NutriGrow : The Perfect Formula

Bottles and Nipples: Complete Guide


All parents should learn about bottles and nipples before their baby arrives.

Although bottle feeding is more often associated with infant formula feeding, it can also be used for breastfeeding. That is, in cases where the mother pumps her breast milk and the baby takes it through the bottle.

In either case, regardless of the option you choose to feed your baby, there are a number of factors you need to know to choose the best bottle and nipple.


Below we will tell you what points you need to consider when choosing the most appropriate bottles and teats for your baby.

We will also give you some advice on the guidelines you should follow regarding its cleaning and sterilization.


Choosing the right bottle for your baby is sometimes a task that many parents overlook.

"If you want your child to feel satisfied in his first days of life and during his growth it is important that you give him the best"

Nowadays, there is an enormous variety of baby bottles, so there are several points to consider when choosing the most suitable one for your baby.

Before choosing any of the bottles you can find in the shops, you should consider a series of factors that will give you the best comfort when feeding it.

Factors to consider before buying a bottle

Bottles are usually classified according to size, shape, material and type of nipples.

Each model has its advantages and disadvantages. Also their own characteristics that make them more or less:

  • Hygienic
  • Easy to clean
  • Resistant
  • Insurance
  • Appropriate according to the age or taste of the child

Take note, because below we will tell you all the important aspects you should consider when choosing a bottle for your baby.

What is the ideal shape of the bottle?

When considering the shape of the bottle, the variety is very wide, there are cylindrical, triangular, wide, including handles, etc.

Let's look at some characteristics of each:

Cylindrical: these are the classic feeding bottles and are well suited to all uses.

Triangular in shape: they favour grip and have greater stability.

Wide-format: they are more stable and also easier to prepare and clean.

Ergonomic: they are designed to be held more easily by the baby. Some include handles to help the baby learn to drink independently.

Anti-Colic and Anti-Reflux: they have a curved shape that reduces the amount of air ingested by the child during intake.

With double anti-colic effect: they are designed to prevent air intake and reduce reflux and gas accumulation. In addition, some models have a removable base for easy cleaning.

What are the bottles made of?

Bottles are made of these two types of materials:

  • Glass
  • Plastic (polypropylene)

Each has its advantages and disadvantages. Let's look at some characteristics of each one below:

Glass feeding bottles

They do not absorb colours, odours or flavours. They are also more hygienic and easier to clean.

The glass is also heat-resistant so it maintains the temperature of the milk for longer. 

They tend to be kept in better condition over time. However, glass is a fragile and heavier material to transport.

Plastic Bottles

Polypropylene bottles are lighter and easier to carry. 

They are also stronger and do not break when they fall to the ground. This characteristic makes them suitable for when, from the second semester onwards, the baby starts to hold the bottle by himself.

It should be clarified that both are very safe because their manufacturing material does not release substances. Both can be sterilised hot and cold and can be heated in a microwave.

Parents often choose glass bottles for feeding their babies during the first stage, because they give more priority to hygiene and cleanliness.

From the time their babies are six months old, they often switch to polypropylene bottles, as they are safer for children to hold on their own.


If you buy plastic bottles, make sure they are free of BPA, PVC and PC. These are chemicals that can be found in plastic and are hazardous to a young child's health.

Anti-Colic Bottles - What are they and what benefits do they offer?

Children who cry too often because of infant colic can improve this problem with bottles that mimic breastfeeding.

Anti-colic bottles are bottles that allow air to enter as the baby sucks, so that the baby can regulate the rate at which the liquid exits without much effort.

These systems have a different design and mechanism than traditional baby bottles, as they allow the milk to come out more easily. They are designed to imitate the way the baby pumps the milk from the mother's breast.

The secret of anti-colic bottles is in the cannula; perfectly located in the neck of the bottle, it encourages the flow of air to the bottom. In this way, the baby can feed himself calmly, without the bubbles that can form ending up in his belly and causing colic.

Bottle size

The size of the bottle to be used will depend on the baby's age and weight.

The bottles can be sorted into:

  • Small: 90 ml. approx.
  • Medium: 120 ml. approx.
  • Large: 240 ml. approx.

Depending on the age, these are the approximate amounts per intake and the approximate number of daily intakes:


90 ml. to 120 ml. per dose. Between 8 and 12 times a day every 3 hours approximately.


From 120 ml. to 180 ml. per shot. Between 8 and 12 times a day every 3 hours approximately.


From 120 ml. to 240 ml. per intake. Between 7 and 8 times a day. From 6 months onwards you should start adding solid food to your diet.

Remember that these data are approximate, and should be adapted to the specific needs of each baby.

In any case, the best thing to do is to always follow the advice of your pediatrician.

¿How many bottles should a newborn baby have?

The answer to this question will depend on how you feed your baby during the first few weeks of life.

If you plan to breastfeed your baby and are sure that this will be your only feeding for the first few months, then it is not necessary to have more than two bottles at home. You would use them in case you needed to express your milk and then give it to your baby.

However, if you choose to feed your baby formula because you do not want or cannot breastfeed, then you will need to have several bottles at home.

It's usually recommended that you have about six bottles.

Keep in mind that if your baby is exclusively bottle-fed, he or she will take at least 7 or 10 feedings a day.

If you have several units, you won't have to constantly wash and sterilize your bottles.

As your baby grows, you will also use the bottles to give him water, juice, herbal teas or his medicines.

¿How often are bottles replaced?

The bottle is an element to which you must pay special attention, as it will be in direct and constant contact with your baby's mouth. For this reason it is essential to clean and sterilise them correctly, as well as replacing them when necessary.

Three guidelines that tell you it's time to replace the bottle:

Plastic or glass is scratched, worn or cracked. Germs can stay on the scratched parts no matter how much you clean the bottle.

The bottle has cracks, splinters or breaks. Your baby could be cut, poked, or hurt in some way. This is even more dangerous if you use glass bottles.

Your baby's growing up. As a general rule, babies change the size of their bottles (and teats) every trimester of growth. Your child will set the pace at which you need to replace the size of the bottle with larger ones.

By following these three simple guidelines, it will be easy for you to know when to replace the bottle so that your baby is safe and satisfied at every feeding.

The nipples

The teat is an element of the bottle that tries to simulate the mother's nipple.

Photo by Koosen on Adobe Stock

Its function is to allow the liquid contained in the bottle to drip out of it.

It is a very important piece that needs special attention.

Points to consider when choosing the right teat

There are several criteria used to classify the nipples and we will see them all below.

Nipples according to their shape

There are three types of nipples according to their shape, these are

  • Round teats (also called gout)
  • Anatomical nipples
  • Physiological teats
Round nipples

These are the ones that have been used traditionally. They have a rounded shape and many babies prefer them, although they can contribute to deforming the palate.

Anatomical nipples

They are flattened and fit well to the baby's palate to avoid deformation, but this makes them narrower and more uncomfortable for some babies.

Physiological teats

These nipples imitate the mother's nipple. They have a more elongated design and roughness that makes them easier to grip. They are ideal for starting the transition from breast to bottle.

The teat, in any of its forms, must allow the flow of milk to be regulated, ensuring that it always comes out at a constant and moderate rate.

The milk output and the air intake indoors must be compensated, either to avoid over-stressing the suction, or to prevent the child from swallowing too much air.

What material should the nipples be made of?

There are two materials from which the nipples are normally made:

  • Latex (or rubber)
  • Silicone
Latex nipples

They are soft and elastic, offering a comfortable feeling during sucking and are perfect for switching from breast to bottle and back again easily.

Latex is a yellowish natural rubber.

However, it is a material that tends to break down more easily. When it absorbs water the teat ends up swollen and becomes opaque, so you will have to discard it.

Latex nipples

They are much more hygienic, completely transparent and soft. They are also odourless and tasteless.

These nipples are quite elastic and do not absorb water, so they do not alter as can happen with latex nipples, even after repeated sterilizations.

The disadvantage of silicone nipples is that, as they are softer, they tend to break when the baby's teeth come in, so from this stage onwards, latex ones are more recommendable.

Disposable teats

The "disposable teats" are also on sale. Many parents opt for these single-use teats when traveling with their children, or for going outdoors.

The disposable teats are already sterilized and, as the name suggests, should be thrown away once they have been used.

Another criterion to take into account is the flow of the teat. We will see this below.

Nipples according to their flow

According to the liquid flow they allow, the nipples have the following classification:

  • Slow-flowing
  • Medium flow
  • Fast flowing
  • Variable flow
Slow-flow nipples

They are recommended for newborns, or for babies who have more difficulty with bottle feeding, because the milk comes out very slowly.

Medium Flow Nipples

These are used from 3 months onwards, when babies already have some "handling" of bottle feeding and also need a greater amount of food.

Fast Flow Nipples

They are normally used from the age of 6 months, when babies are already able to suck without problems and also drink more milk.

Variable Flow Nipples

They are ideal for any baby, regardless of age or sucking ability, because they are equipped with a system that allows the flow to be regulated.

The differences between all of them is the amount and/or size of their holes.

Size and number of holes

LEVEL 1: one hole, ideal for newborns to three months

LEVEL 2: one hole, for babies over three months

LEVEL 3: two holes, for over six months

LEVEL 4: two holes, for children over 9 months (ideal for thicker substances)

Y-CUT: three holes, for children over 9 months (special for cereals)

The number of holes according to the level may vary according to the manufacturer.

Nipples according to their width

The nipples are also classified according to their width:

  • Wide mouth
  • Narrow-mouthed
Narrow-mouth nipples

These are the ones used in the classic baby bottles that are more elongated. They are usually more complicated to clean.

Wide-mouth nipples

They are used in thicker bottles and are easier to clean, although not all babies like or adapt to them.

When do you have to change the nipples on the bottle?

As a general rule, it is advisable to change them whenever they are deteriorated, deformed (due to use), or the flow of the milk outlet is no longer sufficient for the baby's intake, since, as it grows, the flow must be greater.

The child will set the pace at which he or she needs to replace the flow of the teats with the faster ones. Babies usually change the size of their bottles and nipples every three months.

Tricks that can guide you

Change the nipple if...

  • You see that he has trouble sucking or gets tired when he takes the bottle. If this happens, it is probably because she has outgrown her bottle and needs a medium or fast flow (the latter from 6 months onwards).
  • If you notice that he cries when he eats, you see that he sucks hard but barely empties his bottle.
  • If it takes longer than 20 or 30 minutes to take it.
  • If you spill or leak too much milk and swallow too much, you may need a slower-flowing nipple.

We recommend that you do not choose a teat lightly.

Always check that it is an approved product in your country, and I have the corresponding stamps that indicate that they comply with all the hygienic and sanitary requirements.

Tips for cleaning bottles and teats

During the first days and months of your baby's life it is important to keep the teats and bottles in good condition.

During this time, babies have not fully developed their immune systems, a condition that makes them more defenseless against infectious agents.

Cleaning the bottle when it has just been used:

When your baby has finished drinking the bottle, discard any remaining milk or formula and rinse with water.

Then, using soap and water together with a specific bottle brush, you rub the walls of the bottle to remove the remains.

You do the same with the nipple.

Finally, rinse the bottle and teat in plenty of water and let them air dry. Do not use kitchen towels to dry them as they may contain bacteria.

Once they are dry, store the bottles in a clean place intended for this purpose.

Every so often and before the first use, it is necessary to sterilize the bottle and teat.

¿How to sterilize bottles and teats?

Sterilizing your baby's bottles, pacifiers, and other items is necessary to maintain proper hygiene when babies are very young.

Until the baby is three months old, to guarantee hygiene, it is not enough to simply wash, but it is also necessary to sterilize bottles and other objects.

Babies at this age do not have fully developed immune defenses, so they are more exposed to the risk of getting intestinal infections, with consequent vomiting, diarrhea and fever.

"Don't forget sterilize bottles and nipples at the time of purchase, or before first use"

Sterilization begins with careful washing of your hands with warm water and soap and the surface of the place where they are stored.

Before sterilisation proper, wash the bottles and teats with hot water, detergent and a brush to remove any milk residue. Finally, rinse the objects with tap water.

There are different methods of performing sterilization, all of which are equally effective.

Heat Sterilization Method

There are two heat-based sterilization systems: 

  • The boiling
  • The steamer
Boiling sterilization method

It consists of putting the objects to be disinfected into a pot or sterilizer basket and filling the container with water until they are completely submerged. 

Then, let the water boil for 15-20 minutes and keep the objects in the pot with the lid on until the time of use.

Steam sterilization method

It requires the use of an electric kettle that transforms water into steam. 

Place the bottle or objects in the basket and pour the water into the container. Then close the lid tightly and operate the machine. 

After 15 minutes, the steam output will indicate that the impurities and microorganisms have been removed and that sterilization has taken place.

Cold sterilization method

First, the objects to be sterilized must be introduced into the container and filled with water up to the indicated level.

Then, the disinfectant substance is added without exceeding the recommended amount, the objects are completely submerged, making sure that all the air comes out, and the substance is left to act for 30-90 minutes (depending on the type of disinfectant used).

When using, objects should be removed from the water with suitable tweezers (do not insert your hands!) and used without rinsing.

Since the solution remains active for 24 hours, objects can be immersed more than once during the day.

Microwave sterilization method

The microwave oven can also be used for sterilization. All you have to do is buy a special container with a lid, which is particularly heat-resistant, in which you can colour the bottles and teats with a little water and heat them up for about 4-8 minutes.

If the bottles and other objects have been properly sterilized, they can remain at room temperature for several hours, so that airborne germs are not able to cause infection.

Bottle teats should be stored in a dry, clean, covered container after sterilization.

When to sterilize bottles

Pediatricians recommend sterilizing bottles, nipples, pacifiers, and other objects that a child can put in his mouth up to four months after each use.

From the age of four months, however, it can be further sterilized every 15 days to prevent milk or germ residues. The rest of the days, it is sufficient to wash them well with hot water and soap.

From the age of six months it will no longer be necessary to sterilize.

You can even put bottles, nipples and other items in the dishwasher if you choose a program that is more than 80 degrees.

This is so, since you can't keep the child in a bubble. For your child's immune system to become strong, it needs to come into contact with bacteria.


The bottle is one of those essential elements in the development of our baby. 

Even if you have decided to breastfeed your child, there will come a time when you will need to use bottles. This may be when your child is not with you, for example while you are working, or in other less common situations. For example, when using a medication that is not compatible with breastfeeding.

There are different models on the market, which are classified according to size, material and even by the type of nipple.

The bottle should be practical, functional, easy to clean and appropriate for your baby's age.

When choosing the teat, you should prioritise your child's comfort, which will depend on the shape, size and material of the product. 

Bottles and teats should be cleaned after each use.

They should also be sterilized before first use, and during the first 6 months of your baby's life.

The frequency of the sterilization procedure will depend on the stage of growth your child is in.

Every time you use the bottle, it is advisable to make a visual inspection to check that the teat is in perfect condition, especially if your child already has teeth and can bite them.


The information presented on is not intended to provide or replace the advice of your pediatric physician or medical nutritionist. 

The information presented in this post is not intended to diagnose, treat, cure or prevent any disease. Full medical clearance must be obtained from a licensed physician before modifying a child's diet. 

The authors assume no liability to any person or entity for any liability, loss or damage caused or alleged to be caused directly or indirectly as a result of the use, application or interpretation of the information presented in this post.


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