12A.4 What makes an effective health warning?

Guidelines from the World Health Organization (WHO) recommend using a range of health warnings to increase the likelihood of impact.¹ Although some warnings may appear more effective in specific tests compared to others, using a range of warnings provides comprehensive coverage of the important messages and can be used in rotation to decrease the effects of wear-out (see Section 12A.3.9).¹

Research on the effects of health warnings on cigarettes can be divided into research on the content of the warnings and research on the form these warnings should take.²

12A.4.1 What content should warnings cover?

Warnings need to fully inform consumers about the health risks of smoking.¹ It is important that people understand not just the increased risk of disease, but also what contracting a disease would mean to the longevity and quality of their life. Conveying such information is not straightforward. People who smoke tend to bring to these warnings their own ‘sender–receiver’ relationship made up of preconceived knowledge and ideas, as well as self-protective and self-exempting beliefs and reactions. For example, while people who smoke generally know that tobacco use is harmful, they tend to underestimate the health risks to themselves and often perceive others who smoke to be at greater risk for disease than themselves (see Section 3.34).

Guidelines on content from major reports

World Health Organization guidelines for the regulation of packaging and labelling of tobacco products, recommend that warning content should aim to increase knowledge of:¹

• the harmful effects on health,
• the addictive nature of tobacco,
• the impact of tobacco use on significant others,
• the adverse social and economic outcomes, and
• strategies for cessation.

More information about WHO guidelines on warning attributes is presented in Section 12A.4.3 below.

A review of theories and evidence, largely from social psychology,³ suggests that warnings are more likely to be effective in increasing understanding of tobacco-related risk if they:

• consider the attitudes of the consumers who use tobacco products
• combine information that is likely to invoke strong fear responses with information about how risk can be avoided
• convey the social and physical consequence of negative health effects
• promote discussion about smoking among friends and family
• confront self-exempting beliefs
• are presented in a way that minimises wear-out (the inevitable process by which repeated exposure gradually diminishes effect).

A suite of health warnings needs to:

• cover a broad range of health effects
• emphasise morbidity as well as mortality
• cover the same health effect from the points of view of people of different ages and at different stages of smoking uptake and cessation⁴
• use language that is clear, strong and direct³
• explain how the effect occurs in concrete terms
• paint a picture of what life would feel like should a disease be contracted
• be frequently rotated and updated to include new images and information that explores different aspects of the particular risk.

Figure 12A.4.1 shows an example from the 2025 Australia graphic health warnings for roll-your-own pouches.⁵ Elements described above can be seen in this warning, including morbidity (‘lose your voice’ and ‘breathe through a hole in your neck’), clear strong and direct language, images designed to provoke strong fear responses, explanation of how the effect occurs (hidden flap message), social (loss of voice) as well as physical consequences and indication of how to avoid risk (Quitline number).

Heath warnings with both graphic and ‘lived experience’ elements are generally more effective than those that use symbolic content.⁶ Testimonial warnings using images of real people and factual information about health effects can elicit intentions to quit.^7,8 Warnings with information about toxic constituents of tobacco smoke on the packs can increase knowledge of toxic constituents as well as reinforce the effects of health warnings about specific health outcomes.⁹

The optimal accompanying text for pictorial warnings has been investigated.^7,10 A study from the US⁷ examined the effects of different types of accompanying text that may contribute to the effectiveness of images in testimonial warnings. Effectiveness was measured by testing emotional responses, engagement behavioural intentions and quit attempts. There was little evidence that adding identifiers (name, age etc.) or the explanatory statements (in either testimonial or non-testimonial form) enhanced the effectiveness of testimonial warnings. But they authors cautioned that this result could be attributable to the context (the US) and research methodology.⁷

A study of the effectiveness of different message themes for health warnings in China compared (1) harm to oneself from using cigarettes, (2) harming family or children with secondhand smoke, (3) reinforcing compliance with existing smoke-free policies and (4) anticigarette gift giving practices.¹¹ Warnings were rated by participants on the basis of attributes such as credibility, raising awareness of health harms of smoking and raising thoughts of quitting. While the theme of harming family or children with secondhand smoke had the highest rating, all these themes were considered to be effective.¹¹

Gain or loss framing

Warnings framed as losses from smoking can be complemented by messages framed as benefits of quitting. One study¹⁰ compared the effects of warning labels that stress short-term losses of smoking as well as labels that stress both short- and long-term benefits from quitting. Findings show enhanced effects of gain over loss frames and short-term over long-term consequences on warning labels for attitudes and intentions.¹⁰ Gain-framed messages showed stronger effects on intentions to quit smoking than loss-framed messages when warning labels concerned short-term outcomes. An eye tracking study has also tested the visual attention, self-reported avoidance, and reactance to gain- and loss-frames.¹² Higher self-reported avoidance and reactance were observed for loss-framed warnings, indicating higher-level engagement with warnings.

New knowledge

Roll-out of warnings that contain new knowledge, such as conditions that most people do not know are caused by smoking, can be effective. One study has found that graphic health warnings that enhance knowledge may discourage smoking both directly and indirectly through the worry elicited by them.¹³ There is experimental evidence that warnings about tobacco product manipulations may be effective in Australia. Warnings about misleading product attributes (including filter ventilation, menthol, and roll-your-own tobacco) elicited concern when inhaling smoke, knowledge of product manipulation and industry-centric negative emotional responses in Australia adults who smoke.¹⁴

Attributions

A study from China has shown that attribution of messages to credible health organisations can increase the effectiveness of the warnings. Warnings attributed to the WHO and China’s Center for Disease Control were considered more credible and more effective at motivation people to quit or never start smoking.¹⁵ However, a study in the US found no evidence that adding FDA as the source can boost credibility judgments, at least in the short term.¹⁶

12A.4.2 What form should warnings take?

Major reports have been produced in Canada,^17-23 Australia,^24-30 Europe,³¹ New Zealand,^32,33 the US,³⁴ and elsewhere to guide the design of health warnings.^35,36

Wording matters

Comprehension and impact of warnings is greatly increased if they are expressed in clear, simple language.^21,28,29,37 Messages that depict health risks in a vivid and emotionally arousing manner are likely to be most effective.³⁸

Health literacy plays an important role in influencing how people who smoke respond to different risk messages. Analysis of older text warnings on 1990s cigarette packaging in the US indicates that comprehending them requires college-level education,³⁹ greatly reducing usefulness with young people, less educated people and people with poorer reading skills. One study in the early 1990s by the Centre for Behaviour Research in Cancer in Australia identified a number of risk-related words which many adolescents poorly understand and which should be avoided in warnings messages.²⁴ A more recent study found that factual messages produced higher perceived risk and strong expectations for quitting amongst persons with high health literacy, while, emotional messages produced higher perceived risk and stronger expectations for quitting among people who smoke with lower health literacy.³⁷

Size matters

Size can refer to the size of the font of the message or the size of any picture or the amount of space allocated to the warning. It is likely that all elements of size are important.

Several studies have established that larger font size is more effective than smaller font size.^22,24,40,41 Eye tracking studies of youth observing cigarette print advertisements in the US indicated that adolescents paid scant attention to the very small warnings on advertisements required in the mid-1980s.⁴²

Underpinned by social psychological theory,^3,43 a number of evidence reviews^36,44 and experimental studies^{22-24,33,45-47} suggest that larger warnings are associated with greater appreciation and acceptance of risk. A series of studies conducted by Environics Research company for the Canadian Cancer Society in June 2006 similarly found that warnings sized at 75% of the front of the pack would be more effective than those sized 50 or 60%.¹⁹ Studies from Mexico and India also indicate the importance of larger warning size in enhancing understanding, reducing willingness to purchase products and motivation to quit.^48,49 Post-implementation research also confirms that increased warning size (at least up to 50% of the front surface), increases warning effectiveness.^19,25,40,50

Research undertaken for the Canadian Government²² to guide the design of warnings implemented in 2012 found that health warnings occupying 75% of the pack were more effective than warnings occupying 50% of the pack in conveying information about the health risks of smoking. The study examined a total of 38 effectiveness indicators, grouped into seven sets:

1. Perceived communication impact (5 indicators)

2. Personal persuasiveness (1)

3. Persuasiveness associated with six social styles of people who smoke (6)

4. Image of people who smoke (12)

5. Product image (9)

6. Emotional impact (4)

7. Packaging attractiveness (1)

Two sets of indicators were less sensitive to warning size increase: smoker image (personality traits) and product image (cigarette attributes). These image indicators required at least option C (90%) in order to generate significant effects, but these effects remained small even with option D (100%) when contrasted with current scenario A (50%). Findings suggest that while increasing the size of warnings on cigarette packages improves communication impact, increased size is not nearly as effective in negatively affecting the image of people who smoke or perception of cigarette product attributes.

Graphic elements matter

Font size, headings and layout are important for aiding consumer comprehension.²

Two studies have shown that people who smoke prefer health warnings to appear in a boxed section, although the reasons for this are currently unexplored.^32 33 Full-colour warnings capture attention for longer than black-and-white warnings among both youth and adults who smoke.⁵¹ Contrasting colours such as black lettering on a white background are the easiest to read and comprehend on cigarette packs.^24,52 The background to text can serve to focus more or less attention on the text compared to the graphic component of health warnings.^28,29

Tobacco company research has indicated that graphic elements such as borders and background colours behind text can make packs attention-grabbing and appealing.⁵³ One review found that yellow most quickly and effectively seizes and holds consumers’ attention and signals warning or danger, while white connotes health and safety. Using black text on a bright contrasting background colour, particularly yellow, attracts consumers’ attention to the message. When examining the role of colours in increasing the effectiveness of health warnings, one study from Mexico has found that yellow text on a black background was more informative and motivating to quit compared with black text on a yellow background.⁴⁸ The authors suggest that further research should examine whether the effects of text and background colours vary across sociocultural contexts for which different colours can have different meanings.⁴⁸

Placement matters

People who smoke tend to have the front of the pack facing them rather than the back each time they remove a cigarette for smoking. Australian research conducted prior to the introduction of graphic health warnings in 2006 found that over 90% of packs displayed in public venues (mainly café tables) were front up.⁵⁴ Experimental work, including eye-tracking studies, has also shown that the top of the front is likely to have greater impact than the bottom of the front.^12,24 People who smoke show better recall for warnings that appear on the front, compared to the side of packages.^17,24,32,47 Few of those who smoke have cited packages as a source of information where warnings appeared on the side of the pack.^55,56

Research found that the 2006 Australian graphic warnings, which averaged more than 50% of the two main sides (30% of the front and 90% of the back), had weaker effects than the Canadian warnings, which had 50% of both sides dedicated to warnings, suggesting that the back of the pack is less effective than the front, presumably because material on the front is noticed more often.⁵⁷ The 2018 government sponsored survey on the graphic health warnings introduced in Australia in 2012 found that over half (52%) of people who smoke and recent quitters learned about the health harms of tobacco products from the written warnings on the front of the pack, compared to the back of the pack (37%) or the side of the pack (29%).³⁰

A Philip Morris document also highlights the importance of positioning on the front of packages:

 ‘Government required warnings placed on the largest packaging panel, often called the front and/or back, are the biggest marketing threat to all of us in Asia...’⁵⁸.

Pictures work best

Health warnings with pictures are more likely to draw attention, result in greater information processing and improve memory for the health message.⁴⁴ A major review notes:⁴⁴

‘Experimental research on cigarette warnings has also found that picture-based warnings are more likely to be rated as effective than text-only warnings on a range of outcomes, including as a deterrent for new smokers and as a means to increase cessation among current smokers.’⁴⁴

The increased effectiveness of pictorial compared to text-only warnings has been observed in a range of different countries and regions^59-62 including warnings for cigarillos⁶³ and waterpipe tobacco.⁶⁴ Pictorial warnings have also been demonstrated to be effective for adolescents.^61,65,66 They can be particularly effective in increasing knowledge and motivation among priority groups, such as those with low incomes,⁶⁷ impaired literacy⁶⁸ or numeracy skills,⁶⁹ people with depressive symptoms⁷⁰ and First Nations peoples.^71,72

Graphic warnings may be more effective than text-only warning as they lead to more frequent and deeper processing of warning information.^57,73-77 People who smoke place lower value on cigarettes with graphic health warnings than with text-based warnings.^78,79 This is supported by some experimental research comparing warnings of the same size and theme but differing in presentation.^80,81 Eye-tracking research has shown greater visual attention, avoidance and reactance to pictorial versus text-only warnings.¹² Non-photograph warnings with hyper-realistic illustrative images, such as those use in the proposed graphic health warnings for the US, have also been effective in pre-market testing.⁸²

Focus group research in Australia indicated that people who smoke were much less likely to be able to avoid the image than the text-based component of the proposed new health warnings. Eye tracking research conducted in 2018 on Australia’s graphic health warnings (2012) found that pictorial components garnered the highest level of attention being the area where participants first looked and looked at for longest.³⁰ Among people who smoke, the front graphic image area was the first area most commonly looked at (72%); followed by the back graphic image area (14%) and then the front top warning message area (14%). Among those who do not smoke, the front graphic image area was the first health warning area most commonly looked at (93%); followed by the front top warning message area (7%).

A study comparing the reactions of Chinese people who smoke to pictorial warnings with the current text-based warnings indicated that people who smoke were about four-times more likely to report thinking about quitting when confronted with pictorial warnings than with packs bearing text warnings, and about four times less likely to offer cigarettes to others as gifts if these were packaged with strong health warnings.⁸³ However, a 2024 study found the graphic health warnings did not directly influence intentions to gift cigarettes and noted that this practice remains a public health problem in China.⁸⁴

Following the introduction of pictorial health warnings in Canada in the year 2000, more than 90% of people who smoke reported noticing the change. Forty-four per cent of those who smoke said the new warnings increased their motivation to quit. In a study conducted for the government in Canada,⁸⁵ more than one-third of people who previously smoked indicated that warning labels had influenced their decision to quit. In a survey of Canadians who previously smoked but had quit in the three years up to October 2001, those who had quit after the introduction of the health warnings were 2.8 times more likely to cite the warning labels as an influence on their quitting than those who quit before their introduction.⁸⁶

In countries with large pictorial warnings such as Australia, Thailand, and Uruguay, more than 85% of people who smoke cite packages as a source of health information.³⁶ One study has found that using a pictorial image on the back of the pack (illustrating the same health consequence, with a different execution than on the front) reduced willingness to buy a pack. This approach also increased the perception of participants that graphic health warnings were informative and motivating to quit.⁴⁸

Graphic health warnings also appear to have a greater impact on young people than text-based warnings.⁸⁷ Studies of early text-based warnings in the US⁸⁸ and Australia⁸⁹ indicated limited impact on young people. Studies examining the impact of text-only warnings in the UK in 2008⁹⁰ found that these did help to communicate the dangers associated with smoking and prompted a small number of people who smoke to forgo cigarettes and take action to avoid warnings. However, the depth of processing (thinking about or discussing the meaning of the warnings) was limited and the text warnings were relatively ineffective among young people who smoke. In Canada by contrast, six years after their introduction, more than 90% of Canadian young people agreed that picture warnings on Canadian packages provided them with ‘important information about the health effects of smoking’, ‘are accurate’ and ‘made smoking seem less attractive’.²⁰ Graphic warnings in Australia also appear to have had a much more significant impact on young people⁹¹—see Section 12A.5.1. Adolescents in the US aged 11–13, who were exposed to graphic warnings and text only warnings, accurately recalled pictorial warnings more often than text-only warnings (82% vs. 19%).⁶¹ Recognition of warnings was also higher for pictorial than text-only warnings (82% vs. 34%) and pictorial warnings drew greater attention and elicited greater negative emotional reactions.⁶¹ A systematic review found that graphic health warnings on tobacco products are effective across a wide range of tobacco-related outcomes among young people.⁶⁶

Graphic warnings depicting short term effects of smoking may be more effective than those depicting long term effects of smoking. One study examined the emotions generated by warnings depicting short term health outcomes compared to long term health outcomes, to identify common features among the most effective warnings. Warnings that featured more immediate health outcomes elicited much stronger negative emotions from both young people who smoke and susceptible non-smokers, compared to warnings about long-term health outcomes.⁹²

Potential adverse outcomes of graphic health warnings?

The tobacco industry have suggested that negative reactions to the pictures in health warnings would reduce the effectiveness of these warnings.⁹³ However, studies on attitudes of Americans who smoke to text-only warnings compared with graphic health warnings^80,81 have shown stronger negative attitudes (e.g. greater fear and disgust) to the graphic warnings, without signs of defensive reactions,⁹⁴ which predicts a greater likelihood of quitting.^80,81,95

Warning label disparagement among people who smoke indicates greater warning relevance and processing and does not undermine cessation efforts.⁹⁶ Researchers assessed the relationship between one form of warning label disparagement, the frequency of making fun of health warning labels, and subsequent cessation attempts.⁹⁶ The study analysed data on adults who smoke from Australia, Canada, Mexico and the US between 2012-2014. Between 24%–31% of these people reported making fun of the warnings at least once in the past month in each country, across all waves. This type of health warning disparagement was an independent predictor of subsequent cessation attempts in all countries except the US.⁸⁰ Even avoidance of health warnings does not predict a lower likelihood of quitting; indeed, there is evidence that it may actually be associated with increased quitting^57,97 as higher levels of negative emotional reaction to graphic health warning labels have a positive association with quit intentions.

Context of the pack matters

Warnings need to be on a pre-specified background (e.g. white for black text), otherwise companies can effectively blend the warning into the design of the pack.⁹⁸ People who smoke recall warnings more effectively on mock packets with a plain background than they do on highly stylised cigarette packets.^46,99-101 This strongly suggests that plain packaging would increase the effectiveness of health warnings—see InDepth 11A Packaging as promotion: Evidence for and effects of plain packaging.

12A.4.3 Recommendations from the World Health Organization

In 2013, the World Health Organization (WHO) published evidence-based guidelines on the design of effective health warnings for tobacco packaging.¹ Below is a summary of these recommendations.

Warning location should be:

• on the front and back of the pack, or on all main faces of the package
• on the principal display areas, particularly at the top
• in a position in which normal opening of the pack does not damage or conceal the text or image.

Warning size should be:

• 50% or more, but no less than 30% of the principal display areas
• parties should consider using greater than 50% coverage.

Pictures and pictorial elements:

• may be used as there is evidence that they are more effective than text only warnings
• should be mandated to be culturally appropriate
• should be in full colour
• parties should obtain, where possible, ownership of full copyright of these images

Use of colour:

• full colour should be used to increase the overall noticeability of pictures
• contrasting colours should be selected for the background of the text to enhance noticeability.

Rotation (varying  warnings over time):

• health warnings should be rotating as changes are associated with increased effectiveness
• parties should establish two or more sets of warnings and specify alternating specific periods, such as every 12-36 months
• parties should require that warning series be printed so that each appears on an equal number of retail packages (for each brand within a family and for each pack size and type).

Message content:

• should use a range of different warnings and messages to increases impact
• should address issues such as health risks, impact of smoke exposure, advice on cessation, addiction, adverse economic and social outcomes, and the impact of tobacco use on significant others
• should contain information on relevant constituents and emissions, such as cancer-causing chemicals
• should not make statements that might imply that one brand is less harmful than another
• should be presented in simple, clear and concise language that is culturally appropriate
• can use various formats, such as testimonials, positive and supportive information
• can aim to elicit negative emotions such as fear, as evidence suggest this is effective
• can include information designed to increase motivation and confidence for cessation
• should provide advice on cessation and sources of cessation help such as Quitline contact details
• if required, should provide a source attribution statement specifying a credible source such as a national health authority.

Other:

• parties should consider designing warnings that target subgroups such as youth
• parties should consider premarket testing for effectiveness.

Test your knowledge

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