Everybody has habits. Habits are defined as something that you do often and without thinking. A habit is something that is especially hard to stop doing. Habits can be good and bad.

Examples of good healthy habits might include daily exercise, drinking a sufficient volume of water and incorporating fruits and vegetables into your diet. Bad health habits may include drinking alcohol excessively, the frequent intake of fast food, not exercising and smoking.

Whether you are thinking about giving up cigarettes or you have recently quit, well done on seeking out the information you need to quit. In this article, we are going to specifically talk about what happens when you quit smoking. We know that the physical and psychological side effects when you quit smoking can be difficult to deal with but you more you understand them from the outset, the better your chances of giving up cigarettes for good.

To get started, let’s look at some of the reasons that it’s definitely a good idea to quit smoking:

  • Smoking causes more deaths than HIV, drug use, alcohol use, car accidents and firearm related incidents combined. Tobacco is the leading cause of preventable death in the world.

  • Smoking causes four out of five cases of lung cancer, and it has one of the lowest survival rates of all cancers.

  • On average, the life expectancy of a smoker is 10 years less than a nonsmoker.

  • The most recent statistics say that 20% of the world’s population are classified as smokers, with the highest prevalence of smoking in Russia and the lowest volume of smokers residing in Ethiopia.

For smokers, those statistics are easy to ignore but as we age and the number of cigarettes we have smoked continues to pile up, there is a strong chance that you could become one of these numbers.

Up until recently, I was one of those numbers partaking in a leading cause of preventable death. A teenage habit became more difficult to budge in adult life, however as someone who works in the health industry, it was becoming harder and harder to not practice what I preach.

In this article, I will talk you through what happens when you quit smoking, the motivation to stop for good and the biomarkers that I am watching as my body detoxes of nicotine.


What Are The Side Effects Of Quitting Smoking?

The side effects of quitting smoking are both physical and psychological. Each person quitting smoking will have a unique experience, however the side effects are said to peak after 1-3 days without nicotine. Your cravings and the negative side effects of quitting smoking will then begin to steadily decrease over the next 3-4 weeks.

Up until recently, smoking tobacco products was one one of my favourite hobbies, and I was very good at it. I would put away approximately 15 cigarettes per day(!) until I made the decision to quit.

As Head Of Content for LetsGetChecked, I was surrounded by all of the knowledge I needed to know that I was truly putting my health at risk, no amount of spinach, running, kombucha or steam rooms were going to undo the damage that putting on myself each day. Now, I know that the majority of people do not have access to medical advice on tap, medical data or spend each day writing health and wellness content, however, by making the choice to even read this article, you are starting to see the merits of quitting and that’s amazing, you should be proud of yourself!

Let’s talk about the side effects of stopping smoking in the hours, days and weeks of quitting so you know and can continuously monitor your improved health and keep track of the progress that you are making.

What happens in the hours, days and first week after you quit smoking?


Source: SmokeFree App, available on Google Play

Some of the most common physical side effects of quitting smoking include:

  • Feeling light-headed or dizzy
  • Headaches
  • Nausea
  • Sweating or high temperature
  • Feeling restless
  • Shaking or tremors
  • Trouble sleeping, waking at night or insomnia
  • Increased appetite
  • Cramps, gas or bloating
  • Digestive issues, most commonly constipation

Some of the most common psychological side effects of quitting smoking include:

  • Strong cravings to smoke and/or consumed by the thoughts of smoking
  • Brain fog
  • Mood changes such as anxiety or depression
  • Feeling frustrated, angry or sensitive
  • Difficulty concentrating

The literature does not lie when it says the side effects of quitting smoking will peak on days 1-3 after quitting. As the body begins the detox process, your blood sugar is likely to plummet which will lead to severe fatigue, brain fog and craving sugary snacks. Emotionally, it’s very likely that you will feel a lot more sensitive than normal and struggle to concentrate.

My advice? Make sure that once you set your quit day, you have mapped out the first following week so that you can control your stress levels, fill the week with healthy distractions and beat the cravings which will continuously nag at you, especially if stop smoking ‘cold turkey’.

Unfortunately, it’s accurate to say that a worrying percentage of the global population continues to smoke, however, with rising tax and incentives to quit smoking coming in hard and fast worldwide, the numbers are starting to look a little bit more encouraging.

In fact, the CDC reports that the number of those smoking has declined a whopping 67% since they started reporting on this topic in 1965.

There is an abundance of information out there when it comes to smoking, different methods of smoking cessation works for different people. The most important thing is that you follow through with your decision to quit.
Let’s take a look at some of the differences of ‘going cold turkey’ vs. gradually weaning yourself off cigarettes.

What Happens When You Stop Smoking? | The Cold Turkey Approach


There are numerous ways to quit smoking on the market today. Methods include everything from hypnosis, to prescription medication, nicotine replacement therapies and swapping out traditional cigarettes for e-cigarettes or vapes.

There is no right way to quit smoking. Quitting smoking in itself is a hard battle so whatever works for the quitter is the “right way.”

Some studies suggest that quitting ‘cold turkey’ increases your chances of giving up for good, while other studies suggest that gradually decreasing your intake until you are at the point of full cessation is the best method.

In one study that included 700 participants, it was found that those who quit smoking with the ‘cold turkey’ method were more successful than those who gradually stopped smoking.

In the six month follow up, researchers found that 22% of those who quit smoking ‘cold turkey’ were still cigarette free after their quit date, while only 15.5% of those who gradually cut back were still not smoking after the first six month period.

If you are going ‘cold turkey’, you will need to expect what happens when you quit smoking to be a bit more severe than a slower uphill battle, however the prospect of the long term goal being fulfilled is promising.

For instance, if you go from 20 cigarettes a day to 0 the next day, headaches, insomnia, and increased appetite and negative mood are likely.

The side effects of quitting smoking abruptly may also be more severe in those who give up ‘cold turkey’, or they may be more severe in those who are gradually quitting. The highest success rates are seen in those who visit their doctors and get the advice and support they need in their battle to end their addiction.

If you are going ‘cold turkey’, here are some of the best tips to tackle this head on:

  • Know your triggers: what makes you want to smoke?
  • Fill your calendar: if you’re always busy, you will have less time to think about smoking.
  • Have a piggy bank: for every box of cigarettes you don’t buy, put that money into a piggy bank, at the end of each week, spend that money on something specifically for you to motivate your progress.
  • Self-care is #1: Don’t attend events that will trigger smoking until you know you can handle it.
  • Preparation is key: Plan your meals, work-outs and meetups with friends so you know what’s ahead and you don’t fall into relapse.

Smoking And Hormones | What Happens?

It has been proven on numerous occasions that smoking and nicotine plays a role in, and affects neuroendocrine function.

Smoking affects a number of your hormones including:

Smoking over a substantial period of time may lead to lowered testosterone levels in males

Smoking is said to lower estrogen in females and lead to a higher volume of free testosterone in the body.

Thyroid Stimulating Hormone
Smoking can increase the function of thyroid hormones and decrease thyroid stimulating hormone. When you quit smoking, your metabolic rate is said to drop by 10%.

Smoking is associated acutely with elevated cortisol levels.

Overall, smoking has a negative impact on your hormonal health. One of the most well-documented correlations exist between smoking and cortisol.

Cortisol is your stress hormone, it triggers a fight or flight response when you perceive an external threat.

In one study, researchers sought to look at the difference between cortisol levels in smokers and non smokers over a daily period. Following this, researchers sought to monitor what happens to cortisol levels when people quit smoking.


In the first part of the study, 196 participants were asked to provide saliva samples. The participants were middle-aged men and women. Saliva samples were collected on weekdays and weekends, repeatedly throughout the day.

It was found that cortisol levels were significantly higher in smokers on weekdays and weekends. The elevation in cortisol among smokers is generally attributed to nicotine exposure.

In those who are quitting smoking, it was found that Nicotine Replacement Therapy (NRT) would greatly improve their chances. The effects of NRT on cortisol is however still unknown.

In the second part of the study, cortisol was monitored over 6 weeks of abstinence in 112 smokers treated with behavioural support and 15 mg nicotine patches.

It was found that quitting smoking leads to an immediate decline in cortisol. The decline remained steady throughout the abstinence period.

While more study needs to be concentrated on why smoking causes cortisol to increase in the first place, it still stands that the side effects of quitting smoking are not ruled by your declining cortisol levels, with the possible exception of hunger that may be stimulated by changing cortisol levels in the blood.

What Are The Symptoms Of Cortisol Imbalance?

Symptoms of high cortisol include:

  • Hypertension (high blood pressure)
  • A flushed or red face
  • Muscle pain or weakness
  • Increased thirst or dehydration
  • Urinating or having the urge to urinate more frequently than usual
  • Negative mood changes
  • Chronic fatigue
  • Osteoporosis
  • Low libido or sex drive

Symptoms of low cortisol (which is also sometimes known as Addison’s disease) include:

  • Hypotension (low blood pressure)
  • Hypoglycemia (low blood sugar)
  • Feeling tired all the time or extreme fatigue
  • Fainting
  • Weight loss and/or a decreased appetite
  • Darkening of the skin (hyperpigmentation)
  • Abdominal pain or bloating
  • Nausea
  • Diarrhea
  • Vomiting

If there isn't already a large number of good reasons to quit, think about how quitting smoking will begin to regulate your stress hormones and the positive impact this could have on both your sleep and perception of external threats. I began my bio-marker testing journey with a Cortisol Test.


A month following my efforts to quit, I will be interested to see where my cortisol levels are.

Smoking And Blood Sugar | What Happens?


One of the most dramatic side effects of quitting smoking, that I noticed was how fatigued I felt in the first week. Most people complain of insomnia, feeling jittery or waking at night.

I felt totally exhausted. This is probably relatable to many others who have just quit smoking, and the reasoning lies in the effects that smoking has on your blood sugar.

Smoking over time leads to high blood sugar levels. Often those who smoke won’t taste the sugar or fat content in foods. As your taste buds and sense of smell begins to recover, it’s very common to crave sugary snacks and drinks.

The reasoning behind this lies in the fact that your blood sugar plummets in the days after you give up smoking. I advise you to try and have some planning around what you’re going to eat in those days of severe cravings.

Quitting smoking and weight gain commonly go hand in hand but you don’t need to fall into that trap. With a little planning and know-how, you can avoid that side effect. Weight gain during the quitting period can be a large motivator for people to relapse, so it’s important to try and maintain a healthy, balanced lifestyle.

Have a sugary craving that you can’t kick?

If you have a strong urge to lock yourself in a closet and go to town on a chocolate cake, and if you can’t shake that feeling, I recommend chopping up fruit and veg that have a sweet and refreshing taste. Think yellow peppers, grapes, strawberries, cucumbers, cherry tomatoes, oranges, pineapple and mango.

Did you know that smokers are 30% to 44% more likely to develop type 2 diabetes than nonsmokers? The greater the number of cigarettes you smoke, the higher your chances are of developing type 2 diabetes.

Systematic reviews confirm that active smoking is associated with an increased risk of type 2 diabetes.

Multiple biological mechanisms for the connection between smoking and development of type 2 diabetes have been put forward, including the effects of smoking on your cortisol levels, the increased likelihood of being obsese if you are a smoker, increased chances of experiencing physiological inflammation, oxidative stress, insulin resistance and the overall increase of glucose in the blood.

If you are a regular smoker, you are more likely to experience insulin resistance, which is caused by having elevated blood sugar levels over time.

This is because:

  • Nicotine changes/develops the chemical processes in your cells, which can make it more difficult for insulin to be absorbed by the cells.
  • Nicotine has the ability to make your blood sugar level go up or down. Nicotine alters the way that your body uses glucose and fuels your cells.

According to the American Diabetes Association, there is also a significant risk of developing type 2 diabetes after you quit smoking. The increased risk of type 2 diabetes associated with smoking cessation seems to be partially mediated by weight gain.

This study suggests that individuals who quit smoking are at an increased risk of type 2 diabetes and that this risk is highest in the first 2 years after smoking cessation, but that risk declines after this point until no excess risk is observed at 12 years after cessation.

What Are The Symptoms Of Irregular Blood Sugar?

Symptoms of high blood sugar include:

  • Frequent urination
  • Increased thirst or cravings for water
  • Blurred vision or changes in eyesight
  • Feeling tired all of the time
  • Brain fog, headaches or migraines

Symptoms of low blood sugar include:

  • Hunger or an increased appetite
  • Pale or greyish skin
  • Shakiness or tremors
  • Mood changes, most commonly anxiety and irritability
  • Feeling tired all the time
  • Tingling sensation around the mouth or in the hands

Testing your blood sugar before and after you quit smoking is a great measure of integral bio-markers and could act as a great motivator in giving up smoking.

Prior to quitting smoking, we can see that my blood sugar was in a normal range. Using the Diabetes Test, I was able to see the volume of sugar molecules that stick to my red blood cells.

When I take another test in a month, it will be interesting to see if my blood sugar has gone up or down. Either way, it will certainly act as a motivator for me to keep my diet and intake of sugar cravings in check.


Smoking And C-Reactive Protein | What Happens?

C-Reactive Protein (CRP) is a protein that is produced in the liver. CRP levels rise in response to inflammation. CRP is a marker that can be used to predict heart disease, the risk for certain cancers, diabetes, obesity and inflammation related diseases.

It is well documented that CRP levels in current smokers are elevated but unrelated to the number of cigarettes smoked each day. It has also been shown that quitting smoking will lead to the reduced risk of developing inflammatory disorders, as well as heart disease.


Nicotine begins to play a significant role in your digestive system. When you stop smoking, your digestive system slows down. This can mean bloating and/or constipation. These side effects can lead to stomach pain due to pressure on the intestinal wall.

This symptoms gradually begins to subside as withdrawal symptoms lessen over 1-2 months. Make sure that you drink enough water and increase the fiber in your diet with fruit, salad, vegetables and whole grain cereals and exercise regularly to avoid digestive issues during your efforts to quit.

What Are The Symptoms Of Out Of Range C-Reactive Protein?

There are no specific symptoms of high or low C-reactive Protein in the blood due to the fact that it is not a specific test.

If symptoms are present, it ultimately comes down to the diagnosis as CRP is associated with a number of different inflammatory disorders.

However, due to the fact that smoking is known to slow down your immunity, I thought it would be worth my while to test the volume of CRP levels in my blood.

CRP is typically not detected in the blood unless inflammation is present. We can see from my CRP test that my levels fall within a normal range, however CRP has been detected.

I took a CRP test the day before I made the decision to quit. I will re-test my levels following four weeks of complete abstinence from smoking and/or NRT.


The Motivation You Need To Stop For Good

There are so many methods of motivation that you can utilize to help you quit smoking for good, but the main source of motivation is always going to come from yourself.

You are making a choice to put a halt to a habit that is killing you slowly and ending your life faster than your non-smoking friends, however, when the craving hits, it’s harder to remember that.

Trust me, I get it!

Here are some of the most useful tips I have found to work in the first week of quitting. If they could get me through it, I’m sure they will help you.

Water, water, and more water


Do you know that feeling when you wake up ‘the morning after the night before’? Maybe you had one too many wines and now the Sahara desert has come to live in your mouth and throat. This feeling of dehydration comes from the fact that your body is using all available liquid to detox alcohol from the body.

This detox process is similar when it comes to smoking. You are going to experience a whole host of weird physical and emotional side effects in the next week and your body needs to be fully equipped via hydration. Commit to three liters a day, it will help with some of the side effects and in navigating whether your increased appetite in hunger or a cigarette craving.

Healthy distractions


Focus on healthy distractions like going for a morning or evening walk, grabbing a stress ball or fidget spinner, putting more attention into your nails or honing your skills in knitting, tea drinking, making pottery. Whatever it is, putting something into your hands is a great way to distract yourself.

My morning walk to work now involves holding a peppermint tea in one hand and a bottle of water in the other. If you don’t give your opportunity to smoke, you won’t.

Positive Reinforcement


The power of positive reinforcement is well documented. If we receive praise, we are more likely to repeat the action that warranted praise.

We can also set up positive reinforcement cues for ourselves. Keep track of how much money you are saving each week and buy yourself a weekly present.

Once you become accustomed to your weekly reward, you will be less likely to fall back into the smoking trap. Self-care is more than just good nutrition, working out or going to see your physician. Self-care also comes in the form of a new candle, pair of runners, a yoga class or a hot chocolate.

Instead of focusing on what you are losing by not smoking, focus instead on what you are gaining.

Rekindling The Love For Old Hobbies


For those, like me who have been smoking for a long time, it is very possible that you have pushed some of your old hobbies to the side as smoking began to take over.

This could be anything from athletics to hobbies that you would be more likely to do inside.

For example, I used to love running but then found that I was constantly out of breath and stopped doing it. I also used to love reading but it involved sitting down inside and concentrating. Both of these activities are fantastic for relaxation in different ways, but as a smoker I didn’t make time for them.

Bring the things you love back into your daily routine. I now find that running and reading are two of my primary distractions and rekindling that love for these old hobbies has acted as a great motivator.

Spending Time Around People Who Don’t Smoke


You don’t need to unfriend anyone because of their habits, think about all of the times you have coaxed your non-smoker friends to go outside with you when you want to light up.

I would however recommend that you steer clear of triggers for the first full week of not smoking. That can include places, foods, drinks and of course people.

If you have a friend that you always meet up for coffee and a few cigarettes, it could be particularly hard during the first week to say no. As the friend who has enabled my quitting friends by giving them their “one last cigarette”, I don’t think the power of triggers can be over-emphasized.

Spend time around your pals who don’t smoke, do as many activities as possible. You’ll soon start to feel the positive side effects of quitting smoking.

You won’t smell like an ashtray, your energy levels will soar and you will begin to feel the effects of all of your healthy habits outside of smoking beginning to work.

In the next month, I will be documenting my progress as well as testing my bio-markers to show how the side effects of quitting smoking are reflected in both my blood and brain!

Do you have a quitting smoking that you would like to share? Maybe you would like to reach out to speak to us about the steps that you can take to begin your health journey? Reach out and we will do what we can to help!

Read: What Are The Effects Of Alcohol On Your Health?

Written By Hannah Kingston | Approved By Medical Director Dr. Dominic Rowley