Smoking While Breastfeeding

Although it is well known that smoking is harmful for everyone and especially dangerous for babies, some mothers find it very difficult to give up smoking completely. Should mothers who smoke breastfeed? Does nicotine cross into breast milk and would formula be a safer choice? Or will breastfeeding help to protect a baby against some of the health effects of passive smoking?

This article looks at the official recommendations for smoking while breastfeeding, examines how smoking affects breast milk and your baby, and includes suggestions for reducing the risks to the breastfed baby if a mother or her partner can’t stop smoking straight away. For specific information about nicotine see Nicotine in Breast Milk and for nicotine replacement products or e-cigarettes see Nicotine Therapy, Vaping and Breastfeeding.

Can I smoke while breastfeeding?

Yes, say current health guidelines, with the proviso that your baby is protected from breathing in any side smoke and their exposure to nicotine is reduced by smoking after you breastfeed and by smoking as little as possible. Breastfeeding can help to protect your baby from some of the health risks and infections of being exposed to secondary smoke. However, this does not mean that smoking while breastfeeding is recommended. Every effort should be taken to stop smoking and to protect your baby from breathing in any smoke because passive smoking has considerable short and long term health risks for your baby and nicotine does enter breast milk 1 2 3 4.

Health risks of smoking around babies

Babies exposed to cigarette smoke are at a greater risk of cot death or sudden infant death syndrome (SIDS), and are more likely to have respiratory, ear and other infections, pneumonia, asthma, bronchitis, and lung cancer. Babies from smoking households tend to have more colic, be more fussy, have more allergies, have neurobehavioral problems, do less well at school and have a stronger predisposition to become smokers themselves 5 6 7. A mother smoking has also been linked as a risk factor for childhood obesity and thyroid dysfunction 8 9.

Benefits of breastfeeding for your baby

Breastfeeding is known to have significant health benefits for all babies everywhere because it allows normal development of the brain and body systems. It is thought particularly valuable that babies who are subjected to passive smoking receive these health benefits to help cancel out their increased risks of infection 10. Breastfeeding can improve lung function ten years later and help normalise blood levels of important antioxidant vitamins such as A, C and E 11. Formula doesn’t have any of these benefits and carries its own health risks.

However, Mennella et al suggest more research is still needed:

Although lactating women who smoke are advised to stop smoking, breast milk remains the ideal food even if the mother does not stop smoking, because there is little evidence to suggest that breastfeeding from a mother who smokes has adverse effects on the infant (although there are risks related to smoking-induced reductions in milk iodine content). It should be emphasized that the lack of evidence may be attributable to the paucity of research.

Young mother smoking in the garden

How does smoking increase SIDS?

#1 Smoking in pregnancy

One study of data from 2002 found that up to a third of SIDS deaths were connected to smoking during pregnancy 12.

#2 Smoking around baby

Tobacco contains about 600 different ingredients (e.g. arsenic, carbon monoxide, formaldehyde, tar, lead and nicotine) which create thousands of undesirable chemicals when they burn 13. Once smoked, these chemicals travel around the home and cling to your skin and hair, clothing and soft furnishings so that your baby breathes them in long after the cigarette is finished. Passive smoking harms your baby’s breathing, lung function, brain and heart development putting your baby at a much higher risk of those respiratory infections that are connected with sudden infant death syndrome 14.

Nicotine is thought to play a key role in increasing the risk of SIDS by reducing the baby’s ability to maintain their breathing during low oxygen (hypoxic) episodes 15.

#3 Smoking and co-sleeping with baby

It’s important not to sleep in the same bed as your baby if you or your partner smoke as this increases his risk of SIDS 16. On sharing a room if you smoke, the authors of Sweet Sleep say:

Even if you or your partner smokes, most research and health organisations still suggest keeping your baby in your room at night for at least the first half-year. But you can minimise your baby’s nighttime exposure to smoke by keeping his bed away from yours, by bringing him into your bed only for feeds, and by staying between him and a partner who smokes.

See Bed-Sharing With Baby for further information on safe sleep.

How does smoking affect breast milk?

Smoking or passive smoking by the mother can cause:

  • Nicotine in breast milk (and other chemicals). When breathed in to the lungs, nicotine—a toxic, addictive chemical naturally found in tobacco plants—is rapidly absorbed into the mother’s blood, and the baby’s if he is passive smoking, along with tar, carbon monoxide and many other by products 17. High levels of nicotine reach the brain in 10–20 seconds from one “puff” 18. From the blood nicotine quickly diffuses into breast milk. For a review of the ways nicotine can affect a baby via breast milk, how long it stays there, and how to minimise the effects of nicotine see Nicotine in Breast Milk. For information about smoking marijuana see Smoking Weed While Breastfeeding.
  • A lower fat content of breast milk which may affect infant growth and weight gain 1920.
  • Smokey/nicotine tasting and smelling milk which may predispose children to like the taste of cigarettes 21 22.
  • Lower iodine levels in breast milk  are described in a paper by Laurberg et al 23 and this can increase the risk of iodine deficiency-induced brain damage. The authors advise against smoking for breastfeeding women, if they do, iodine supplements should be considered.
  • Lower vitamin C in breast milk see Vitamin C and Breastfeeding.

Breastfeeding and smoking

As well as altering your breast milk in the above ways, smoking while breastfeeding may:

  • Increase the risk of breast abscess and inflammation and mastitis in the ducts behind the nipple (periductal)2425.
  • Reduce the length of the breastfeeding relationship due to a combination of several possible factors including mothers perceiving their milk as not good enough, increased colic and less sleep for their baby 26.
  • Be associated with relapses of Crohn’s disease for mother (Wambach and Riordan, 2015).
  • Affect the let down reflex, milk supply and baby’s weight gain (Wambach and Riordan, 2015 p386) however one researcher found the evidence for these effects was weak 27.
  • Nicotine can cause vasoconstriction, see Nipple Vasospasm and Breastfeeding.

Tips to protect your baby from cigarette smoke and nicotine

  • Stop smoking or try to cut down. A selection of organisations offering tips to help you stop smoking in the UK include; Smoking Cessation, NICE, 2018; Smoking, Smoking Cessation and Breastfeeding, Breastfeeding Network, 2017; Smokefree, NHS Department of Health.
  • Nicotine replacement therapy helps some mothers to stop smoking. See Nicotine Therapy, Vaping and Breastfeeding for a review of nicotine patches, gum, inhaler, and sprays, and for information about e-cigarettes and vaping. And see Nicotine in Breast Milk for more information on the effects of nicotine.
  • Don’t smoke in the home or car or let anyone smoke around your baby. Smoking in another room of the house is unlikely to protect your baby significantly as smoke travels throughout a home and lingers in the furnishings 28.
  • Don’t share a bed with your baby if you or your partner smoke.
  • Smoke straight after a breastfeed not before. The longer the time between smoking and the next breastfeed, the less nicotine will be in your breastmilk.
  • Minimise smoke contact for your baby. Denise Fisher suggests covering hair with a scarf, keeping a smoking shirt to protect your own clothes while you smoke, and washing hands and face after smoking 29.
  • Check your baby’s weight gain regularly as some resources suggest smoking can reduce fat levels in breast milk and affect milk supply. How to Make More Breast Milk provides ideas if there are any issues.


Smoking is a serious health risk to your baby and a risk factor for SIDS. The ideal situation is to stop smoking. If you do smoke, breastfeeding can help protect your baby against some of the health problems associated with passive smoking. However, nicotine is readily breathed in and readily enters breast milk and may cause your baby to have difficulty sleeping, more colic, an increased heart rate, a higher risk of SIDS and may affect his endocrine system (hormones). The impact of other toxic chemicals entering breast milk from smoking needs more research. It’s important to protect your baby from smoke as much as possible and to lower their nicotine exposure via your milk by smoking straight after a breastfeed. Nicotine replacement therapy avoids the risk of passive smoking but e-cigarettes and vaping are still not well researched and their risks haven’t been studied.

Further Reading

This article should not be construed as medical advice. Information found online should always be discussed with your own IBCLC lactation consultant and doctor to ensure it is appropriate for you and your baby’s situation. Contact your doctor, paediatrician or health care provider with any concerns about your baby’s health and welfare.