Pregnant women who consumed the caffeine equivalent of as little as half a cup of coffee a day on average had slightly smaller babies than pregnant women who did not consume caffeinated beverages, according to a study by researchers at the National Institutes of Health. The researchers found corresponding reductions in size and lean body mass for infants whose mothers consumed below the 200 milligrams of caffeine per day—about two cups of coffee—believed to increase risks to the fetus. Smaller birth size can place infants at higher risk of obesity, heart disease and diabetes later in life.