The study by the U.N. Food and Agriculture Organization suggests that reducing malnutrition in pregnant women could prevent their children from becoming fat later in life and ease the impending worldwide crisis in obesity.
The research pulls together growing evidence that suggests hunger during pregnancy sets up babies to get the most out of the limited nutrition while they are in the womb by laying down fat and programs them to expect famine in the outside world.
When they grow up in an environment abundant in food and lacking in exercise — which is increasingly the case as developing nations urbanize — their bodies are not as well adapted as those who were well-nourished as a fetus.
"Many developing countries are currently facing this situation and the impact on their health situation could be dramatic," the agency's report said. "Hunger today and more food availability tomorrow will mean that many will shift from hunger to obesity and become vulnerable to one of the related … diseases, such as diabetes and coronary heart disease."
It may take a few generations to break the cycle because girls who were undernourished in the womb are genetically more susceptible to give birth to malnourished babies, said Hazel Inskip, an epidemiologist at the University of Southampton in England who was not connected with the U.N. report but has conducted research on the topic.
The concept that adult diseases have their origin in fetal and infant development emerged in 1986 from the University of Southampton, but it has gained recognition among scientists in the last five years and has become a hot area of medical research.
Researchers have drawn parallels between low birth weight and later development of problems such as heart disease, obesity, high blood pressure and diabetes.
The theory postulates that when a fetus is undernourished, it diverts resources to areas it needs at the time, such as the brain, at the expense of organs it will need later in life, such as the lungs.
That may permanently change the baby's structure, functioning and metabolism, setting it up to be more vulnerable than normal to the development in adulthood of heart disease and related disorders, the theory holds.
Diets today are not in line with expert recommendations.
The study found that 36 percent of all countries in the world already have populations consuming more than the maximum recommended level of 300 milligrams of cholesterol per person per day. In the early 1960s, only half as many countries were overindulging.
"Likewise, 34 percent of all countries exceed the 30 percent threshold of fat in the diet, compared to 18 percent 40 years ago," the study said.
The U.N. food agency predicts the situation will continue to deteriorate as more than 40 percent of the additional calories consumed in the future will come from fats.
Falling food prices, rising incomes and rapidly increasing urbanization in the developing world mean that diets there are approaching the calorie levels that have for a long time been limited to consumers in rich developed countries.
"These ongoing changes in nutrition mean that a growing number of developing countries face the double burden of under- and over-nutrition," the study said. "The economic problems associated with nutrition transition will be felt more strongly in developing countries."
While people in more advanced countries may be able to cope with the increased costs, the story is very different in developing countries where many people will not be able to afford medical treatment, the agency said.
According to the Centers for Disease Control and Prevention, 64 percent of U.S. adults are overweight or obese, with 30 percent actually obese. Among both adolescents (aged 12-19) and children (6-11), 15 percent are overweight.