Fat, Fate, and Disease : Why we are losing the war against obesity and chronic disease (30 page)

And while public health specialists have paid attention to the importance of maternal and child health, the contributions of early life to chronic disease development remain poorly incorporated into their thinking. To some extent the reasons for this narrow view are historical and to some extent they are practical. Throughout its history public health has achieved notable successes, for example in the reduction of infectious illness through better sanitation and vaccination, and the increasingly impressive effects of anti-smoking campaigns especially when these were linked to sales restrictions and excise taxes. These are areas where the division between health and disease is clear and where an agent causing the disease—a bacterium or virus or the tar in smoke, for example—is known. But as we have seen when it comes to obesity, diabetes, and cardiovascular disease the situation is much more complex. The concept of a single causative agent does not work—we cannot live without food and in any event there is enormous variation in how we respond to what we eat. We have spent much of this book explaining why the solution is not as simple as just promoting exercise and diets.

A discipline closely related to public health is that of epidemiology, which is the study of patterns of disease in populations. Large data sets are collected to do this, and cohorts of subjects may be studied for a number of years to look for correlations and associations. For example, it was from such associations that the link between smoking and lung cancer was shown. There is an enormous community of epidemiologists studying cardiovascular disease, diabetes, and obesity, but most of them are researching only adult populations. In such studies it is easy to look at current exposures such as patterns of
eating and exercise, but it is virtually impossible to look backwards into the early lives of the subjects. An inevitable bias of such studies is a focus on the importance of what is happening now and an underestimation of or failure to recognize the importance of what happened much earlier in life—where data are not available.

One answer is to study birth cohorts, that is to document babies from birth and see how they grow up, and it was from these data that researchers such as David Barker made the important connection between early life and later disease risk. Such studies are expensive and it takes a long time for the results to become clear. Even designing them is not easy, because it requires being very open-minded. It is difficult or impossible to go back and collect data, let’s say on some aspect of pregnancy, at a later date. But now the results of just such studies are emerging in the UK, the USA, Thailand, India, Singapore, New Zealand, and the Scandinavian countries. Very often these studies have been championed by enthusiasts, and often they were not funded by government sources—they were viewed as too speculative, too risky, and too open-ended. Once we start to take a life-course approach to medical research, where will it end? Where indeed.

Drug companies also have a vested interest in focusing on the adult rather than the child, for that is where the greater proportion of income comes from. It is perhaps too cynical to argue that the pharmaceutical industry will not be interested in developing new drugs to prevent chronic disease when they can make a fortune from providing drugs to treat such disease for millions of people for years or decades of their lives. However, if a drug could be developed which would prevent such disease with certainty, following a short course of administration rather akin to an immunization against an infectious disease, then there would be an enormous market for it. But then safety would be a major concern in such an approach; the costs of ensuring that a new drug meets regulatory standards would be high and would take much longer than the
patent life of the drug concerned. New regulatory approaches are needed if we are to pursue this route.

In any event the range of drugs licensed for use in children is quite rightly narrower than for adults, and narrower still for pregnant women. We have not forgotten the lesson of thalidomide. So even though in animal studies it is possible to reverse the effects of a poor start to life by drug therapy in the newborn, in reality we are far from prescribing such therapy to children. But perhaps here we are being too simplistic in thinking that a drug will provide the answer to preventing metabolic and cardiovascular disease. Aren’t we falling into the trap of looking for the magic bullet again?

A more subtle approach would be to develop a nutritional strategy. After all, unbalanced nutrition across the life-course is in part the cause of the problem, so maybe nutrition can correct the problem if it is introduced early enough. The food companies are starting to see the opportunities here, for example, to improve nutrition of mothers during breastfeeding and to use epigenetic information to improve the composition of infant formula. Here is an example where the food industry can be encouraged to make a difference. It may have little choice in the matter, too, for food is increasingly being recognized as something which has dramatic effects on our lives, and in turn, the regulatory authorities may look to epigenetic tools to assess the biological effects of many food components.

No longer can the multinational food companies stand aloof, and take the view that they will provide a range of foods and nutrients—whether healthy or not—and leave it to individuals to choose what they want. Governments and regulatory bodies such as food standards agencies are now beginning to insist that considerably more information is provided to the public about the content of the foods that they buy, especially packaged and processed foods. Most of us simply don’t have the knowledge or the training to make judgements on what to buy and what to avoid.

Increasingly food companies want to address this challenge by developing products which they claim will specifically promote health or reduce the risk of disease. Labelling a tub of margarine as being good for the health of your heart is clearly a great marketing tactic. But how do we know if the claim is true? Indeed one of us found in his local supermarket a packaged food labelled ‘enriched with omega-6 fatty acids, proven to improve your heart health’. Really?

Falteringly, regulatory authorities are getting into the act, demanding that the food companies provide evidence for such claims. There is a lot of work to do here for both regulators and companies, and there are differences as to how regulators approach this matter. The foods produced by the global multinational companies may be regulated, but much of the so-called health food supplement industry is not. Standards need to be established and understood. The companies that invest in research-based validation want to be able to distinguish themselves from the multitude of new-age companies claiming health benefits from various food extracts. And the nature of a clinical trial for a drug used to treat a disease is very different from what is needed to develop an argument that a food maintains or improves health. Trials that have disease as their endpoint are just not realistic—they would take 30 years or more to conduct.

Despite all this, some leading companies are willing to take on the challenge and are now engaged in long-term collaborative research with basic and clinical scientists to find firm scientific evidence to support health benefit claims for certain foods. It is easy to see such initiatives as simply a cynical attempt by multinational companies to increase their market share. This, of course, is true to a degree, as the private sector does not normally invest money in something unless it will confer financial advantage in the long term. But there is really no alternative unless we are willing to pay much higher taxes to enable ‘independent’ organizations, such as government departments or agencies, to undertake the research—and the plain fact is
that we are not. We have to keep an eye on the profit motive in the food industry, to make sure that it does not get totally out of control, but surely we all want more clearly labelled and healthier foods to be provided in the same way that we want safer cars, soaps and washing powders that do not cause dermatitis, dyes that are not carcinogenic, and so on. The role of the regulatory bodies in protecting the public is clear and, particularly with foods, the standards must be very high.

As this chapter has demonstrated, there has been a big shift in our understanding of development. Genes and lifestyle alone do not explain what makes us what we are. Development plays a critical role in many ways. Our biology is changed through epigenetics; our behaviour is changed by learning and experience. The more we look at the obesity and chronic disease epidemic the more we see that we have to go beyond ‘gluttony and sloth’, beyond our current lifestyle and behaviour, and look back to the start of our lives if we are to understand why some of us are more vulnerable to chronic disease than others. And the more we look, the more we understand. There is an enormous change in our thinking under way. Investment in validated approaches early in our lives will likely pay enormous dividends in terms of the pattern of disease in future years.

The problem of non-communicable disease is getting worse—nowhere in the world is its incidence falling—it is rising inexorably in the West and alarmingly quickly in developing countries such as those in sub-Saharan Africa. To imagine that we can simply take failing strategies from Western countries and apply them successfully in the developing world is manifestly wrong. Indeed we need to be certain that what is offered in developing countries is culturally sensitive and appropriate to the populations—they must drive their own agendas assisted by new scientific insights. Further, the growing concern in the West about the developing world cannot be used as an excuse simply for the West to market medicines and healthcare services to countries which cannot afford them. We must be
sensitive to the economic development agenda that is necessary in such countries, and recognize that a more holistic approach involving areas such as women’s empowerment and education, as well as a focus on the beginning of life, will have not only long-term effects on the pattern of disease but also many other benefits.

Such a holistic approach will benefit developed societies too. We know that there is unlikely to be a magic bullet for dealing with the problems of obesity and chronic disease. The reality is that we face the challenge of applying complex interventions to bring about changes at many levels in society—education, nutrition, the food industry, the built environment of home and workplace, etc. We have to learn how to develop for healthy life in a complex world and one which is changing very rapidly. Focusing on our adult or even our adolescent lives alone will not provide the solution—it will come too late for most of us.

There are many factors which create barriers to an effective strategy for winning the war on obesity, diabetes, and cardiovascular disease. We have seen that merely focusing on adult lifestyle will inevitably have rather disappointing effects when looked at in terms of a whole population. For some it will help a lot but for many it will only slow their progress down the path to illness. We have seen that there is enormous variation in how some people get fat and suffer chronic disease in the modern world while others appear more resistant. We have seen that there is enormous cultural and societal variation in attitudes to food and why healthy lifestyles and the motivation to stay healthy are, for many, hard to sustain. We have learnt that development matters in many ways—both through changes in our biological make-up and through what we learn when we are young. We have seen that our biology is influenced for life by the behaviour of our parents and possibly our grandparents, by our life as an embryo and as a fetus, and then by how we are fed in the first few crucial years of life.

There is still a lot to learn but we may have the tools now to answer some of the critical questions, such as: what is the best way of feeding babies from the time they are conceived? We have reviewed the exciting research of the last few years which has shown how important epigenetic and developmental processes are in explaining why we get fat and why some of us get chronic disease. Surely we can now use that information to start doing something rather than just talking about the problem? Indeed it could be argued that with the knowledge we have now it would be unethical to wait any longer. But as we have seen, there is already a large investment in the current approach which focuses on the adult, and the blinkers are still firmly in place. While it would seem obvious to look elsewhere when the current strategy is failing, few have been ready to admit that the war will be lost if we do not adopt some innovative and new approach. We have enough knowledge and it is time to do so. So where do we start?

An analogy with global warming may be apposite. Climate change is another kind of environmental challenge affecting the human condition that is also to a large extent of our own making. The first thing that was necessary before we could deal with the issue was to set out the scientific basis for action and then to establish an attitude change—at both governmental and individual levels. The science is complex—it involves multiple feedback loops and very non-linear systems in which not everything can be or is known. Yet decisions have to be made because the consequences of waiting could be horrific. And the science cannot be fully separated from people’s values and beliefs.

Much of the public debate over whether man-made climate change is real or not is artificial, a substitute for a real debate over how to respond to the problem. The real issue is one of intergenerational equity—whether to take actions now that have a cost for this generation in order to help the next, or to wait. Waiting is based on the
hope that, even if the problem will be worse if left untouched, a technological solution may present itself, just as it has done in so many other situations which have challenged humans. Rather than debate about differences in values, the issue underlying much of the motivation of the so-called ‘sceptic’ movement, the discussion is reframed around complex science and the extent to which man-made climate change is occurring. Very few unbiased climate scientists think that this question needs much debate—there is more to find out, certainly, but the role of human activity in driving global warming is accepted by nearly all those who do not have vested interests in refuting it. At long last, policy makers have accepted that this consensus merits a discussion about action.