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Taxes, Health-Warning Labels May Help Limit Consumption of Sugary Beverages and Improve Health

To combat obesity and diabetes, lawmakers in a number of U.S. cities have taxed sodas, sports drinks, and sweetened tea, and many are now considering health warning labels.

Growing evidence suggests that both strategies—taxes and warning labels—can reduce the purchase and consumption of sugary drinks, research supported by the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) shows.

Health-Warning Labels Influence What People Buy and Consume

Even brief exposure to health warnings on sugar-sweetened beverages reduces purchases of those beverages, providing evidence that such warnings can promote healthier drink choices, a new study demonstrates.1

A team of researchers from the University of North Carolina at Chapel Hill (UNC)—including Anna Grummon, Lindsey Smith Taillie, Shelley Golden, Marissa Hall, and Noel Brewer—examined how health warnings influence what consumers actually buy in real settings. This randomized controlled trial assigned 400 consumers of sugary beverages to groups that saw either a health warning or a label that looked like a barcode.

“We worked in a convenience-store laboratory that allowed us to control whether the sugary drinks had warnings,” explains Grummon, now at Harvard University. “We are also one of the first studies to measure what consumers actually buy after seeing warnings, when they have their own money on the line.”

Participants who saw the health warning labels purchased about 22% fewer calories from sugary drinks compared with participants who saw a neutral label. The study also found that the warnings were influential across diverse groups: The effect of health warnings on beverage purchases did not differ by participants’ race/ethnicity, education, age, gender, sexual orientation, income, body weight, or health-literacy level.

According to Grummon, critics of health warning labels argue that consumers won’t notice or pay attention to the warnings. However, three-quarters of the participants in this study reported noticing the health warnings, and most of those participants also reported that they read and looked closely at the labels.

In another study, Grummon and Hall synthesized the findings of 23 studies and found that health warnings labels not only reduced purchases of sugary drinks but also caused stronger emotional responses, increased perceptions that sugary drinks contribute to disease, and reduced intentions to purchase or consume sugary drinks.2 All these responses are key indicators when it comes to long-term behavior change, they note.

“Our findings suggest that sugary drink warnings help consumers better understand products’ healthfulness and encourage them to make healthier choices about what drinks to buy,” says Grummon.

In a related mathematical simulation, UNC researchers show that a national policy requiring health labels on sugar-sweetened beverages could reduce obesity prevalence by about 3.1 percentage points over five years, if sustained.3

“While three percentage points might sound modest, on a national scale it equates to more than five million fewer people with obesity,” says Grummon. “Warnings are a highly scalable strategy for helping consumers make healthier choices. These findings suggest that warnings are also promising for addressing obesity in the U.S.”

Improved Child Health Projected in Wake of Mexico’s Soda Tax

The Mexican government enacted the first national tax on sugar-sweetened beverages after a 2012 study indicated that more than 70% of the country’s population was overweight or obese, and that in excess of 70% of the added sugar calories in the Mexican diet were coming from sugary drinks.

In the two-year period spanning 2014 to 2015, a research team that included Barry M. Popkin and Shu Wen Ng of UNC found that:

  • The one-peso-per-liter excise tax on sugar-sweetened beverages in Mexico resulted in a 6% reduction in purchases of taxed beverages during the first year and continued to decline, with a 10% decrease in purchases in the second year.
  • During the same study period, purchases of untaxed beverages such as bottled water increased 2.1%.
  • Residents of households with lower socioeconomic levels, for whom health care costs are most burdensome, reduced their purchases of sweetened beverages the most.4

The findings run counter to initial reports from the sugar-sweetened soda industry, which said that the purchases of sugary drinks actually went up after the initial tax year. However, the researchers found those reports did not account for numerous significant factors, including inflation and shifts in population.

In addition, a new analysis co-authored by Popkin estimates that Mexico’s sugar-sweetened beverage tax could result in meaningful weight control and life-long health benefits for the country’s children and adolescents, particularly those who had been high consumers of the beverages before the tax.5 Childhood obesity is a strong predictor for obesity later in life, which can also lead to chronic illnesses such as diabetes, hypertension, and heart disease, the researchers emphasize.

To estimate the one-year effect of the tax on the body weight of children ages 5 to 17, by taking into account patterns of childhood growth and obesity in Mexico and assuming that the known reductions in sugar-sweetened beverage purchases would reflect changes in consumption.

Findings show that one year after the implementation of the current tax, children and adolescents should experience an average reduction in body weight of 0.26 and 0.61 kg (one kilogram equals about 2.2 pounds). For those who had been high consumers of sugary drinks, the team estimates the positive impact on body weight would be even greater, with an average body weight reduction of 0.50 kg for children and 0.87 kg for adolescents. Sustained over several years, such weight loss could mean some children and adolescents would not longer be considered obsese.

“Taxation represents one of the most effective ways to reduce consumption of unhealthy sugar-sweetened beverages, which can make a meaningful impact on future excessive weight gain and significantly reduce the long-term risks of becoming obese,” says Popkin. “If the taxation revenue is used to support child and adolescent healthy eating, then the benefits of such taxes are enhanced.”

Public Support Is Key to Policies Limiting Sugary Beverages

For taxes on sugary beverages to become a widely used strategy for improving public health, public support and acceptance are key.

Public opinion on the policies’ unintended consequences may affect attitudes toward the policy, argue Melissa Knox, Jessica Jones-Smith, and Vanessa Oddo of the University of Washington, who analyzed perceptions of the effects of Seattle’s 2017 sugary beverage tax.6

“We find that a majority of participants (59%) support the sugary beverage tax in Seattle and correspondingly, most people believed that the tax will positively impact health, and will not negatively affect general and personal economics in Seattle,” they report. “However, lower-income, versus higher-income, respondents were more concerned about the possible negative economic consequences of the tax,” such as job loss or increased financial costs for their family and friends.

A related study shows that attitudes toward sugary beverage taxes may be difficult to accurately estimate in phone surveys.7 Phone respondents (but not web respondents) under-report their sugary beverage consumption by about 25% and over-report positive attitudes toward the tax by about 11%, the researchers determined. These differing results likely reflect respondents’ answering interviewers’ questions in ways they believe are more socially desirable or acceptable rather than choosing responses that reflect their true thoughts or feelings, a tendency known as social desirability bias.

The researchers offer advice to lawmakers implementing soda taxes.

  • Policymakers “should be wary of solely relying on self-reported measures of intake when evaluating the effectiveness of these policies,” they write, noting that consumers may consume more sweetened beverages than they report.
  • Lawmakers should strengthen “their public messaging regarding the health and economic benefits of sweetened beverage taxes, even if they believe that attitudes are generally positive. Without a pro-tax messaging campaign that informs the public about the positive health and economic effects of these taxes, the taxes may eventually lose public support.”

The researchers point out that “recent successful efforts to block U.S. municipalities from enacting future beverage taxes by banning the taxes at the state level have relied heavily on informational campaigns that focused on the negative economic effects of the taxes. These campaigns, often funded by the beverage industry, may ultimately shift social norms in the direction of more favorable attitudes toward sweetened beverages, with unpredictable effects on public health.”

This article was produced under a grant from the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD). The Communications and Marketing team at the Gillings School of Global Public Health at the University of North Carolina at Chapel Hill contributed to this article. The work of researchers from the following NICHD-funded Population Dynamics Research Centers was highlighted: University of North Carolina at Chapel Hill (P2CHD050924) and University of Washington (5P2CHD042828-18).



  1. Anna H. Grummon et al., “Sugar-Sweetened Beverage Health Warnings and Purchases: A Randomized Controlled Trial,” American Journal of Preventive Medicine 57, no. 5 (2019): 601-10.
  2. Anna H. Grummon and Marissa G. Hall, “Sugary Drink Warnings: A Meta-Analysis of Experimental Studies,” PLOS Medicine (2020), https://doi.org/10.1371/journal.pmed.1003120.
  3. Anna H. Grummon et al., “Health Warnings on Sugar-Sweetened Beverages: Simulation of Impacts on Diet and Obesity Among U.S. Adults,” American Journal of Preventive Medicine 57, no. 6 (2019): 765-74.
  4. M. Arantxa-Colchero et al., “In Mexico, Evidence of Sustained Consumer Response Two Years After Implementing a Sugar-Sweetened Beverage Tax,” Health Affairs 36, no. 3 (2017): https://doi.org/10.1377/hlthaff.2016.1231
  5. Rossana Torres-Álvarez et al., “Body Weight Impact of the Sugar-Sweetened Beverages Tax in Mexican Children: A Modeling Study,” Pediatric Obesity 15, no. 8 (2020): e12636, https://doi.org/10.1111/ijpo.12636.
  6. Vanessa M. Oddo et al., “Perceptions of the Possible Health and Economic Impacts of Seattle’s Sugary Beverage Tax,” BMC Public Health 19 (2019): 910.
  7. Melissa A. Knox et al., “Is the Public Sweet on Sugary Beverages? Social Desirability Bias and Sweetened Beverage Taxes,” Economics & Human Biology 38 (2020): 100886.

Coronavirus Stress and Fear Could Take a Toll on Our Health

Stress and fear during coronavirus social isolation can alter gene activity in ways that affect your immune system, but doing good deeds can bolster health.

Heightened fears and the stress of social distancing and isolation may negatively impact the health of millions of Americans who are already feeling burdened by the effects of the novel coronavirus pandemic.

And some health experts believe that such impacts might even leave certain people more susceptible to infection by the coronavirus.

Research in the emerging field of social genomics has found that chronic social isolation and loneliness can alter gene activity in ways that inhibit an individual’s antiviral response while increasing their risk of diseases such as arteriosclerosis, cancer, and dementia over the long term.1But there’s no data yet on the effects of short-term isolation related to social distancing and stay-at-home orders.

“A lot depends on the timing and the psychology,” says Steve Cole, professor of medicine and biobehavioral sciences at the University of California, Los Angeles (UCLA).

His research, supported by the National Institute on Aging (NIA), examines how psychological experiences—including prolonged social isolation, a lifetime of poverty, and constant fear for one’s safety—can influence our immune systems and, in turn, our health.

Cole has examined the immune-response genes of socially isolated and chronically lonely people, exploring why they got sick and died faster when they contracted HIV, the virus that causes AIDS. He and his colleagues found that the fight-or-flight stress response is highly activated among chronically lonely people, triggering the expression of genes involved in inflammation while suppressing the activity of genes governing the virus-fighting Type I interferon system.2 This inflammatory response to loneliness may have evolved in early humans, enabling those separated from their tribe or social group to heal from injuries sustained without group protection, he explains.

But the fight-or-flight stress response is “a double-edge sword,” says Cole, noting that while it can help steer our immune system “toward inflammatory responses that kill bacteria,” inflammation also “fuels the growth of some other slow-brewing illnesses such as cardiovascular diseases, neurodegenerative diseases, and many types of cancer.”

Stress and Fear Can Dampen Antiviral Responses

Sustained fear and insecurity also trigger that fight-or-flight stress response, according to Cole. “The body doesn’t care what we’re afraid of—fear of the virus or fear of rejection by others, as is common in lonely people. Either type of fear will still stimulate our inflammation system, suppress our interferon system, and mess with a wide range of other physiologic systems we need to keep us healthy.”

While it is too early for studies related to the current pandemic, Cole offers what we do know about other types of coronaviruses. “Fight-or-flight stress physiology strongly suppresses the Type I interferon system, which is the body’s first line of defense against viral infections of all types. Coronaviruses are highly vulnerable to our Type I interferon responses, and it stands to reason that any stress-induced suppression of that system would leave us more vulnerable to this type of virus.”

It would be particularly tragic, he notes, if the stress of social distancing makes us more vulnerable to infection if we are exposed, even as it reduces our likelihood of exposure in the first place.

Short-Term Loneliness Is Unlikely to Make a Lasting Difference to Health

The good news is that a few weeks or months of being home alone is unlikely to noticeably affect a person’s health over the long term. The inflammation that hardens arteries and contributes to a heart attack takes many decades to build up, for example.

“The loneliness people feel after a move to a new town or the end of a romantic relationship is generally transient,” Cole says. “Any short-term change in our physiology would probably not significantly impact the long-term development of chronic illnesses like heart disease or cancer.”

Loneliness makes us focus on ourselves but redirecting that focus outward… can change our outlook, our brains, and our body chemistry.

Steve Cole, Professor of medicine and biobehavioral sciences at the University of California, Los Angeles

Doing Good For Others Can Help Us Stay Healthy

Cole and his colleagues have identified a surprising way to dampen stress-related inflammation and bolster the body’s virus-fighting capacity in chronically lonely people—altruism and purpose.3

“Loneliness makes us focus on ourselves,” he explains. “But redirecting that focus outward, toward helping others or some other self-transcendent purpose, can change our outlook, our brains, and our body chemistry.”

Older volunteers mentoring elementary school students experienced such immune system benefits. That’s according to a study led by Teresa Seeman, UCLA epidemiology professor and co-director of the UCLA and University of Southern California Center on Biodemography and Population Health.4 Those who reported the greatest increases in their sense of life purpose and meaning during the study also showed the greatest reduction in inflammation and increase in antiviral response.

During the current pandemic, focusing attention on how our own social distancing is protecting the common good and checking in on others by telephone or video conference could “very likely” counter some of the negative effects of stress and fear, says Cole.

And mounting evidence suggests that a variety of strategies—including mindfulness practices, yoga, tai chi, cognitive-behavioral stress management techniques (such as anxiety reduction, thought substitution, and coping skills), and certain drugs—can also alter the fight-or-flight signaling that increases inflammation and dampens antiviral responses, according to Cole.5

Prolonged Economic Insecurity, Poverty, and Grief Can Affect Health

What concerns Cole most right now is the potential for deepening poverty and widespread economic insecurity—particularly if unemployment persists and an economic recession takes hold. The long-term stress of living in poverty “gets under the skin,” “weathers” people, and sets them up for a host of chronic diseases at older ages, he and his colleagues find based on nationally representative Health and Retirement Study data.6

Bereavement—such as the unexpected loss of a loved one due to COVID-19, the disease caused by the novel coronavirus—is also known to worsen heart problems and raise mortality risks.7

Research on the health effects of the 2008 recession may provide clues on what to expect during the economic downturn that many are predicting in the wake of the current pandemic.  Seeman and colleagues documented a higher-than-expected rise in risk factors for heart disease and diabetes among Americans ages 45 and older following the global financial decline.8

The negative changes were most pronounced among those most likely to be affected by the economic downturn, including working-age adults and homeowners ages 65 and older “whose declining home wealth may have reduced their financial security, with less scope for recouping losses during their lifetime.” Least affected were older adults without a college degree; their reliance on Medicare and Social Security may have protected them, the researchers suggest.

Consider Spending More Time on Creative Activities

Older Americans may feel the effects of stay-at-home orders more acutely than other groups; 42% of those ages 65 and older lived alone in 2018, the largest share of any other U.S. age group.9

Those isolating themselves at home may be better off limiting television viewing and spending more time on mentally stimulating activities such as reading, carpentry, gardening, and crafting. That’s the advice of a University of Michigan researcher who studies older adults and the connections among their health, satisfaction with life, loneliness, and time use with NIA funding.10

“Spending the whole day alone listening to a constant stream of bad news is clearly not good for anyone,” says Jacqui Smith, a professor affiliated with the Michigan Center for the Demography of Aging and Institute of Social Research.

Television is passive, Smith points out. Activities that involve more social, mental, and physical engagement contribute the most to the positive side of adults’ daily emotional balance sheets, her work shows.11

This line of research, known to academics as subjective well-being, looks beyond traditional measures of physical and cognitive health to examine how older people evaluate and experience their daily lives. Researchers are finding that people who report that their lives are full of meaning and purpose tend be physically healthier and live longer than people who do not, as are those who report their day-to-day experience as largely positive and satisfying.12

For older adults confined at home by social distancing, Smith’s research underscores the positive health effects of phone conversations with friends and family, and exercise such as walks or stretching at home—activities that could benefit us all during the coronavirus pandemic, at any age.

Stay informed, Smith says, but spend more time on activities that “absorb your attention so fully that you lose track of time,” such as crafts, baking, or reading.


1Morgan Levine et al., “Contemporaneous Social Environment and the Architecture of Late-Life Gene Expression Profiles,” American Journal of Epidemiology 186, no. 5 (2017): 503-9; and Steven W. Cole, “Social Regulation of Human Gene Expression: Mechanisms and Implications for Public Health,” American Journal of Public Health 103, Supplement 1 (2013): S84-92.

2Steven W. Cole et al., “Accelerated Course of Human Immunodeficiency Virus Infection in Gay Men Who Conceal Their Homosexual Identity,” Psychosomatic Medicine 58, no. 3 (1996): 219-31; and Steven W. Cole, “Social Regulation of Human Gene Expression: Mechanisms and Implications for Public Health.” Type 1 interferons are a group of proteins that protect cells from infection by interfering with viral replication.

3Steven W. Cole, et al. “Loneliness, Eudaimonia, and the Human Conserved Transcriptional Response to Adversity,” Psychoneuroendocrinology 62, no. 1 (2015): 11-7.

4Teresa Seeman et al., “Intergenerational Mentoring, Eudaimonic Well-Being and Gene Regulation in Older Adults: A Pilot Study,” Psychoneuroendocrinology 111, no. 1 (2020): 104468.

5Jennifer M. Knight et al., “Propranolol Inhibits Molecular Risk Markers in HCT Recipients: A Phase 2 Randomized Controlled Biomarker Trial,” Blood Advances 4, no. 3 (2020): 467-76; Michael R. Irwin et al., “Cognitive Behavioral Therapy and Tai Chi Reverse Cellular and Genomic Markers of Inflammation in Late-Life Insomnia: A Randomized Controlled Trial,” Biological Psychiatry 78, no. 10 (2015): 721-9; J. David Creswell et al., “Mindfulness-Based Stress Reduction Training Reduces Loneliness and Pro-Inflammatory Gene Expression in Older Adults: A Small Randomized Controlled Trial,” Brain, Behavior, and Immunity 26, no. 7 (2012): 1095-101; Julienne E. Bower et al., “Yoga Reduces Inflammatory Signaling in Fatigued Breast Cancer Survivors: A Randomized Controlled Trial,” Psychoneuroendocrinology 43, no. 1 (2014): 20-9; and Julienne E. Bower et al., “Mindfulness Meditation for Younger Breast Cancer Survivors: A Randomized Controlled Trial,” Cancer 121, no. 8 (2015): 1231-40.

6Morgan Levine et al., “Contemporaneous Social Environment and the Architecture of Late-Life Gene Expression Profiles,” American Journal of Epidemiology 186, no. 5 (2017): 503-9.

7See multiple citations in Ashton M. Verdery and Emily Smith-Greenway, “COVID-19 and Family Bereavement in the United States,” Applied Demography, Special Issue on Covid-19, Committee on Applied Demography, Population Association of America, March 2020, pp. 1-2, www.populationassociation.org/wp-content/uploads/CAD_SpecialEdition_COVID19_March2020.pdf.

18Teresa Seeman et al., “The Great Recession Worsened Blood Pressure and Blood Glucose Levels in American Adults,” Proceedings of the National Academy of Sciences 115, no. 13 (2018): 3296-301.

9U.S. Census Bureau, 2018 American Community Survey.

10Jacqui Smith et al., “Snapshots of Mixtures of Affective Experiences in a Day: Findings From the Health and Retirement Study,” Population Ageing 7, no. 1 (2014): 55-79; and Tara L. Queen et al., “Loneliness in a Day: Activity Engagement, Time Alone, and Experienced Emotions,” Psychology and Aging 29, no. 2 (2014): 297-305.

11Smith et al., “Snapshots of Mixtures of Affective Experiences in a Day.”

12Yoichi Chida and Andrew Steptoe, “Positive Psychological Well-Being and Mortality: A Quantitative Review of Prospective Observational Studies,” Psychosomatic Medicine 70, no. 7 (2008): 741-56; and Angus Deaton and Arthur Stone, “Evaluative and Hedonic Wellbeing Among Those With and Without Children at Home,” Proceedings of the National Academy of Sciences 111, no. 4 (2014): 1328-33.