Improving public health: a global perspective on the implications of malnutrition in the womb
May 29, 2013
It was British politics that first started David Barker, M.D., Ph.D., FRS, director of international collaborations at the OHSU Bob and Charlee Moore Institute for Nutrition & Wellness and professor of medicine, down a road of groundbreaking discovery that would eventually lead to a new biomedical field called Developmental Origins of Health and Disease (DOHaD).
In the late 1980s, the British government was socialist, and its voters were primarily from the northern part of the country. The fact that coronary heart disease and other related diseases were much more prevalent in the north than in the south had great political resonance for the government and its constituents. The differences in life expectancy of what is a small country were very big.
The government asked Dr. Barker and colleagues at the Environmental Epidemiology Unit at University of Southampton to look at those differences. It quickly became obvious that people's dietary and exercise habits didn't offer a valid explanation. Dr. Barker recalls the moment they realized there must be a different answer: "We said, okay, if they aren't doing something different in the North and the North is historically the poorer area for generations then the only logical possibility is that Northerners are more vulnerable to begin with. Vulnerability arises from your constitution, which is established during development."
To test this hypothesis, he needed records to link birth statistics with health in later life. After scouring the country the perfect records were found in a village in Hertfordshire, a county just north of London. Of note, Dr. Barker had a personal connection to the area – he and his family spent World War II in that same Hertfordshire village of Much Hadham after their London home was bombed; his mother gave birth to his sister there – and it was this personal connection that persuaded the records official to release the files.
The fact that these carefully detailed records even existed can be traced to a local nurse responding to an edict from the British government in the early 1900s to improve the health of mothers and their children. Under that nurse's supervision, any woman in the county of Hertfordshire who was having a baby was attended by a midwife. The midwife recorded the baby's birth weight as well as information from follow-up visits over the baby's first year. These records documented the birth weight of 15,000 residents born in the county before 1930. By comparing them against the state of the residents' adult health, Dr. Barker was able to demonstrate the connection between low birth weight and adult risk for chronic diseases such as coronary heart disease. The Barker hypothesis was conceived and, over the next 15 years, Dr. Barker examined records in the Netherlands, Finland and other countries that would further develop the field of DOHaD.
Study after study has now shown that malnutrition in the womb, often indicated by low birth weight, leads to a higher risk of heart disease, stroke and other chronic diseases regardless of lifestyles and living conditions. But how can we use this information to make a meaningful difference in the health of the human population? In partnership with Dr. Barker, the Moore Institute for Nutrition & Wellness aims to figure out how.
One of Dr. Barker's colleagues is conducting an intervention in the slums of Mumbai, India. For more than 10 years now, they've been running a trial in which married but non-pregnant women get their food supplemented five days of the week. About 1,000 women have taken part and results show clear improvement in the health of babies, indicating that the growth process can be affected. However, Dr. Barker stresses timing as key, with the supplementation starting before pregnancy.
"You've got to start before conception because the fertilized egg, and probably the unfertilized egg, is sensing the mother's nutrition state very early – day one, day two, long before the egg even gets to the uterus. We know the egg is 'reading' this information because we've been able to show this experimentally in other mammals," he said.
The ability of a woman to effectively nourish her fetus depends on the nutrition she gets throughout her lifetime, which is the product of her growth and nutrition beginning in her mother's womb. Food supplementation before pregnancy can affect the fetal growth process, but it will not set the child's metabolism. The body's ability to process proteins, for example, is established by the time of weaning and is set from that time onward. Therefore, according to Dr. Barker, if the Moore Institute intends to play a significant role in promoting the health of the next generation, it must emphasize the diets of girls throughout their lifetimes.
About 10 years after Dr. Barker completed that first study in Hertfordshire, officials in Southampton, England, decided to do something about the health of poorer people in their city. So they called in Dr. Barker and his team. The researchers asked women in the community about the existing barriers to eating well and providing nutritious food to their children. The responses ranged from lack of money and proximity to food sources, to lack of knowledge around food preparation. Based on these one-on-one conversations with local women, the intervention team developed a plan to implement changes to nutrition around the time of conception. Once the women understood the implications they were the real drivers of change, speaking out in the community and making changes in their homes. The Southampton Women's Survey continues today and follows fetal and childhood development in the women who become pregnant.
Dr. Barker joined OHSU in 2003 to work with Kent Thornburg, Ph.D., professor of medicine and director of the Moore Institute for Nutrition & Wellness. Now, as the Moore Institute's director of international collaborations, he offers his own vast expertise and an invaluable connection to international studies in the field of DOHaD.
The studies from Southampton and Mumbai, among others, are already helping to inform and advance the work of the Moore Institute. To start, a study based on the Southampton model will be piloted in Astoria, Ore., and led by the Moore Institute's co-director, Jonathan Purnell, M.D. Researchers from the Southampton study have visited OHSU and Astoria to consult on the project thanks to Dr. Barker.
Dr. Barker emphasizes the need for global research relationships when discussing his role with the Moore Institute. The way he sees it, you're not going to figure out how to make Americans healthier just by staying in America. The more global data available, the better connections you have for piecing together solutions. International studies, Dr. Barker says, are a practical piece of the puzzle.
And for him, it's a crucially important puzzle to solve now. "What we're looking at today are projections that by the time your baby is grown, one in three Americans will have Type 2 diabetes. That makes the Black Death look like nothing. So there is a real urgency to this."
Pictured: David Barker, M.D., Ph.D., FRS