Is Sitting Really the New Smoking? A Scientific Examination
The phrase “Sitting is the new smoking” has gained traction in health and fitness circles, with many claiming that prolonged sitting can be just as harmful as smoking. But is this comparison valid? In this post, we’ll explore whether sitting deserves the same infamy as smoking by examining the science behind each, with a nod to anthropologist David Lieberman’s work on human physical activity.
The Impact of Smoking on Health
Before comparing sitting to smoking, it’s essential to understand the profound health consequences of smoking, which is one of the leading causes of preventable death worldwide.
- Cigarette Consumption and Smoking Prevalence: In the United States, about 30.8 million adults still smoke cigarettes, with over 1,600 youth trying their first cigarette daily (CDC, 2023).
- Health Risks of Smoking: Smoking increases the risk of numerous diseases, including lung cancer (by over 23 times), chronic bronchitis (17 times), coronary heart disease (4 times), and a host of other conditions such as macular degeneration, diabetes, and reduced immune function (CDC, 2023). Smokers, on average, live 10 years less than non-smokers and account for nearly 480,000 deaths per year (USDHHS, 2014).
Comparative Smoking Data:
- U.S. Healthcare Costs: The U.S. spends approximately $225 billion annually on medical care related to smoking (USDHHS, 2020).
- Mortality Rates: Cigarette smoking remains responsible for approximately 1 in 5 deaths annually (CDC, 2023).
What Do Experts Say About Sitting?
Dr. James A. Levine first coined the phrase “Sitting is the new smoking” and suggested that prolonged sitting could lead to significant health risks, asserting that individuals lose up to two hours of life for every hour they spend sitting (Levine, 2014). But how does this claim hold up to scrutiny?
- Sitting Duration: According to a study from the National Health and Nutrition Examination Survey (NHANES), the average American adult spends approximately 6.4 hours a day sitting, contributing to various health risks, although not nearly as severe as those associated with smoking (Matthews et al., 2008).
- Life Expectancy Impact: If we assume an individual sits for eight hours daily over an average lifespan of 78.8 years, they would spend approximately 26 years sitting. However, studies suggest that the loss of life from sitting is more nuanced than Levine’s assertion (Matthews et al., 2012).
What Happens When We Sit?
Sitting itself is not inherently dangerous. However, the problem arises from prolonged periods of passive sitting, often in poor postures, which can lead to a range of musculoskeletal and metabolic issues.
- Metabolic Effects of Sitting: Prolonged sitting has been associated with increased adiposity (body fat), especially in women, and contributes to cardiometabolic risk factors like elevated triglycerides and reduced HDL cholesterol (Barlow et al., 2016). However, in men, the primary risk factor related to sitting is obesity.
- Postural Changes: Sitting for long periods, particularly in chairs, can lead to muscle imbalances such as upper crossed syndrome, characterized by rounded shoulders and weak core muscles (Kendall et al., 2019). Over time, this posture may lead to issues such as thoracic outlet syndrome, tension headaches, and lumbar spine degeneration.
Did Our Ancestors Sit Like Us?
In his book Exercised, paleoanthropologist David Lieberman points out that while humans have always rested, our modern sedentary lifestyle is far removed from the activity patterns of our ancestors. Lieberman describes how hunter-gatherers, such as the Hadza people of Tanzania, engage in long periods of resting, but they typically squat rather than sit on chairs (Lieberman, 2021).
- Squatting vs. Sitting: Squatting requires engagement of core and leg muscles, improving joint mobility and posture. By contrast, modern sitting in chairs can weaken muscles and reduce range of motion in the lower body (Lieberman, 2021).
- Hunter-Gatherer Activity Levels: While hunter-gatherers spend about the same amount of time resting as modern sedentary people, their overall daily physical activity is far greater, with moderate-to-vigorous physical activity making up several hours of their day (Pontzer et al., 2012).
Comparison: Smokers vs. Sitters vs. Hunter-Gatherers
| Metric | Smokers | Sitters (U.S. adults) | Modern Hunter-Gatherers (e.g., Hadza) |
| Health Impact | High risk of cancer, heart disease, lung disease | Risk of metabolic syndrome, obesity, musculoskeletal issues | Lower rates of chronic disease despite similar sitting time |
| Life Expectancy | 10 years shorter on average | Some evidence of reduced life expectancy with prolonged sitting | Comparable life expectancy to U.S. adults despite high activity levels |
| Physical Activity | Typically low | Often low, though varies by individual | High levels of moderate-to-vigorous physical activity |
| Posture | Not relevant | Associated with poor posture and muscle imbalances | Active postures (e.g., squatting) maintain muscle strength and mobility |
Conclusion: Is Sitting the New Smoking?
In conclusion, while sitting for long periods can negatively impact health, particularly when associated with poor posture and low physical activity, it is not as dangerous as smoking. Smoking remains the leading cause of preventable death and disease, while sitting can be mitigated by incorporating more activity into daily life, improving posture, and engaging in active sitting strategies.
Instead of viewing sitting as the “new smoking,” it’s more productive to recognize that humans have always needed rest, but in modern times, we rest in ways that can weaken us. By adopting more active resting postures—such as squatting or using standing desks—and increasing overall physical activity, we can address the negative effects of prolonged sitting without drastic lifestyle changes.
For more practical tips on incorporating active postures into your daily routine, check out our article on the “Hunter-Gatherer Office.”
Sources:
- Barlow, C. E., LaMonte, M. J., FitzGerald, S. J., Radford, N. B., & Levine, B. D. (2016). Cardiorespiratory fitness is an independent predictor of hypertension incidence among initially normotensive healthy women. American Journal of Epidemiology, 183(10), 908-914.
- Centers for Disease Control and Prevention (CDC). (2023). Fast facts on smoking and tobacco use. Retrieved from https://www.cdc.gov
- Kendall, F. P., McCreary, E. K., & Provance, P. G. (2019). Muscles: Testing and Function with Posture and Pain. 5th ed. Lippincott Williams & Wilkins.
- Lieberman, D. E. (2021). Exercised: Why Something We Never Evolved to Do Is Healthy and Rewarding. Pantheon.
- Matthews, C. E., Chen, K. Y., Freedson, P. S., Buchowski, M. S., Beech, B. M., Pate, R. R., & Troiano, R. P. (2008). Amount of time spent in sedentary behaviors in the United States, 2003-2004. American Journal of Epidemiology, 167(7), 875-881.
- Pontzer, H., Raichlen, D. A., Gordon, A. D., Schroepfer-Walker, K., & O’Neill, M. C. (2012). Hunter-gatherer energetics and human obesity. PLoS ONE, 7(7), e40503.
- U.S. Department of Health and Human Services (USDHHS). (2014). The Health Consequences of Smoking—50 Years of Progress: A Report of the Surgeon General.