Quitting smoking: every method and its real effectiveness according to science

Quitting smoking is one of the best decisions you can make for your health, but it is also one of the hardest. The reason is physiological: nicotine creates a strong dependence, comparable to that of other addictive substances. The brain gets used to regular intake and demands its dose, which explains the irritability, anxiety and intense cravings felt when stopping. The good news, highlighted by both the World Health Organization (WHO) and the UK's NHS, is that the method you choose changes everything: a well-supported smoker substantially increases their chances of success compared with someone relying on willpower alone. This guide reviews, in a neutral way, all the major methods and what science really says about them.

Quitting by willpower alone: common but weak on its own

This is the most widespread method: deciding to stop overnight, with no help. It has the advantage of being free and immediate, and some people manage it. But the data are clear: without support or treatment, the one-year success rate is generally around 3 to 7%. In other words, more than nine attempts out of ten fail. This low figure is not a question of lacking motivation, but of physical dependence: willpower alone does not cancel out nicotine withdrawal. Understanding this is essential to avoid feeling guilty after a relapse and to consider, if needed, appropriate support.

Nicotine replacement therapy: a well-established effectiveness

Nicotine replacement therapies (patch, gum, lozenge, mouth spray, inhalator) deliver nicotine without the smoke or the thousands of toxic substances produced by combustion. They reduce withdrawal while you break the habit. According to Cochrane reviews, the world reference for synthesising studies, they increase the chances of quitting by about 50 to 60% compared with placebo. One important point: combining a patch (which releases nicotine continuously) with a fast-acting form (gum, spray, lozenge) for sudden cravings is more effective than a single form. Side effects do occur but remain generally mild: skin irritation under the patch, hiccups or mouth irritation with the gum. Available without prescription, they are recommended by health authorities such as the NHS and the US Surgeon General.

Varenicline: among the most effective treatments

Varenicline (marketed notably as Champix, or Chantix) acts on the brain's nicotine receptors, reducing both withdrawal and the pleasure linked to cigarettes. According to Cochrane reviews, it is among the most effective medicines for quitting smoking, with success rates roughly two to three times those of placebo. It is taken on prescription, under medical supervision. Side effects are possible: frequent nausea, vivid dreams or sleep disturbances. The doctor assesses the benefits and precautions on a case-by-case basis, particularly for people with specific medical histories.

Bupropion and cytisine: two other medicinal options

Bupropion (often known as Zyban) is a quit-smoking medicine that, according to Cochrane, increases the chances of success by about 1.6 times compared with placebo. It is also taken on prescription. Cytisine deserves particular attention: of plant origin and low cost, used for decades in Eastern Europe, it has proven effective in recent clinical trials, with results judged comparable to those of varenicline. Its low cost makes it a promising option for widening access to an effective treatment, where it is available.

The e-cigarette: now a high level of evidence

Long debated, the e-cigarette was the subject of a major update of the Cochrane review in 2024. Its conclusion, based on a high level of evidence, is that the nicotine e-cigarette helps people stop smoking more than conventional nicotine replacement therapies. This is an important finding for smokers who have not succeeded with other methods. That said, vaping is not risk-free: the scientific hindsight on very long-term effects remains limited, and it is clearly not recommended for non-smokers, especially young people. The NHS includes it as a quitting aid while stressing that it is aimed at smokers trying to quit, not at the general public.

Behavioural support: a multiplying effect

No method works in isolation. Behavioural support — cognitive behavioural therapy (CBT), telephone helplines (quitlines), pharmacy consultations, tracking apps — clearly improves outcomes. According to the WHO, support doubles the effect of a treatment when combined with it. It helps you anticipate risky situations, manage stress differently and persevere over time. This is one of the most robust findings of research: it is not only what you take, but also being supported, that makes the difference.

Methods with insufficient evidence: to be said honestly

Some approaches are popular but poorly supported. For hypnosis and acupuncture, the Cochrane reviews conclude there is no solid evidence of effectiveness for quitting smoking: they are not dangerous, but nothing shows they genuinely help beyond a placebo effect. The well-known Allen Carr method, based on reading and deconstructing the beliefs linked to cigarettes, rests on still limited but fairly encouraging evidence according to a few studies. Honesty requires saying so: these methods may suit some people, but they do not rest on the same level of evidence as the validated treatments.

Abrupt or gradual quitting: it makes little difference, the data say

Should you stop all at once or cut down gradually? The question often divides opinion, but the scientific answer is reassuring: according to Cochrane, the success rates are similar between abrupt and gradual quitting. The key is therefore not speed, but setting a date, sticking to it and relying on effective help. Everyone can choose the formula that suits them best without fearing they will reduce their chances.

The verdict: combine treatment and support

In the end, the hierarchy that emerges from the data is clear. The most effective options are a treatment (varenicline or a combination of nicotine replacements) or a nicotine e-cigarette for smokers who are struggling — all of it combined with behavioural support. Pairing a medicine or replacement with support substantially increases the chances compared with willpower alone. Here is a summary of how effective each method is:

• Willpower alone: low effectiveness unsupported (about 3 to 7% at one year).
• Nicotine replacement therapy: +50 to 60% vs placebo; even better combining patch and a fast-acting form.
• Varenicline (Champix): among the most effective (about 2 to 3 times placebo), on prescription.
• Bupropion (Zyban): about 1.6 times placebo, on prescription.
• Cytisine: plant-based and low cost, comparable to varenicline according to recent trials.
• Nicotine e-cigarette: more effective than replacements (high evidence, Cochrane 2024), but not risk-free.
• Behavioural support: doubles the effect of a treatment when combined with it.
• Hypnosis, acupuncture: no solid evidence.
• Allen Carr method: limited but encouraging evidence.

Disclaimer: this article provides general information and is in no way a substitute for personalised medical advice. Every situation is different, and some methods carry precautions or contraindications. Before starting a treatment, consult a doctor or pharmacist, who can guide you toward the most suitable solution. In France, the public service Tabac Info Service can be reached on 39 89 for free support; in other countries, contact your national quitline.

The most decisive factor is not the perfect method, but combining effective support with a genuine decision to quit.