天博体育

Heart disease. Stroke. Diabetes. Asthma. Osteoporosis. These common scourges are often pegged to genes, pollution, or the wear and tear caused by personal choices like a poor diet, smoking, or too little exercise. David Barker, a British physician and epidemiologist, has a different and compelling idea: these and other conditions stem from a developing baby鈥檚 environment, mainly the womb and the placenta.

Barker was the invited speaker at this year鈥檚 Stare-Hegsted Lecture, which is a big deal at the . In just over an hour, he covered the basics of what the British Medical Journal used to call the Barker hypothesis. It has since come to be known as the developmental origins of chronic disease. (You can watch the entire talk .)

It goes like this: During the first thousand days of development, from conception to age 2, the body鈥檚 tissues, organs, and systems are exquisitely sensitive to conditions in their environment during various windows of time. A lack of nutrients or an overabundance of them during these windows programs a child鈥檚 development and sets the stage for health or disease. Barker and others use low body weight at term birth is a marker for poor fetal nutrition.

When a fetus is faced with a poor food supply, it shunts nutrients to its most important organ, the brain. The heart, kidneys, muscles, bones, and other tissues don鈥檛 develop as they should. The nutrition debt they incur appears years later as one or more chronic diseases.

According to Barker, four factors influence a baby鈥檚 development:

• the mother鈥檚 day-to-day diet
• the nutrients stored in the mother鈥檚 body
• the mother鈥檚 metabolism
• the placenta, an organ formed by the developing baby that captures nutrients from the mother and transports them to the baby.

鈥淭he least important of these is the mother鈥檚 diet during her pregnancy,鈥� Barker told the assembled crowd of Harvard students and faculty members. 鈥淎 baby lives off its mother鈥檚 lifetime nutrition.鈥�

The take-home message is that growing healthy children requires improving nutrition for girls and women through their lifetimes, not just during pregnancy.

So far, Barker鈥檚 idea is just an interesting hypothesis. Some data support it, other data refute it. Some researchers, like Harvard鈥檚 , believe there鈥檚 more to the story. One problem is that birth weight is a 鈥渄readful marker鈥� for prenatal influences, as Gillman writes in the . Another is that so-called catch-up growth during infancy or youth may compound the effects of prenatal programming. Several studies suggest that the combination of low weight at birth and becoming overweight early in life is a potent recipe for later heart disease.

Even though the developmental origins of chronic disease is still an idea in gestation, it has gained some popular attention. For example, science writer Annie Murphy Paul covered the idea in her book, Origins, which was featured on the in September 2010.

It鈥檚 still a bit too soon to base public health messages on Barker鈥檚 hypothesis. But it does reinforce the simple idea that a healthy diet in youth, adolescence, young adulthood, and pregnancy is one of the best gifts a woman can give to her future children and grandchildren.