disease can be transmitted passively from one person to another—both by social transmission and biologically across the generations.

It has become clear that it is intellectually dishonest to base the global approach to non-communicable disease prevention on the assumption that voluntary lifestyle choices are the primary cause of the problem. We have seen the many ways in which cultural, social, and physiological factors conspire to place most individuals in a situation where it is almost inevitable that they will become obese or develop diabetes and cardiovascular disease. The key issue is that we are all exposed to lifestyles that put us at risk and for many of us our capacity to make the changes essential for safety are limited or impossible because of what has happened to us earlier in the life-course. Where the cultural and social factors prevail, they are not easy to overcome—partly because they too can become hard-wired and irreversible through early life. The biological arguments are compelling.

Having said this, we would not want the reader to come away with the idea that there is no health value in eating better and exercising regularly (and certainly smoking should be actively discouraged). Far from it, for where this can be achieved it will have real benefit—anything that improves the match between our biology and our lifestyle promotes health and reduces the risk of disease. But these strategies largely apply to Western countries, and at best can only ameliorate the problem. Transferring them to the emerging countries will be difficult—except in the case of smoking reduction where some developing countries are starting to make real gains. But it is not realistic to imagine that we can effectively reduce the incidence
of diabetes and heart disease simply through lifestyle improvement in emerging countries using similar strategies to those that we have been using in the West. Far deeper issues are involved that need to be addressed.

Even if these behaviour changes were effective, they would have limited impact. Most people in the least developed world do not place as much emphasis on future events as those in the West. Surveys in developing countries have shown that, while all parents want the best for their children, people in difficult circumstances are also realists—what happens today and tomorrow is far more important than what
might
happen in 20 years’ time. This is essentially the point that Dan Nettle was making in his evolutionary argument, that people in poor circumstances live their lives at a faster pace. Effective lifestyle intervention will also be of limited effect until there is more equitable economic and social development, both within and across societies.