Dr. Brown’s Original Wide-Neck Nipple, Level 4 (9m+) Teat are made of super-soft, high-grade silicone, each nipple level provides a different flow rate.
Dr. Brown’s bottle features a patented two-piece internal vent system that works unlike any other bottle design. The vent system fully vents their bottle for vacuum-free feeding, which they call positive-pressure flow, similar to breastfeeding. As the baby feeds, air is channeled from the nipple collar through the vent system, bypassing the breastmilk or formula, to the back of the bottle. Air never mixes with the breastmilk or formula which minimizes oxidation and helps preserve essential nutrients like vitamins C, A and E.
Babies feed more comfortably because the vent system allows them to nurse without fighting the negative effects of a vacuum or the discomfort of ingesting air bubbles. This helps to reduce feeding problems like colic, spit-up, burping, and gas. The breastmilk or formula flows freely, without nipple collapse.
Dr. Brown’s Nutrient Study Study Reveals Loss of Vitamins A, C, & E in Some Baby Bottles During 20-Minute Simulated Feeding. A released study revealed that after a 20-minute bottle feeding, three nutrients for vitamins A, C and E-all declined during the course of feedings. The results suggest that the amount of air within a baby bottle, the bottle’s design, and the impact on vitamin levels warrant closer examination.