Many mothers are concerned about the impact of lifestyle choices (like alcohol and smoking) when they are breastfeeding. It’s important to understand the effect these substances can have on breastfed babies as well as the impact of exposure in other ways on all babies. Let’s look at each of these in turn:

Can I drink any alcohol?

Most of us are aware that drinking during pregnancy is not advisable, and so understandably a lot of us look forward to the simple pleasure of a nice glass of wine once the baby arrives.

However, for breastfeeding mums, we want to know that our glass of wine isn’t adversely affecting our baby’s health. There is a lot of conflicting information out there, and that’s because the answer to this question isn’t a simple “yes” or “no”.

Lots of people give a blanket “no” answer, because objectively that is the simplest to understand and will eliminate all risk of mothers misunderstanding the guidelines and drinking too much. However, putting unnecessary lifestyle restrictions on mothers may lead to earlier weaning from the breast than would otherwise occur. I am all for protecting our babies’ health – and part of this protection is removing barriers to breastfeeding that need not exist.

Let’s look first at how much alcohol enters the body (and your milk):

Blood alcohol and milk alcohol levels are identical. Alcohol moves into breastmilk (and out of it again!) at the same rate that it moves in and out of your bloodstream. To put this into a context that we are all familiar with, you are “over the limit” to drive in many countries once the level of alcohol in your blood reaches 0.08%.

No meaningful alcohol in milk at this point. At this point, your milk would be considered to have an alcohol level of 0.08%. Surprising fact – this is significantly less alcohol than is found naturally in orange juice! I think we can agree that in any meaningful sense here your milk is virtually alcohol-free.

Alcohol clears from your milk as it does from your blood. As your body breaks down the alcohol in your blood, the levels of alcohol in your milk will be slightly higher, and so the alcohol leaves the milk by diffusing back into the bloodstream to be broken down.

This means that a mother who has consumed some alcohol, but is still under the legal limits for driving, can safely care for her baby and continue to breastfeed.

Why must I limit my alcohol intake?

Sobriety is important. Although a glass (or even two) of wine is fine, it’s not a good idea to drink the entire bottle – not just because of the alcohol that will pass into your milk, but rather because you really shouldn’t be handling a baby when you are drunk (whether you breastfeed or not!).

It can affect let down and supply. Having more than 2 drinks (units of alcohol) has been shown to temporarily lower milk production and inhibit let-down (Coiro et al 1992; Cobo 1974).

Daily consumption can have long term effects. Daily consumption of alcohol has been shown to increase the risk for slow weight gain in the infant and has been associated with a decrease in gross motor development (Little et al 1989).

Can I get rid of the alcohol by “pumping and dumping”?

Unfortunately not. Since your milk is made directly from your blood supply, even if you express milk and discard, your body will simply make milk with just as much alcohol in it, as your blood alcohol will not have changed meaningfully in the 15 minutes it took you to pump.

Is it safe to breastfeed if I am a smoker?

It is undisputed that if you are able to quit smoking, this is the best course of action for your health and that of your baby. However, if this is not feasible right now, it’s important to know that continuing to breastfeed your baby is protective against some of the harmful impacts of living with a smoker, and it is far safer to smoke and breastfeed than it is to smoke and formula feed.

That’s not to say, we advise smoking with abandon – the more you smoke, the greater the health risks to you and your baby, so if quitting isn’t an option, but you are able to cut down, this would be the better course of action.

What causes harm to babies?

There are three main categories of harm caused by smoking: tar, nicotine and smoke.

Tar – The tar in cigarettes moves from the lungs into the bloodstream and is deposited in several sites around a smoker’s body. There isn’t enough evidence to know if this passes directly into breastmilk, but it will definitely be in second hand smoke, so your baby will be exposed via at least one of these channels.
Nicotine – This is the addictive component of cigarettes, with smoking being an extremely addictive delivery method (the faster the nicotine reaches your brain, the more addictive it’s considered to be; smoking takes a mere 7 seconds to deliver the ‘hit’ to your brain). Nicotine replacement therapy delivers a more measured, and slowly delivered dose of nicotine to help manage cravings. One advantage of these over smoking is that we can use our knowledge of the half life of nicotine (90 minutes) to minimise exposure to babies. If a patch is administered immediately following a feed, there will be less nicotine in your system by the next feed. One thing to be extremely cautious of though is patches falling off and sticking to the baby. The direct dose contained within these patches is likely to do significant harm to a baby and so it is very important to be aware of where they are and place them on the body somewhere unlikely to come into contact with your infant.
Smoke - Secondhand smoke is a lethal cocktail of more than 4,000 irritants, toxins and cancer-causing substances. The second hand smoke is not just the smoke you ‘see’ during the time a cigarette is being smoked, but it will linger in the air for 2-3 hours after a cigarette, even with the window open. This smoke will also spread to other rooms in your home, so it is still a risk if the baby is never present when you smoke.

What impact can smoking have on your baby?

Babies who live in a house with a smoker (mother or father) have a 7 fold elevated risk of dying of SIDS (sudden infant death syndrome).
Babies who live in a house with a smoker are more likely to need medical attention for illnesses such as pneumonia, asthma, sinus infections, bronchitis and others.
Babies who live in a house with a smoker are more likely to suffer from colic. If the smoker is a breastfeeding mother, they are also more likely to have symptoms like vomiting, abdominal cramps and diarrhoea.
In the long term, children who have parents who smoke are more likely to grow up to be smokers themselves.

What impact can smoking have on breastfeeding/milk supply?

The evidence for a physiological link to some of these issues is not conclusive and could be due to breastfeeding management, but we do know that the heaviest smokers tend to wean earliest from the breast. Other issues noted from breastfeeding mothers who smoke include:

Slower let down reflex – this can lead to fussiness in babies who are not receiving milk as quickly.
Lower levels of prolactin – this hormone is necessary for milk production, and could be why smokers tend to have greater issues with low milk supply.

How can you minimise the risk?

If you are able to quit smoking, this would be ideal. If you are not able to quit, then cut down as much as possible. This is true for any adults in your household, not just breastfeeding mothers.
Don’t smoke immediately before or during a breastfeed. This would both inhibit the letdown reflex and expose your baby to the maximum toxins.
Nicotine has a half life of 90 minutes, so if you are able to smoke at least 90 minutes before the next breastfeed, exposure to nicotine will be half (or less if longer).
Don’t smoke indoors or near your baby (this is again important for all smoking adults, not just the breastfeeding mother).

Are vapes (e-cigarettes) a safer choice?

Current evidence suggests that many of the harmful elements of cigarettes are reduced in the use of vapes. For example, vapes do not expose babies to tar or carbon monoxide. Ambient levels of nicotine in the air are also approximately 85% lower in vapes than cigarettes.
Although the baby would still be exposed to some levels of nicotine, it would be considered a safer choice than cigarettes. This means that some harm is still caused, but it is certainly the lesser of the two. If vaping prevents you from starting smoking again, then it is probably advisable, but if you could manage with neither, that would be preferred.

Can I drink alcohol, smoke or vape when breastfeeding?

Learn how alcohol, smoking and vaping impacts breastfeeding from Unii Expert Wendy Lever.