#014: Smoking and MS. Why and how to quit? Interview with Dr. Claudia Marck

Today I talk with Dr. Claudia Marck about smoking and its impact on multiple sclerosis. Claudia gives tips on how to successfully become a non-smoker. She knows what she is talking about as she used to smoke intensively herself and it took her several tries to finally stop. But she has been a non-smoker for 15 years now and is very happy about it.

We talk about how smoking increases the risk of disease onset and worsens prognosis. And after providing all the evidence on why you should quit, Claudia shares proven methods on how to achieve that goal.

This interview was originally recorded for the German MS-Perspektive podcast in April 2023. Since the content is so important, I am publishing it for the English podcast and blog again.

This podcast episode and blog post exist in German as well.

Klicken Sie auf den unteren Button, um den Podcast zu laden.

Podcast laden

Table of contents

Introduction of Dr. Claudia Marck

Dr. Claudia Marck is smiling friendly towards the viewer


Claudia is Dutch by birth and moved 15 years ago to Australia.


Senior Research Fellow at Melbourne School of Population and Global Health


  • Management: Swinburne University of Technology
  • Dr: Erasmus University Rotterdam
  • Neuroscience and cognition: Utrecht University
  • Psychology: Utrecht University 

Personal motivation for your career choice

Multiple sclerosis is a disease that impacts many people from a young age, often in the years when they are building careers and families. With my work I hope to find ways that I can help people with MS to live healthier and happier lives. think helping people to quit smoking hasn’t received enough attention in MS research and clinical practice. I used to smoke a pack a day. I quit smoking 15 years ago after several attempts, so I know how hard it can be.

Smoking and MS – existing evidence

Which effect has smoking on the onset of multiple sclerosis (MS)?

We have quite convincing evidence now that smoking increases the chances of developing MS. Passive smoking, so being around people that smoke, also increase the risk of MS. This is important for children of people with MS, who may be at slightly higher risk of developing MS themselves due to genetic vulnerability. One study showed that children whose parents smoked around them had higher risk of developing MS at young age, and the longer they were exposed to smoke, the higher that risk was.

How does smoking contribute to the disease and disability progression?

People who continue to smoke after a diagnosis of MS are worse off than people who stop smoking at the time of diagnosis in terms of brain lesions, relapses, and disability progression. Studies following people with MS over long periods of time have shown that people who continue to smoke develop walking difficulties quicker. Several studies show that people with RRMS who continue to smoke also reach the progressive stage of MS (SPMS) quicker than those who don’t smoke. One study showed that persistent smokers reached the progressive stage of MS eight years earlier compared with those who quit after diagnosis. We all know that smoking also impacts on heart health and your other organs and increases the risk for cancer. It is never too late to quit smoking; even if you have had MS for a very long time, quitting smoking will be one of the best things you can ever do for your health.

How many people are smokers at the time of diagnosis?

This is unclear. There is some evidence to suggest people with MS more commonly smoke compared to people without MS, but more research is needed in this area. This is also different in each country. In Australia where I live, we have had much stricter regulations for smoking advertisement, and a pack of cigarettes is much more expensive than in Germany. Therefore, the proportion of smokers in the population is lower, about 11% in Australia compared to 22-28% in Germany, so that’s double.

What does smoke to the body and brain and is there a difference between normal cigarettes and e-cigarettes?

First, as we age, all of us, our brains slowly shrink a little. Smoking has been shown to speed up this process because the smoke causes injury to brain cells day in day out. There are also metals and many chemicals which can cause cancer, damage blood vessels, the lining of the lungs, the heart muscle and pretty much every other organ in your body. Most of us know this, but smokers generally die younger and this is also the case for people with MS who smoke vs people with MS who don’t smoke. There is no evidence to suggest that the e-cigarettes are not harmful, they often have a lot of chemicals which have the potential to be harmful. E-cigarettes or vapes haven’t been around long enough to know what the long-term health consequences are. Current advice is not to use these unless prescribed by your doctor specifically as a temporary tool to quit.

Which ingredient seems to be the most dangerous one? And is it present in chewing tobacco as well?

I don’t know which is the most dangerous. Some of the dangerous chemicals in tobacco smoke include formaldehyde, lead, arsenic, ammonia and tar, which is what stains fingers and teeth of smokers yellow or brown. Studies have shown that nicotine, while addictive, is not what causes the harms to your health (unless in large doses) It’s the other chemicals and the smoke from cigarettes and cigars that do most harm. This is important, because it means that nicotine replacement products, which can be helpful with quitting, are safe for people with MS. There are no known interactions with MS medication and nicotine, or with other quitting medications. As far as I’m aware there are no strong links between chewing tobacco and MS, but there are other health risks and therefore it’s better not to use it.

Has smoking any impact on the success of disease-modifying treatments (DMTs)?

Yes, smoking impacts on how effective MS medication is at slowing relapses. Two studies have looked at natalizumab and interferon beta, which were less effective in people with MS who smoked. These medications are designed to slow down MS, so we don’t want to interfere with their efficacy. It’s important to note that there are no known side effects between nicotine replacement therapy, like the chewing gum and patches, and MS medications.

What is the effect of smoking on the quality of life for people with MS?

I think this is a difficult question to answer because it’s hard to know the cause and effect. We know that people who have more difficulties in life are more likely to smoke, and this worsens their health. People with for instance depression or pain can have more difficulty quitting smoking because it may give them temporary relief, even if it might make it worse in the long term. We do know that once people quit, their mental and physical health improves.

What happens when smokers become non-smokers and how long does it take to see positive impacts on the disease progression?

Unfortunately, studies show that the damage does not resolve when people quit. So you may not see improvements perse, but the rate of worsening will slow down to be similar as people who have never smoked.

How many people with MS succeed in quitting smoking?

Because we don’t know exactly how many people with MS smoke, this is a difficult question to answer. But as I mentioned before, several studies have followed people with MS over many years, sometimes 10 years, and have reported that the people who quit do a lot better in terms of their MS, their mental health and physical health.

Is there a positive outcome for people with MS who manage to reduce their smoking?

Studies show that there is a dose-response relationship, meaning that the more you smoke the worse your health outcomes. So this suggests that reducing the amount of tobacco you smoke will be helpful. But there is no safe dose of smoking; any amount of regular smoking (daily or weekly) is likely to do some harm.

Strategies to quit smoking for people with multiple sclerosis

What are the most important barriers to quit smoking?

Studies have reported that nicotine is in the top 3 most addictive substances, together with crack cocaine and heroin. The tobacco industry is very cunning, they use a lot of tricks to get people hooked on cigarettes and make it very hard to quit. For example, they use chemicals to enhance the addictive qualities of nicotine, such as ammonia. They also use design features such as filters to get the smoke even deeper into your lungs. If you quit smoking, you will experience nicotine withdrawal effects such as irritability or headache, which generally makes you want to light another cigarette or cigar. You may also be temporarily more sensitive to pain or experience anxiety or depressive symptoms, which make you want to smoke again.

How long does the physical dependence last?

The physical withdrawal effects will become less after 3 days and are mostly gone after 2-4 weeks. Short-term nicotine withdrawal effects may sometimes even be confused with MS symptoms. Therefore, it is important to get support during this crucial phase of quitting. In the long term, quitting will be beneficial for all aspects of health.

Are there certain strategies that seem to be more successful for smoking cessation?

We know from research that you have a much better chance of quitting if you use a combination of quitting medication and counselling. It is really important you are well supported while you are quitting. I would recommend speaking with your family and carers about why it is so important for you to quit, and ask them to help you. I would also recommend speaking to your family doctor and discussing options for counselling and quitting medication. Nicotine replacement therapies include nicotine patches, chewing gum, inhalers, oral spray, or lozenges, and you can get medications such as varenicline and bupropion. Despite these therapies people often still experience some withdrawal symptoms, so it’s good to be prepared for that. There are also organisations that provide free support, such as telephone support, phone apps, etc that can help by showing you how much money you are saving and what the health benefits are. It is so important for your MS and general health to stop smoking, that I would try to active all the assistance you can think of to give yourself the best chance. Trying to quit without any help is almost always unsuccessful.

How can dopamine be released in a healthy way?

Well this depends on the person, but when I quit smoking I started running. Other people might find that something like yoga, a walk in nature, cooking, singing, or dancing distracts them when they think about smoking while they’re quitting.

What is the situation with psychological dependence and how long does it last?

You might think that smoking helps you feel less stressed or anxious. But actually, that’s a misconception, the nicotine dependence causes stress and anxiety, which you start to feel within hours of smoking your previous cigarette, which you then relieve by smoking another. So smoking actually causes this cycle of stress and stress-relief. Studies have found that feelings of anger, frustration, and irritability which are common when you quit peak within 1 week and may last 2 to 4 weeks. Quitting improves feelings of stress, anxiety and depression in the long term.

Do you have a recommendation on how to overwrite this trained associations?

All of the quitting support I have previously mentioned.

Where do people find support who want to quit smoking?

Your family doctor should be able to support you and refer you to trained councillors or psychologists. You can also contact the German Quit line: 08008313131. Remember to explain to your friends and family why it is extra important for people with MS to quit and ask them to support you.

What is your message to the ones who tried smoking cessation once or even couple of times already?

Many people try a few times before they successfully quit. It can be really hard, the tobacco companies make it as hard as possible to quit their products. But every time you try, you are one step closer to quitting. Make sure you get as much support around you as possible because almost no one can do it alone. It is never too late.

Which breakthrough in research or treatment for people with MS would you like to see in the next 5 years?

Of course I would love to see a vaccine or other strategy that will prevent the onset of MS all together.


How and where can interested people follow your research activities?

They can keep an eye on my University website


Is there anything else you would like to share with the listeners?

I want to put in context that quitting smoking and avoiding passive smoking is one part of healthy behaviour which also includes looking after your mental health, being physically active, and enjoying a healthy diet.

Many thanks to Dr. Claudia Marck for the original English interview on the important topic of smoking cessation. And for allowing me to reproduce the short form of the interview in German.

See you soon and try to make the best out of your life,

For more information and positive thoughts, subscribe to my newsletter for free.

Click here for an overview of all podcast episodes published so far.

And at many more places.

* This text contains affiliate links. This means that I get a small compensation if you buy the product recommended by me through the link. For you nothing changes in the price of the product. And it helps me to pay for the blog and to write new posts.

Teile diesen Beitrag

Ähnliche Beiträge

Portraitbild Nele Handwerker

Nele Handwerker

Blogger & Patient Advocate

I show you how to make the best of your life with MS from family to career to hobbies. Thanks to science and research, a lot is possible nowadays.

Nele Handwerker


Do you want to understand MS better?

Then get 11 impulses for a positive course as a gift and receive important information about the disease.

My favorites