From glass to plastic to the seemingly endless range of teat shapes, sizes and flow rates, choosing a bottle set up for your baby can feel overwhelming. To help cut through the noise, we sat down with Susie Warner, founder of Lil’ Kooee, to get her expert opinion based on over 20 years of work in infant consultancy.  Let’s explore whether the bottle and teat you choose really matters.

What are the most important things to consider when choosing a bottle and teat for your baby?

When choosing a bottle, I encourage parents to think about three key things. The material, the venting system and how the bottle supports their baby’s feeding mechanics (regulation of their suck/swallow/breathe pattern). The most important considerations are comfort, safety and encouraging a deep latch. There should be minimal spillage at the sides, no clicking and a strong suck.

Bottle Materials

There are several bottle materials available, each with their own pros and cons. 

Polypropylene (PP) Plastic: Lightweight and widely used. However, due to their maximum heat resistance of 100-110℃, repeated sterilisation can cause the material to become cloudy over time. If bottles begin showing signs of wear, cloudiness or degradation, it’s a good indication they should be replaced (often every 3-6 months). 

Glass Bottles: A very popular choice for parents looking to avoid plastic. They’re easy to clean however, you need to consider weight and breakage. Glass bottles should be checked before each feed for fine line cracks. 

PPSU Bottles: Made from medical grade plastic with a higher heat resistance (180℃). PPSU naturally has a yellow tone so can be difficult to identify if clean. 

Polyamide (PA) Bottles: Made from a nylon polymer – high heat resistance (also 180℃) mitigating microplastic shedding. PA is crystal clear, like glass without the fragile nature. Susie’s Lil’ Kooee bottles are made from polyamide. 

Why does venting matter?

One of the most overlooked bottle features is the venting system. 

As a baby feeds, pressure builds inside the bottle. Effective venting allows air to return to the bottle rather than going into bub’s tummy. Poor venting can contribute to increased air intake during feeds, which may lead to discomfort and colic.

Many anti-colic teat systems rely on additional plastic components that require regular inspection and replacement to avoid microplastics releasing into the milk.

Lil’ Kooee teats have been engineered with an Airshield ® valve, attached to the base that open as the pressure builds inside the bottle. This transfers the air back into the bottle. No plastic funnels to clean and no requirement to pace feed. 

How important is teat flow?

In my opinion, teat flow is one of the most important but also the most misunderstood and unregulated aspects of the bottle industry. Slow flow in one brand can be completely different to another which is why compensation strategies such as pace feeding and side laying have become the norm.

For example:

• Pigeon wide neck soft touch slow flow: 13.16 mL/min
• Pigeon flexible S flow: 12.36 mL/min
• Dr Browns level 1: 13.77 mL/min
• Sepal extra slow: 17.81 mL/min
• Philips avent classic slow: 17.11 mL/min
• Lil’Kooee NB: 4.69 mL/min
• Lil’Kooee SS (1-3 months): 8.98 mL/min

All the teats above are marketed to the same age bracket but as you can see, flows are completely different. 

Signs your baby’s teat may be too fast a flow:

• Spilling milk while feeding
• Gulping or coughing while feeding
• Clicking sound while feeding
• Becoming gassy or unsettled during or directly after feeding
• Require extensive pacing techniques to manage feeds
• Having to sit bub up for 20 mins post feed to stop vomiting

The slower the flow, the more it supports a smooth suck–swallow–breathe pattern and promotes strong muscle development for future chewing and speech.

What is the difference between a wide neck and narrow neck teat?

A very common question that stems from the “breast is best” messaging which has led to popularity of wide-neck teats. However, here’s what the science actually tells us. 

A wide neck teat does not stimulate a baby’s natural sucking reflex which is triggered at the back of the mouth where the hard and soft palate meet. With a wide base, the tongue is pushed forward to stabilise the teat in the mouth rather than being pulled back into a tighter curl, known as lingual cupping. A very important skill later in life, lingual cupping is known to help build the correct oral muscles for speech and chewing. 

In my practical experience, narrow neck teats often encourage babies to achieve a deeper latch and engage their tongue during feeding. This can support:

• A deeper latch
• More efficient milk transfer
• Better coordination during feeding
• Signals the tongue to curl for correct oral muscle development
• Brings the lips in to create an O shape which is important for letter sounds, drinking from a straw and myofascial development.

As every baby is different, I encourage parents to focus less on marketing claims and more on the physical signs of how their baby is feeding.

What is used in the hospitals? 

Maternity wards recognise the distinction between wide and narrow neck teats. When newborns need extra support whilst establishing breast feeding, they are offered a narrow neck teat, not a wide one. 

If babies are not able to suck on a narrow teat, a paediatric dentist, international board certified lactation consultant (IBCLC), speech pathologist or paediatrician should be consulted to check for anatomical differences such as oral ties.  

Can the wrong feeding set-up cause digestive discomfort?

Yes, absolutely! A good feeding set up is vital in ensuring a calm and settled baby. An example being, ingesting too much air, therefore not fulfilling the suck/swallow/breathe pattern. Leading to digestive overwhelm and even poor sleep.

A quick checklist to round this all up

• Regularly inspect teats for cracks, thinning or damage
• Replace teats every few months or sooner if worn
• Sterilise bottles and teats appropriately, especially for newborns*

*UV sterilising machines sold in Australia have not been independently tested for long term safety. A steam/dry steriliser is the safest option to sterilise baby products.