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Find out the impact of smoking on diabetes and how to get help to quit.

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Diabetes affects around 600,000 Londoners and causes around 22,000 deaths every year 

A report from Diabetes UK suggests that the disease is on the rise across the UK and that by 2023, more than 10% of the London population will be diagnosed as diabetic 

There are two main types of diabetes: type 1 and type 2.

When you have type 1 diabetes, your body can’t make any insulin at all. If you have type 2 diabetes, which is the most common, it’s a bit different. The insulin you make either can’t work effectively, or you can’t produce enough of it. They are different conditions, but they’re both serious and they are both affected by smoking.. 

Read on to find out how smoking makes diabetes worse and how you can access free support to quit smoking.  


How does smoking affect diabetes?

Whether you have type 1 or type 2 diabetes, smoking makes your diabetes harder to manage as it increases your blood sugar levels and makes your body less responsive to insulin. 

If you have diabetes and you smoke, you are more likely to have serious health problems from diabetes, including: 

  • Heart disease 
  • Kidney disease 
  • Poor blood flow in the legs and feet that can lead to infections, ulcers, and possible amputation (removal of a body part by surgery, such as toes or feet)
  • Retinopathy (an eye disease that can cause blindness) 
  • Peripheral neuropathy (damaged nerves to the arms and legs that cause numbness, pain, weakness, and poor coordination) 


How does smoking affect type 1 diabetes?

Managing type 1 diabetes is challenging, and smoking can make it even harder. Since nicotine increases your blood sugar levels, if you have diabetes and smoke you often need larger doses of insulin. 

If you are diabetic and smoke you’re also more likely to suffer from cardiovascular complications such as heart attacks, strokes and circulatory problems.  

Diabetes causes serious health complications such as heart disease, kidney disease, vision loss, or an amputation (removal by surgery) of a toe, foot, or leg. If you have diabetes and smoke, you’re more likely to have complications—and worse complications—than people with diabetes who don’t smoke. 

If you’ve been diagnosed with diabetes, giving up smoking is one of the most positive things you can do to both improve your health and reduce your risks of the long-term complications associated with the condition. 


Can smoking cause type 2 diabetes?

Smoking is one of the biggest risk factors for people developing type 2 diabetes. In fact, people who smoke tobacco are 30%–40% more likely to develop type 2 diabetes than people who don’t smoke 

This is caused by the harmful chemicals found in tobacco products that interfere with your body’s cells and interrupt regular function. Smoking also causes inflammation in your body and when you inhale cigarette smoke, it causes cell damage known as oxidative stress.  

Smoking also makes it harder for your body to control blood sugar levels. Nicotine – the addictive chemical in tobacco – is known to make your body less responsive to insulin – a hormone that allows your body to use glucose for energy.   

This combination of irregular blood sugar levels and insulin resistance puts you at greater risk of developing type 2 diabetes. 

What is the impact of smoking on diabetes?

Stephen Thomas - Clinical Director, London Diabetes Clinical Network - explains how smoking makes diabetes worse and can increase of your risk of developing type 2 diabetes.

Stephen Thomas - Clinical Director, London Diabetes Clinical Network - explains how smoking makes diabetes worse and can increase of your risk of developing type 2 diabetes.

I want help to quit smoking

You can get free help from Stop Smoking London.  

We’ve helped thousands of people over the years to quit smoking and we know that everyone’s journey to giving up is different.   

Find your nearest local stop smoking service.  

Sign up for the free text messaging service here.   

Call the free Stop Smoking London Helpline.  

Access helpful guides, read success stories from ex-smokers and use free resources.  


How have other people quit smoking?

For years, people have used Nicotine Replacement Therapy (NRT), such as gums or patches, along with prescribed medications to quit smoking. 

Cigarettes contain tar, which has cancer-causing chemicals and nicotine – a highly addictive but not cancer-causing substance. When you quit smoking, your body craves nicotine, and NRT helps you to manage those cravings and withdrawal symptoms. 

Nicotine replacement products such as gums, patches, and vapes are effective tools for quitting smoking. Combining NRT or vaping with behavioural support from stop smoking services triples your chances of success. 

Finding inspiration from successful ex-smokers can also help.



If you have diabetes and you smoke, quitting smoking will benefit your health right away. Quitting smoking can help you to better manage your blood sugar levels and it also reduces the risk of long-term complications such as heart and kidney disease. 

It doesn’t matter how long you’ve been smoking or how many cigarettes you smoke, quit smoking now and you will improve your health and your finances. See how much you could save by visiting our stop smoking calculator.