'Thrifty Phenotype' Hypothesis Gains Ground. (Implications Of Fetal Growth Restriction).

STANFORD, CALIF. -- Mounting validation of the Barker hypothesis has farreaching implications for the practice of obstetrics, Dr. Anthony F. Philipps predicted at a conference on perinatal and pediatric nutrition.

The Barker hypothesis, also commonly known as the 'thrifty phenotype hypothesis, holds that fetal growth restriction is an important cause of some of the most common, costly, and disabling medical disorders of later life: coronary heart disease, stroke, diabetes, hypertension, impaired glucose metabolism, and the metabolic syndrome X.

Dr. David J. Barker, professor of medicine at the University of Southampton (England), first put forth his hypothesis 15 years ago. Since then dozens of largescale studies conducted in Europe, the United States, and elsewhere have convincingly demonstrated a powerful link between fetal growth restriction as reflected in low birth weight and increased risk of developing these chronic medical disorders decades later. "It's a significant body of literature that physicians should be made aware of," commented Dr. Philipps, professor and chair of pediatrics at the University of California, Davis.

The mechanisms involved haven't been corroborated in detail. But in broad outline, the thrifty phenotype hypothesis holds that in periods of nutritional deprivation, the fetus adopts two strategies to ensure survival: It preferentially shunts blood to the brain from key bodily organs; and during a critical window of intrauterine development it engages in programming of organ structure and function so as to maintain long-term metabolic thriftiness later in life under conditions of poor postnatal nutrition.

These fetal adaptations may well have had survival value 20,000 or 50,000 years ago, when starvation was a constant threat. But they probably don't today in the developed world, where circulatory ...