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Breast cancer is the most common type of cancer in women. An estimated 12.9 percent of women will be diagnosed with breast cancer at some point in their lifetime, based on data collected from 2015 to 2017.

There are several risk factors for developing breast cancer, including genetic and lifestyle factors. You may also be wondering if smoking is linked to breast cancer since it can be a risk factor for other types of cancer.

The relationship between smoking and breast cancer risk is still unclear. However, some smoking habits may increase a woman’s risk of developing breast cancer.

Continue reading as we break down what researchers know about smoking and breast cancer. We’ll also discuss the other risk factors for breast cancer and when to get medical attention for symptoms of breast cancer.

According to the Centers for Disease Control and Prevention (CDC), over 16 million people in the United States are living with a disease caused by smoking. In fact, smoking can cause harm to almost every organ in your body.

Tobacco smoke contains more than 7,000 different chemicals, and at least 250 of these are known to be harmful to the body. When you breathe in cigarette smoke, these chemicals can enter your lungs and spread to other areas of your body.

The harmful chemicals in cigarette smoke can cause mutations in your DNA, potentially leading to cancer. In fact, smoking can cause many different types of cancer, including — but not limited to — cancer of the lungs, cervix, and colon.

Is there a direct link?

A 2014 report from the Surgeon General evaluated available studies on the potential health consequences of smoking. It found sufficient evidence of potential ways in which smoking may cause breast cancer.

However, the report concluded that while the evidence is suggestive, it’s not enough to say that smoking or exposure to secondhand smoke causes breast cancer. More research is needed to establish a direct link between smoking and breast cancer.

What does the current evidence show?

There are some things that research has told us about smoking and breast cancer. Let’s examine what we know.

It appears that breast cancer risk is linked to a smoking habit that’s lasted for many years. For example, people with a history of smoking have about a 10 percent higher breast cancer risk than people who’ve never smoked.

A 2011 cohort study found that the risk of breast cancer increased in women who:

  • currently smoke or previously smoked a large number of cigarettes
  • started smoking at a younger age
  • smoked for many years
  • smoke a higher number of pack-years, with risk increasing with every 20 pack-years
  • smoked before the birth of their first child

A more recent 2017 study looked at data pooled from 14 different cohort studies and found that:

  • The overall association of smoking with breast cancer was modest.
  • Smoking for more than 10 years before the birth of a first child carried a high risk of breast cancer.
  • Smoking 40 or more cigarettes per day was associated with the highest risk of breast cancer.
  • Drinking alcohol can have a compounding effect on breast cancer risk, particularly when heavy drinking is combined with smoking a large number of cigarettes or smoking for many years.

Exposure to secondhand smoke may also increase a woman’s risk of breast cancer. A 2013 cohort study found that women who were frequently around secondhand smoke had similar breast cancer risk to active smokers.

Smoking may also negatively impact women who currently have breast cancer. A 2014 study found that current or previous smoking, particularly heavy smoking, was associated with a poorer outlook and an increased chance of cancer recurrence.


Research into the link between smoking and breast cancer is currently ongoing. From what we know so far, breast cancer risk is higher for women who:

  • have smoked for many years
  • currently or previously smoked a large number of cigarettes
  • smoked from a young age, particularly before the birth of their first child
  • drink heavily, particularly when combined with smoking many cigarettes or smoking for many years

Cannabis (marijuana) smoke can contain similar amounts of volatile chemical and tar components as tobacco smoke. This has raised concerns about links between cannabis smoking and cancer or lung disease.

However, less research has been done on this topic. A 2019 meta-analysis reviewed 25 studies that looked into a possible link between smoking cannabis and cancer.

Overall, it found that the association between cannabis smoking and cancer was unclear. Only a low association between long-time cannabis smoking and testicular cancer was found.

The analysis only included one study investigating cannabis smoking and breast cancer, finding no link between the two. The reviewers commented that the evidence from this study was insufficient and more research is needed.

Medical cannabis

Many people who have been diagnosed with cancer use medical cannabis to help ease their symptoms and treatment side effects, such as:

If you’re interested in using medical cannabis, it’s important to check your state’s laws, as it’s currently only legal in certain states. However, some other states have legalized a specific cannabis ingredient, cannabidiol (CBD).

Here are a few other tips if you’re considering using medical cannabis:

  • Talk with your doctor. Medical cannabis may interact with other medications or supplements you’re taking, so be sure to talk with your doctor first.
  • Use medical-grade cannabis. Ask your doctor about dispensaries that specialize in medical cannabis. These locations should have pharmacists or staff that are knowledgeable about their products and can answer health-related questions.
  • Consider how to use it. There are many ways to use medical cannabis, including:
    • smoking or vaping
    • eating edibles, such as gummies or cookies
    • taking pills or gelcaps
    • inhaling oils
    • applying creams or gels
  • Check your employer’s policies. In some types of jobs, it’s possible to face disciplinary action if you’re found to be using cannabis. Always check to see if your employer has a medical cannabis policy beforehand.
  • Expect some trial and error. Medical cannabis affects everyone differently. You may have to try several different products or ways of taking it before you find something that works for you.

While smoking may increase the risk of breast cancer in some women, there are additional breast cancer risk factors to be aware of.

Risk factors you can’t change

There are several breast cancer risk factors that you cannot change. These are typically related to your overall health, genetics, or family history and can include:

  • Age. A woman’s risk of breast cancer increases as she gets older.
  • Genetics. Some genetic mutations raise the risk of breast cancer. Some that you may be familiar with are BRCA1 and BRCA2.
  • Personal history. If you’ve already had breast cancer, you’re more likely to develop it again. Additionally, having certain noncancerous breast conditions, such as atypical hyperplasia, is associated with an increased risk.
  • Family history. Having an immediate family member, such as a parent, sibling, or child, who’s had breast cancer increases your breast cancer risk.
  • Reproductive history. Risk increases when menstruation happens early or menopause begins later. Risk is also higher for women who:
    • have never given birth
    • are at an older age at the birth of their first child
    • don’t breastfeed
  • Having dense breasts. Women with dense breast tissue are at a high risk of breast cancer. Additionally, having dense breasts can make tumors more difficult to see with common screening methods like mammograms.
  • Previous radiation therapy. If you’ve previously had radiation therapy on your chest for another type of cancer, your risk can be higher.

Risk factors you may be able to change

There are some types of risk factors that you can take steps to change. These are most often related to lifestyle and include:

  • Drinking alcohol. Breast cancer risk rises with higher levels of alcohol consumption.
  • Weight. Being overweight or having obesity, particularly after menopause, increases your risk of breast cancer.
  • Physical activity. Having a low level of physical activity raises breast cancer risk.
  • Taking hormone medications. Taking some types of combined hormone replacement therapy after menopause or using some types of oral contraceptives may increase breast cancer risk.

The most common early symptom of breast cancer is a new lump, mass, or thickening in the breast. These can be detected on routine imaging or when performing breast self-exams.

Often, these lumps feel hard and have irregular edges. However, it’s also possible for a lump to be soft and more uniform in shape. Typically, lumps due to breast cancer are painless.

If you notice a new or concerning breast lump, be sure to talk with a healthcare professional. They can use various screening and diagnostic methods to help determine if the lump may be cancerous.

Other potential signs of breast cancer can include:

In addition to increasing the risk of many types of cancer, smoking can also lead to conditions such as heart disease, stroke, and lung disease. Secondhand smoke can also have many harmful health effects.

If you do smoke, it’s important to quit. Quitting smoking is a powerful tool for improving your overall health and lowering your risk of cancer and other chronic health conditions.

However, quitting smoking can often be a difficult process. If you’re trying to quit smoking, try using the resources below to help you on your journey.

Consult with a doctor

If you’d like to quit smoking, be sure to let a doctor know. They can work with you to develop a plan, recommend a nicotine replacement therapy, or help you find a counselor or support group.


A quitline is a telephone-based service that can help you take steps to quit smoking. An example of a quitline is 800-QUIT-NOW (800-448-7848), the National Cancer Institute Smoking Quitline.

State and local quitlines are also available. You can search for them here.

The National Cancer Institute created It offers a variety of resources to help people quit smoking. Some examples of these resources include:

  • information on the different ways to quit smoking
  • assistance in creating a quit plan
  • details on challenges you may experience while quitting, such as cravings or withdrawal, and how to address them
  • apps and text messaging programs to aid with your quit goals
  • access to counselors either by phone or via an online chat

Quit smoking apps

There are many different apps available for both iPhone and Android that can help you quit smoking. We’ve reviewed some of the best ones here.

Current research indicates that certain smoking habits can increase the risk of breast cancer. These can include smoking for a long time, smoking a high number of cigarettes, and smoking before the birth of a first child.

While additional research is needed to confirm a link between smoking and breast cancer, there are other known risk factors for breast cancer. These include things like genetics, age, and alcohol consumption.

Quitting smoking is essential both for improving health and preventing chronic health conditions. If you’d like to quit smoking, talking with your doctor is a good first step to learn about your options and develop a quit plan that works for you.