How Health-Focused Climate Messages Influence Attitudes & Behaviour

Short-Term vs. Long-Term Attitude and Behavior Changes

• Immediate Effects: Most studies find that framing climate change as a health issue can immediately increase public engagement, concern, and support for action. For example, a U.S. national experiment by Kotcher et al. (2018) found that reading about the health impacts of global warming produced small-to-moderate short-term increases in participants’ climate change engagement (e.g. greater risk perception, worry, and issue importance) (How Americans Respond to Information About Global Warming's Health Impacts: Evidence From a National Survey Experiment - PubMed). Similarly, in a 2021 conjoint experiment, messages emphasizing how climate change harms health boosted people’s willingness to take action (such as contacting elected officials) – especially when paired with information about solutions and norms (see Feldman et al. 2021 below) (Study Identifies Messages Most Likely to Inspire Americans to Act on Climate Change and Health).
• Persistence Over Time: Evidence on long-term effects is more limited, but there are indications that some attitude changes endure beyond the initial exposure. In Kotcher et al.’s longitudinal study, many of the increases in climate change concern and affect persisted when participants were surveyed 2–3 weeks later (How Americans Respond to Information About Global Warming's Health Impacts: Evidence From a National Survey Experiment - PubMed) (How Americans Respond to Information About Global Warming's Health Impacts: Evidence From a National Survey Experiment - PubMed). In other words, people retained some of the heightened concern from health-based messages for at least a few weeks after the intervention. (Truly long-term impacts beyond a few weeks have not been widely studied, so it’s unclear if these attitude changes last months or years without reinforcement.)
• Behavioral Intentions: Health-framed messages can also spur intentions to act in the short term. Feldman et al. (2021) observed that the most effective health+climate messages (those combining personal health threat, solution benefits, and a call-to-action) significantly increased participants’ self-reported motivation to advocate for climate solutions immediately after exposure (Study Identifies Messages Most Likely to Inspire Americans to Act on Climate Change and Health) (Study Identifies Messages Most Likely to Inspire Americans to Act on Climate Change and Health). Likewise, a 2022 U.S. experiment by Maibach and colleagues found that health-focused climate messages (especially when they identified opponents; see below) led to higher policy support and willingness to engage in advocacy right after the message (Calling attention to opponents of climate action in climate and health messaging - The Lancet Planetary Health) (Calling attention to opponents of climate action in climate and health messaging - The Lancet Planetary Health). However, whether these translate into actual long-term behavior changes (e.g. sustained political action or lifestyle changes) is still an open question, as most studies measure intentions or attitudes in the moment.

Differences Across Demographic and Ideological Groups

• Political Ideology: Reactions to health-framed climate messages often vary by political orientation. Several studies indicate that conservatives can be positively influenced by health messaging – but with important caveats:
  • In Kotcher et al. (2018)’s U.S. experiment, the strongest gains in engagement were among participants who were politically moderate or moderately conservative, suggesting health impacts made climate change more salient for some right-leaning individuals (How Americans Respond to Information About Global Warming's Health Impacts: Evidence From a National Survey Experiment - PubMed). Notably, this framing helped narrow the usual climate opinion gap between liberals and conservatives in the short term.
  • Unconcerned audiences: A large 5-country study (China, Germany, India, UK, USA) by Dasandi et al. (2022) found health-focused messages particularly effective for people previously unconcerned about climate change. Among these less-engaged individuals – a group that skews conservative in the U.S. – a health frame significantly increased support for climate policies (whereas an environmental frame had little effect or even backfired for them) (Positive, Global, and Health or Environment Framing Bolsters Public Support for Climate Policies). This indicates health messaging can win over skeptics more than other frames, at least in the immediate term.
  • On the other hand, strong partisanship can mediate these effects. Chu & Yang (2020) conducted a U.S. survey experiment and found that a public-health frame actually increased ideological polarization compared to an economic frame ( Their Economy and Our Health: Communicating Climate Change to the Divided American Public - PMC ). In their study, liberal participants’ climate risk perceptions rose with a health message, but conservative participants became less supportive, widening the liberal–conservative gap ( Their Economy and Our Health: Communicating Climate Change to the Divided American Public - PMC ). This suggests that if a health message challenges strongly held beliefs, some conservatives may dismiss it (a possible motivated skepticism effect).
  • Reducing polarization: Recent research shows ways to make health messages resonate across the spectrum. Maibach et al. (2023) tested climate-health messages delivered by trusted health professionals in the U.S., with some messages also naming villains (like fossil fuel lobbyists or opposed politicians) as blockers of climate action. They found that including such opponents increased message effectiveness among conservatives and liberals alike – boosting policy support and personal advocacy intent in all groups (Calling attention to opponents of climate action in climate and health messaging - The Lancet Planetary Health) (Calling attention to opponents of climate action in climate and health messaging - The Lancet Planetary Health). In fact, the health messages that “called out” opponents yielded the largest attitudinal gains among conservative participants, thereby reducing partisan polarization on climate issues (Calling attention to opponents of climate action in climate and health messaging - The Lancet Planetary Health). This highlights that framing climate change as a health threat and a collective challenge (with identifiable wrongdoers) can unite people who normally disagree.
• Age Differences: Research to date has not found strong systematic differences by age in response to health-based climate communication. For example, in the multi-country conjoint experiment (Dasandi et al. 2022), the effect of health framing on climate policy support was consistent across age groups – younger and older adults were similarly persuaded by health messages (no significant interaction of age was detected) (Positive, Global, and Health or Environment Framing Bolsters Public Support for Climate Policies). One reason may be that health threats (e.g. disease, extreme heat, air quality) are universally relevant, albeit different age groups might find different health risks salient. (It’s worth noting that young people overall tend to be more concerned about climate change to begin with, but current studies suggest that, when presented with health-impact information, young and old alike show increased concern.)
• Gender: Gender does not appear to dramatically alter receptiveness to climate-health messaging. In experimental studies that report subgroup analyses, men and women respond similarly to health frames. For instance, Dasandi et al. (2022) found no significant gender differences – the health message boost in climate policy support was seen in both men and women (Positive, Global, and Health or Environment Framing Bolsters Public Support for Climate Policies). This implies that the public health framing has broad appeal regardless of gender. (Some surveys find women express slightly higher worry about climate-health risks in general, but in terms of persuasive impact of messaging, both genders are comparably influenced according to available studies.)
• Other Groups: The effectiveness of health-oriented climate messages has been observed across various countries and cultures, suggesting it is not confined to one region. Studies in high-income nations (US, UK, Germany) as well as in China and India all report positive impacts of health framing on climate attitudes (Positive, Global, and Health or Environment Framing Bolsters Public Support for Climate Policies) (Positive, Global, and Health or Environment Framing Bolsters Public Support for Climate Policies). Education level and income have not consistently shown strong moderating effects on these messaging outcomes either (Positive, Global, and Health or Environment Framing Bolsters Public Support for Climate Policies) – meaning that individuals across the socioeconomic and educational spectrum tend to find health impacts persuasive. Overall, framing climate change around human health tends to make the issue more personal and immediate for diverse audiences, which can cut through political or cultural divides in many (though not all) cases.

Study Highlights and Evidence Details

Below is a summary of recent, high-quality studies (post-2020 where possible) that examined health-framed climate change communications. Each entry notes the location, study design, and key findings regarding attitudinal/behavioral change and group differences:

• Kotcher et al. (2018) – United States – Two-wave survey experiment (randomized) exposing 2,254 adults to short essays on eight health impacts of climate change (e.g. heat-related illness, infectious diseases) versus a no-information control. Findings: Health impact information increased climate change worry, risk perceptions, and issue engagement in the treatment group relative to control (How Americans Respond to Information About Global Warming's Health Impacts: Evidence From a National Survey Experiment - PubMed). These changes were statistically significant but modest in size. Crucially, many effects persisted at a follow-up 2–3 weeks later, indicating some long-term retention of heightened concern (How Americans Respond to Information About Global Warming's Health Impacts: Evidence From a National Survey Experiment - PubMed). The biggest responses were observed among moderate and moderately conservative participants, who showed greater increases in concern, suggesting the health frame resonated especially with those not already alarmed (How Americans Respond to Information About Global Warming's Health Impacts: Evidence From a National Survey Experiment - PubMed). (Citation: GeoHealth, 2(9): 262–275 (How Americans Respond to Information About Global Warming's Health Impacts: Evidence From a National Survey Experiment - PubMed))
• Feldman, Kotcher et al. (2021) – United States – Conjoint survey experiment with a nationally representative sample (~1,200 U.S. adults). This study tested 360 different message combinations about climate and health, varying: (1) the type of health impact emphasized (e.g. air quality, vector-borne disease, extreme heat), (2) the solution offered (e.g. clean energy improving health, sustainable food, etc.), and (3) the call-to-action appeal (e.g. a normative appeal “others are taking action” vs. just facts). Findings: The most effective messages at motivating climate action intentions were those that combined a concrete health threat + a tangible solution + a social norm cue (Study Identifies Messages Most Likely to Inspire Americans to Act on Climate Change and Health). For instance, a message noting that air pollution from fossil fuels harms people’s health, explaining that clean energy would improve health, and highlighting that a majority support this solution was especially compelling (Study Identifies Messages Most Likely to Inspire Americans to Act on Climate Change and Health) (Study Identifies Messages Most Likely to Inspire Americans to Act on Climate Change and Health). Such multi-faceted health messages significantly increased participants’ willingness to contact their members of Congress about climate policy (the main behavioral intention measure) compared to other frames. This effect was robust across demographic groups; no large differences by age or gender were reported, implying broad effectiveness in the general U.S. public. (Citation: “Advocacy messages about climate and health are more effective when they include information about risks, solutions, and a normative appeal: evidence from a conjoint experiment,” Journal of Climate Change and Health 3 (2021) 100030 (Study Identifies Messages Most Likely to Inspire Americans to Act on Climate Change and Health) (Study Identifies Messages Most Likely to Inspire Americans to Act on Climate Change and Health).)*
• Dasandi et al. (2022) – China, Germany, India, United Kingdom, United States – Conjoint experiment (survey-based) with ~7,500 adults across five countries, testing how different climate message frames affect support for climate mitigation policies (Positive, Global, and Health or Environment Framing Bolsters Public Support for Climate Policies). Each respondent saw messages randomly varying four attributes: valence (positive “opportunity” vs. negative “threat”), theme (health vs. environment vs. economy vs. migration), scale (individual/local vs. national vs. global focus), and timeframe (present impacts vs. future 2030/2050 impacts) (Positive, Global, and Health or Environment Framing Bolsters Public Support for Climate Policies). Findings: Overall, framing climate change as a health issue significantly increased public support for climate policies – this health frame had a positive effect in four of the five countries (with a slight positive-but-non-significant trend in Germany) (Positive, Global, and Health or Environment Framing Bolsters Public Support for Climate Policies). Notably, a positive (opportunity-focused) tone also boosted support across most samples (Positive, Global, and Health or Environment Framing Bolsters Public Support for Climate Policies). Across demographics, the health frame worked similarly well – its effectiveness did not differ by respondents’ age, gender, education, or income levels in the pooled analysis (Positive, Global, and Health or Environment Framing Bolsters Public Support for Climate Policies). However, a person’s prior concern about climate change mattered greatly: among individuals who were initially unconcerned, the health-focused messages were one of the few that moved the needle. In this unconcerned segment, a health frame raised policy support significantly (where an environmental frame had little effect or even decreased support in some cases) (Positive, Global, and Health or Environment Framing Bolsters Public Support for Climate Policies). This pattern was especially strong in the USA and China samples (Positive, Global, and Health or Environment Framing Bolsters Public Support for Climate Policies). In sum, this multinational evidence suggests health messaging can engage even skeptical audiences and works across cultural contexts. (Citation: “Positive, global, and health or environment framing bolsters public support for climate policies,” Communications Earth & Environment 3, art. 239 (2022) (Positive, Global, and Health or Environment Framing Bolsters Public Support for Climate Policies) (Positive, Global, and Health or Environment Framing Bolsters Public Support for Climate Policies).)*
• Chu & Yang (2020) – United States – Survey experiment with U.S. adults (quota-sampled). This study examined issue framing (comparing a public health frame vs. an economic frame for climate change) and psychological distance framing (impacts happening in a distant country vs. local U.S. impacts). It also measured participants’ political ideology and environmental values to see moderating effects. Findings: The health frame elicited stronger concern among liberals but provoked skepticism among conservatives, whereas an economic frame was somewhat more neutral. As a result, framing climate change as a health threat widened the polarization in risk perception and policy support between liberals and conservatives ( Their Economy and Our Health: Communicating Climate Change to the Divided American Public - PMC ). In statistical terms, there was a significant interaction: liberals rated climate risks much higher under a health frame, but conservatives showed lower risk perception under the health frame than under the economy frame ( Their Economy and Our Health: Communicating Climate Change to the Divided American Public - PMC ). The authors suggest that some conservatives reacted defensively to the health messaging, possibly due to motivated reasoning (rejecting messages inconsistent with their prior beliefs about climate). Additionally, framing climate impacts as psychologically distant (far away) versus local also increased the ideological divide, whereas making impacts feel local did not substantially reduce polarization ( Their Economy and Our Health: Communicating Climate Change to the Divided American Public - PMC ). This study highlights that health-focused messages can backfire with certain audiences unless crafted carefully – a one-size-fits-all health narrative may not appeal to strong climate skeptics. (Citation: “Their Economy and Our Health: Communicating Climate Change to the Divided American Public,” International Journal of Environmental Research and Public Health 17(21): VIII (2020) ( Their Economy and Our Health: Communicating Climate Change to the Divided American Public - PMC ) ( Their Economy and Our Health: Communicating Climate Change to the Divided American Public - PMC ).)*
• Maibach, van der Linden et al. (2023) – United States – Survey experiment with 2,201 U.S. adults (quota-sample representative of the U.S.). This study, published in The Lancet Planetary Health, tested the added effect of identifying opponents to climate action in health-based climate messages. All participants read a message from a health professional about the health risks of climate change (e.g. heatwaves, disease, pollution) – but in some conditions the message also named a culpable party blocking action (either “fossil fuel companies,” “politicians opposing action,” or both). Findings: Climate-health messages improved climate attitudes across the board relative to a no-message control: people who saw any health-impact message showed higher issue engagement, policy support, and intention to advocate than those who saw none (Calling attention to opponents of climate action in climate and health messaging - The Lancet Planetary Health). Importantly, including a named “opponent” significantly amplified these effects. Messages that called out opposition (especially combining corporations + politicians) led to the largest gains in support for climate mitigation policies and advocacy intentions (Calling attention to opponents of climate action in climate and health messaging - The Lancet Planetary Health) (Calling attention to opponents of climate action in climate and health messaging - The Lancet Planetary Health). This approach was effective across political affiliations, with especially strong impacts on self-identified conservatives (who responded more favorably when the message identified villains contributing to the climate/health problem) (Calling attention to opponents of climate action in climate and health messaging - The Lancet Planetary Health). Additionally, respondents who read the health-professional messages – particularly those naming opponents – reported greater trust in the messenger (the doctors/nurses) compared to the control group (Calling attention to opponents of climate action in climate and health messaging - The Lancet Planetary Health). The authors conclude that health messages which not only inform about harms but also tap into a righteous anger (by highlighting those responsible for endangering public health) can motivate broader support for action and even reduce partisan divides on climate (Calling attention to opponents of climate action in climate and health messaging - The Lancet Planetary Health). (Citation: “Calling attention to opponents of climate action in climate and health messaging,” Lancet Planetary Health 7(11): e906-e914 (2023) (Calling attention to opponents of climate action in climate and health messaging - The Lancet Planetary Health) (Calling attention to opponents of climate action in climate and health messaging - The Lancet Planetary Health).)*

Conclusions

Health-centered climate communication shows considerable promise for engaging the public. In the short term, messages about climate change’s health impacts consistently increase people’s concern and support for climate solutions, and can spur intentions to act. These effects are often strongest when messaging also offers hope through solutions and highlights social norms (showing that taking action is both beneficial and popular) (Study Identifies Messages Most Likely to Inspire Americans to Act on Climate Change and Health) (Study Identifies Messages Most Likely to Inspire Americans to Act on Climate Change and Health).

Such framing tends to work across many demographic groups. Researchers have not observed large differences by age or gender – young and old, men and women alike can find health arguments compelling (Positive, Global, and Health or Environment Framing Bolsters Public Support for Climate Policies). The most notable differences are along ideological lines: moderate and even moderately conservative audiences can be swayed by health frames (sometimes more so than environmental frames) (How Americans Respond to Information About Global Warming's Health Impacts: Evidence From a National Survey Experiment - PubMed) (Positive, Global, and Health or Environment Framing Bolsters Public Support for Climate Policies), but strongly skeptical conservatives may resist these messages if they perceive them as partisan or threatening to their worldview ( Their Economy and Our Health: Communicating Climate Change to the Divided American Public - PMC ). To reach those groups, tailoring the message is key – for instance, using trusted conservative messengers, emphasizing co-benefits, or identifying common enemies can bridge the gap and reduce polarization (Calling attention to opponents of climate action in climate and health messaging - The Lancet Planetary Health).

Overall, recent high-quality studies – including international experiments and systematic reviews – support the idea that framing climate change as a human health crisis can make the issue more personally relevant and galvanize broader engagement (Public engagement with health and climate change around the world: a Google Trends analysis - The Lancet Planetary Health) (Communication research to improve engagement with climate change and human health: A review - PubMed). As one 2023 research review summarized, “messages that convey the health harms of climate change and highlight the health benefits of climate solutions may be especially effective in building public and political will” (Communication research to improve engagement with climate change and human health: A review - PubMed). In practice, this means that public health professionals, climate communicators, and advocates have a potent tool: by clearly connecting climate action to protecting people’s health and well-being, they can inspire diverse audiences – from youth to seniors, and across the political spectrum – to support and participate in tackling climate change.

Sources:

• Kotcher, J. et al. (2018). How Americans Respond to Information About Global Warming’s Health Impacts: Evidence from a National Survey Experiment. GeoHealth, 2(9), 262–275. DOI: 10.1029/2018GH000154 (How Americans Respond to Information About Global Warming's Health Impacts: Evidence From a National Survey Experiment - PubMed) (How Americans Respond to Information About Global Warming's Health Impacts: Evidence From a National Survey Experiment - PubMed)
• Feldman, L., Kotcher, J., et al. (2021). Advocacy messages about climate and health are more effective when they include information about risks, solutions, and a normative appeal: Evidence from a conjoint experiment. J. Climate Change & Health, 3, 100030 (Study Identifies Messages Most Likely to Inspire Americans to Act on Climate Change and Health) (Study Identifies Messages Most Likely to Inspire Americans to Act on Climate Change and Health)
• Dasandi, N. et al. (2022). Positive, global, and health or environment framing bolsters public support for climate policies. Communications Earth & Environment, 3: 239 (Positive, Global, and Health or Environment Framing Bolsters Public Support for Climate Policies) (Positive, Global, and Health or Environment Framing Bolsters Public Support for Climate Policies)
• Chu, H. & Yang, J. (2020). Their Economy and Our Health: Communicating Climate Change to the Divided American Public. Int. J. Environ. Res. Public Health, 17(21): 771 ( Their Economy and Our Health: Communicating Climate Change to the Divided American Public - PMC )
• Maibach, E. et al. (2023). Calling attention to opponents of climate action in climate and health messaging. Lancet Planetary Health, 7(11): e906-e914 (Calling attention to opponents of climate action in climate and health messaging - The Lancet Planetary Health) (Calling attention to opponents of climate action in climate and health messaging - The Lancet Planetary Health)
• Campbell, E., et al. (2023). Communication research to improve engagement with climate change and human health: a review. Front. Public Health, 10: 1086858 (Communication research to improve engagement with climate change and human health: A review - PubMed) (Review of 90+ studies on climate-health communication)