Longevity Conferences 2023
January 19, 2023
Curated list of Longevity Conferences, where you can explore the latest research and developments in the field of aging and longevity.
All Articles
The impact of hot and cold on longevity - lifestyle only for the experts?
Temperature tweaking can prevent cardiovascular diseases, infections, or neurodegeneration diseases.
.jpg)
Highlights
- Staying in cold climate does not prolong longevity of homeotherms
- Calorie restriction lowers body temperature and leads to longer life
- Regular sauna bathing improves health and as a moderate heat shock could also induce hormetic response
Introduction
Temperature is a fundamental feature of every ecosystem and organism. On Earth, the highest temperature ever measured was 56.7 °C (134.1 °F) at Furnace Creek Ranch, in Death Valley in the United States and the coldest was - 126 °F (- 88 °C) at Vostok Station in Antarctica, while the average temperature is 59 °F (15 °C). Some organisms can grow and reproduce at temperatures as low as - 15 °C, such as snow algae Chlamydomonas nivalis, and as high as 122 °C in the case of thermophilic archaea. The situation is different for the human body, which is not thriving in extreme temperatures.
Staying in a cold environment is not enough
The average normal body temperature is 98.6 °F (37°C), but it can naturally slightly vary from 97 °F (36.1 °C) to 99 °F (37.2 °C). Body temperature is one of the key vital signs, and even minor variations have an immense impact. Any temperature above 100.4 °F (38 °C) might relate to infection or illness. Exposing our bodies to extreme temperatures can also relatively quickly lead to negative states such as hypothermia or overheating (1, 2). It also leads to the effect of hormesis which is the response of the organism to a mild stressor resulting in improved health and longevity (3). So, if the environment and body temperature are so crucial for health and well-being, does it actually impact longevity, and should it be suggested as a preventive lifestyle change?
Research on poikilotherms – organisms that can not regulate their own body temperature, such as various species of fish, amphibians, and reptiles, have proven that they could live longer in colder temperatures. For example, a Brazilian fish Austrolebias adloffi – grows and ages slower and lives longer when living in water with temperature lowered by 3-5 °C that lowered its core body temperature (4, 5). The same was not proven for homeotherms, which are organisms able to modulate their body temperature, such as humans. Research on rodents shows either negative or neutral influence of growing in the colder temperatures (6). It is due to the thermoregulation abilities of the homeotherms – while living in colder climates, they can adapt by reduced heat dispersion, heat production, and increased energy expenditure (5, 7). So, our body temperature would not change the same way as in poikilotherms.
Nevertheless, a lower core body temperature was proven to prolong life thanks to studies on the transgenic mice with higher hypothalamic temperatures leading to their core body temperature constant reduction by 0.5-0.6 °C (8). To obtain a similar result without genetic manipulation there is a simple method that can be used which is a calorie restriction diet such as the popular intermittent fasting regime (9). The impact of the core body temperature lowering calorie restriction diet on longevity was tested on mice and preliminary on humans. (10, 11). In humans, it was proven that indeed calorie restriction can lower body temperature (10), and in mice models, data reveals that constantly lower core body temperature correlates with prolonged lifespan (12). To sum up, a controlled, balanced calorie restriction diet was suggested to be the most effective and simple way to prolong lifespan and slow down aging by reducing body temperature.
Benefits and risks of cold water swimming
Researchers suggest that chronic cold exposure could be potentially harmful, whereas intermittent cold exposure results in health benefits but do not extend lifespan (13). But what about short shock-like exposures to cold? Cold water swimming, as an example, is a tradition in northern countries, and it was thoroughly researched in connection to health benefits. Numerous field studies come from Scandinavia and Eastern Europe on various topics related to cold water swimming, such as adaptation to the cold, changes in lipid metabolism, effects on the immune system, and hormonal balance. Recreational winter swimming is performed mostly in water temperatures between 10°C and 16°C for short periods and is becoming increasingly popular. This whole-body stressful condition done correctly and regularly can lead to adaptation to cold or even increased tolerance for stressors and body hardening (14). Studies have suggested that it has various health benefits such as fewer upper respiratory tract infections thanks to improved immune response, blood pressure lowering, increase of insulin sensitivity, and overall antidepressant effect, boosting the well-being. Nevertheless, cold water swimming is also a risky hobby because the rapid body warmth loss can lead to hypothermia, cardiac arrhythmia, hemostasis, unconsciousness, and even cardiac arrest and death. It is critical for winter swimming to be performed gradually and with proper preparation and acclimatization. It is suggested to start acclimatization by regular swimming in the summer months and continue through colder months in fall and into winter while avoiding extreme cold conditions for at least the first season of cold swimming. Each swimming session should be preceded and ended by some form of exercise activity such as jogging to maintain and restore the body temperature. To avoid injury or death, it should always be performed under supervision (15).
Sauna bathing
Extremely warm or cold temperature is considered a challenge and a stressor to human health and body homeostasis. Recent studies have proven that heat stress might be highly beneficial for human health (16). Finnish Kuopio Ischemic Heart Disease Risk Factor Study was held on a randomly selected sample of 3433 men aged 42 to 60 years who resided in Kuopio, Finland, and regularly having Finish sauna bathing sessions. The study reported that subjects who were sauna bathing more frequently had a reduced risk of sudden cardiac death, fatal coronary heart disease, fatal cardiovascular disease, and all-cause mortality (17). The same cohort was also checked for the prevalence of dementia and Alzheimer’s disease. The results concluded a strong inverse association between regular sauna bathing and the lower risk of dementia and Alzheimer’s disease. Moreover, sauna bathing, an activity that promotes relaxation and well-being, may be an intervention recommendable to prevent or slow down the development of memory diseases in healthy adults (18). There is also a proven beneficial impact of regular sauna bathing for the risk of respiratory infections, pneumonia, stroke, or venous thromboembolism. There is evidence that the lower risk of chronic and acute diseases due to frequent sauna bathing might be connected to the reduction in inflammation (19-23). Moderate heat shock could also induce hormetic response by means of promoting the activity of heat shock proteins (HSPs), which may extend lifespan (3). Taken together, the pleasure of frequent sauna bathing can prolong our life due to preventing many age-related diseases as well.
Temperature changes can prolong your life
Changing the core body temperature either by an internal way such as a calorie restriction diet or externally by extreme cold and hot exposure can benefit our health and longevity. Once implemented into the lifestyle, temperature tweaking can prevent cardiovascular diseases, infections, or neurodegeneration diseases. At the same time, it is a condition considered stressful to the body. It has to be applied correctly to avoid risks such as malnutrition during calorie restriction diet, hypothermia during cold water swimming, and overheating during sauna bathing. Planning to pursue any of these activities regularly should be first always consulted with a physician and in case of cold water swimming, the cardiologist as well. All the metabolic changes happening in the human body during core temperature alterations are not well understood yet and still need numerous studies to accept them as fully safe and healthy.
References
1. McKay CP. Requirements and limits for life in the context of exoplanets. Proc Natl Acad Sci U S A. 2014;111(35):12628-33.
2. Geneva, II, Cuzzo B, Fazili T, Javaid W. Normal Body Temperature: A Systematic Review. Open Forum Infect Dis. 2019;6(4):ofz032.
3. Lagisz M, Hector KL, Nakagawa S. Life extension after heat shock exposure: assessing meta-analytic evidence for hormesis. Ageing Res Rev. 2013;12(2):653-60.
4. Liu RK, Walford RL. Increased Growth and Life-span with Lowered Ambient Temperature in the Annual Fish, Cynolebias adloffi. Nature. 1966;212(5067):1277-8.
5. Conti B. Considerations on temperature, longevity and aging. Cell Mol Life Sci. 2008;65(11):1626-30.
6. Vaanholt LM, Daan S, Schubert KA, Visser GH. Metabolism and aging: effects of cold exposure on metabolic rate, body composition, and longevity in mice. Physiol Biochem Zool. 2009;82(4):314-24.
7. Ocobock C. Human energy expenditure, allocation, and interactions in natural temperate, hot, and cold environments. Am J Phys Anthropol. 2016;161(4):667-75.
8. Conti B, Sanchez-Alavez M, Winsky-Sommerer R, Morale MC, Lucero J, Brownell S, et al. Transgenic mice with a reduced core body temperature have an increased life span. Science. 2006;314(5800):825-8.
9. McCay CM, Crowell MF, Maynard LA. The Effect of Retarded Growth Upon the Length of Life Span and Upon the Ultimate Body Size: One Figure. The Journal of Nutrition. 1935;10(1):63-79.
10. Redman LM, Martin CK, Williamson DA, Ravussin E. Effect of caloric restriction in non-obese humans on physiological, psychological and behavioral outcomes. Physiol Behav. 2008;94(5):643-8.
11. Carrillo AE, Flouris AD. Caloric restriction and longevity: effects of reduced body temperature. Ageing Res Rev. 2011;10(1):153-62.
12. Keil G, Cummings E, de Magalhaes JP. Being cool: how body temperature influences ageing and longevity. Biogerontology. 2015;16(4):383-97.
13. Holloszy JO, Smith EK. Longevity of cold-exposed rats: a reevaluation of the "rate-of-living theory". J Appl Physiol (1985). 1986;61(5):1656-60.
14. Manolis AS, Manolis SA, Manolis AA, Manolis TA, Apostolaki N, Melita H. Winter Swimming: Body Hardening and Cardiorespiratory Protection Via Sustainable Acclimation. Curr Sports Med Rep. 2019;18(11):401-15.
15. Knechtle B, Waskiewicz Z, Sousa CV, Hill L, Nikolaidis PT. Cold Water Swimming-Benefits and Risks: A Narrative Review. Int J Environ Res Public Health. 2020;17(23).
16. Heinonen I, Laukkanen JA. Effects of heat and cold on health, with special reference to Finnish sauna bathing. Am J Physiol Regul Integr Comp Physiol. 2018;314(5):R629-R38.
17. Laukkanen T, Khan H, Zaccardi F, Laukkanen JA. Association between sauna bathing and fatal cardiovascular and all-cause mortality events. JAMA Intern Med. 2015;175(4):542-8.
18. Laukkanen T, Kunutsor S, Kauhanen J, Laukkanen JA. Sauna bathing is inversely associated with dementia and Alzheimer's disease in middle-aged Finnish men. Age Ageing. 2017;46(2):245-9.
19. Kunutsor SK, Khan H, Zaccardi F, Laukkanen T, Willeit P, Laukkanen JA. Sauna bathing reduces the risk of stroke in Finnish men and women: A prospective cohort study. Neurology. 2018;90(22):e1937-e44.
20. Kunutsor SK, Laukkanen T, Laukkanen JA. Frequent sauna bathing may reduce the risk of pneumonia in middle-aged Caucasian men: The KIHD prospective cohort study. Respir Med. 2017;132:161-3.
21. Kunutsor SK, Laukkanen T, Laukkanen JA. Sauna bathing reduces the risk of respiratory diseases: a long-term prospective cohort study. Eur J Epidemiol. 2017;32(12):1107-11.
22. Kunutsor SK, Laukkanen T, Laukkanen JA. Longitudinal associations of sauna bathing with inflammation and oxidative stress: the KIHD prospective cohort study. Ann Med. 2018;50(5):437-42.
23. Kunutsor SK, Makikallio TH, Khan H, Laukkanen T, Kauhanen J, Laukkanen JA. Sauna bathing reduces the risk of venous thromboembolism: a prospective cohort study. Eur J Epidemiol. 2019;34(10):983-6.
Read this article now
Sign up to get immediate access to this article and professional education in longevity medicine.
Oops! Something went wrong while submitting the form.
OUR partnering associations
Highlights
- Staying in cold climate does not prolong longevity of homeotherms
- Calorie restriction lowers body temperature and leads to longer life
- Regular sauna bathing improves health and as a moderate heat shock could also induce hormetic response
Introduction
Temperature is a fundamental feature of every ecosystem and organism. On Earth, the highest temperature ever measured was 56.7 °C (134.1 °F) at Furnace Creek Ranch, in Death Valley in the United States and the coldest was - 126 °F (- 88 °C) at Vostok Station in Antarctica, while the average temperature is 59 °F (15 °C). Some organisms can grow and reproduce at temperatures as low as - 15 °C, such as snow algae Chlamydomonas nivalis, and as high as 122 °C in the case of thermophilic archaea. The situation is different for the human body, which is not thriving in extreme temperatures.
Staying in a cold environment is not enough
The average normal body temperature is 98.6 °F (37°C), but it can naturally slightly vary from 97 °F (36.1 °C) to 99 °F (37.2 °C). Body temperature is one of the key vital signs, and even minor variations have an immense impact. Any temperature above 100.4 °F (38 °C) might relate to infection or illness. Exposing our bodies to extreme temperatures can also relatively quickly lead to negative states such as hypothermia or overheating (1, 2). It also leads to the effect of hormesis which is the response of the organism to a mild stressor resulting in improved health and longevity (3). So, if the environment and body temperature are so crucial for health and well-being, does it actually impact longevity, and should it be suggested as a preventive lifestyle change?
Research on poikilotherms – organisms that can not regulate their own body temperature, such as various species of fish, amphibians, and reptiles, have proven that they could live longer in colder temperatures. For example, a Brazilian fish Austrolebias adloffi – grows and ages slower and lives longer when living in water with temperature lowered by 3-5 °C that lowered its core body temperature (4, 5). The same was not proven for homeotherms, which are organisms able to modulate their body temperature, such as humans. Research on rodents shows either negative or neutral influence of growing in the colder temperatures (6). It is due to the thermoregulation abilities of the homeotherms – while living in colder climates, they can adapt by reduced heat dispersion, heat production, and increased energy expenditure (5, 7). So, our body temperature would not change the same way as in poikilotherms.
Nevertheless, a lower core body temperature was proven to prolong life thanks to studies on the transgenic mice with higher hypothalamic temperatures leading to their core body temperature constant reduction by 0.5-0.6 °C (8). To obtain a similar result without genetic manipulation there is a simple method that can be used which is a calorie restriction diet such as the popular intermittent fasting regime (9). The impact of the core body temperature lowering calorie restriction diet on longevity was tested on mice and preliminary on humans. (10, 11). In humans, it was proven that indeed calorie restriction can lower body temperature (10), and in mice models, data reveals that constantly lower core body temperature correlates with prolonged lifespan (12). To sum up, a controlled, balanced calorie restriction diet was suggested to be the most effective and simple way to prolong lifespan and slow down aging by reducing body temperature.
Benefits and risks of cold water swimming
Researchers suggest that chronic cold exposure could be potentially harmful, whereas intermittent cold exposure results in health benefits but do not extend lifespan (13). But what about short shock-like exposures to cold? Cold water swimming, as an example, is a tradition in northern countries, and it was thoroughly researched in connection to health benefits. Numerous field studies come from Scandinavia and Eastern Europe on various topics related to cold water swimming, such as adaptation to the cold, changes in lipid metabolism, effects on the immune system, and hormonal balance. Recreational winter swimming is performed mostly in water temperatures between 10°C and 16°C for short periods and is becoming increasingly popular. This whole-body stressful condition done correctly and regularly can lead to adaptation to cold or even increased tolerance for stressors and body hardening (14). Studies have suggested that it has various health benefits such as fewer upper respiratory tract infections thanks to improved immune response, blood pressure lowering, increase of insulin sensitivity, and overall antidepressant effect, boosting the well-being. Nevertheless, cold water swimming is also a risky hobby because the rapid body warmth loss can lead to hypothermia, cardiac arrhythmia, hemostasis, unconsciousness, and even cardiac arrest and death. It is critical for winter swimming to be performed gradually and with proper preparation and acclimatization. It is suggested to start acclimatization by regular swimming in the summer months and continue through colder months in fall and into winter while avoiding extreme cold conditions for at least the first season of cold swimming. Each swimming session should be preceded and ended by some form of exercise activity such as jogging to maintain and restore the body temperature. To avoid injury or death, it should always be performed under supervision (15).
Sauna bathing
Extremely warm or cold temperature is considered a challenge and a stressor to human health and body homeostasis. Recent studies have proven that heat stress might be highly beneficial for human health (16). Finnish Kuopio Ischemic Heart Disease Risk Factor Study was held on a randomly selected sample of 3433 men aged 42 to 60 years who resided in Kuopio, Finland, and regularly having Finish sauna bathing sessions. The study reported that subjects who were sauna bathing more frequently had a reduced risk of sudden cardiac death, fatal coronary heart disease, fatal cardiovascular disease, and all-cause mortality (17). The same cohort was also checked for the prevalence of dementia and Alzheimer’s disease. The results concluded a strong inverse association between regular sauna bathing and the lower risk of dementia and Alzheimer’s disease. Moreover, sauna bathing, an activity that promotes relaxation and well-being, may be an intervention recommendable to prevent or slow down the development of memory diseases in healthy adults (18). There is also a proven beneficial impact of regular sauna bathing for the risk of respiratory infections, pneumonia, stroke, or venous thromboembolism. There is evidence that the lower risk of chronic and acute diseases due to frequent sauna bathing might be connected to the reduction in inflammation (19-23). Moderate heat shock could also induce hormetic response by means of promoting the activity of heat shock proteins (HSPs), which may extend lifespan (3). Taken together, the pleasure of frequent sauna bathing can prolong our life due to preventing many age-related diseases as well.
Temperature changes can prolong your life
Changing the core body temperature either by an internal way such as a calorie restriction diet or externally by extreme cold and hot exposure can benefit our health and longevity. Once implemented into the lifestyle, temperature tweaking can prevent cardiovascular diseases, infections, or neurodegeneration diseases. At the same time, it is a condition considered stressful to the body. It has to be applied correctly to avoid risks such as malnutrition during calorie restriction diet, hypothermia during cold water swimming, and overheating during sauna bathing. Planning to pursue any of these activities regularly should be first always consulted with a physician and in case of cold water swimming, the cardiologist as well. All the metabolic changes happening in the human body during core temperature alterations are not well understood yet and still need numerous studies to accept them as fully safe and healthy.
References
1. McKay CP. Requirements and limits for life in the context of exoplanets. Proc Natl Acad Sci U S A. 2014;111(35):12628-33.
2. Geneva, II, Cuzzo B, Fazili T, Javaid W. Normal Body Temperature: A Systematic Review. Open Forum Infect Dis. 2019;6(4):ofz032.
3. Lagisz M, Hector KL, Nakagawa S. Life extension after heat shock exposure: assessing meta-analytic evidence for hormesis. Ageing Res Rev. 2013;12(2):653-60.
4. Liu RK, Walford RL. Increased Growth and Life-span with Lowered Ambient Temperature in the Annual Fish, Cynolebias adloffi. Nature. 1966;212(5067):1277-8.
5. Conti B. Considerations on temperature, longevity and aging. Cell Mol Life Sci. 2008;65(11):1626-30.
6. Vaanholt LM, Daan S, Schubert KA, Visser GH. Metabolism and aging: effects of cold exposure on metabolic rate, body composition, and longevity in mice. Physiol Biochem Zool. 2009;82(4):314-24.
7. Ocobock C. Human energy expenditure, allocation, and interactions in natural temperate, hot, and cold environments. Am J Phys Anthropol. 2016;161(4):667-75.
8. Conti B, Sanchez-Alavez M, Winsky-Sommerer R, Morale MC, Lucero J, Brownell S, et al. Transgenic mice with a reduced core body temperature have an increased life span. Science. 2006;314(5800):825-8.
9. McCay CM, Crowell MF, Maynard LA. The Effect of Retarded Growth Upon the Length of Life Span and Upon the Ultimate Body Size: One Figure. The Journal of Nutrition. 1935;10(1):63-79.
10. Redman LM, Martin CK, Williamson DA, Ravussin E. Effect of caloric restriction in non-obese humans on physiological, psychological and behavioral outcomes. Physiol Behav. 2008;94(5):643-8.
11. Carrillo AE, Flouris AD. Caloric restriction and longevity: effects of reduced body temperature. Ageing Res Rev. 2011;10(1):153-62.
12. Keil G, Cummings E, de Magalhaes JP. Being cool: how body temperature influences ageing and longevity. Biogerontology. 2015;16(4):383-97.
13. Holloszy JO, Smith EK. Longevity of cold-exposed rats: a reevaluation of the "rate-of-living theory". J Appl Physiol (1985). 1986;61(5):1656-60.
14. Manolis AS, Manolis SA, Manolis AA, Manolis TA, Apostolaki N, Melita H. Winter Swimming: Body Hardening and Cardiorespiratory Protection Via Sustainable Acclimation. Curr Sports Med Rep. 2019;18(11):401-15.
15. Knechtle B, Waskiewicz Z, Sousa CV, Hill L, Nikolaidis PT. Cold Water Swimming-Benefits and Risks: A Narrative Review. Int J Environ Res Public Health. 2020;17(23).
16. Heinonen I, Laukkanen JA. Effects of heat and cold on health, with special reference to Finnish sauna bathing. Am J Physiol Regul Integr Comp Physiol. 2018;314(5):R629-R38.
17. Laukkanen T, Khan H, Zaccardi F, Laukkanen JA. Association between sauna bathing and fatal cardiovascular and all-cause mortality events. JAMA Intern Med. 2015;175(4):542-8.
18. Laukkanen T, Kunutsor S, Kauhanen J, Laukkanen JA. Sauna bathing is inversely associated with dementia and Alzheimer's disease in middle-aged Finnish men. Age Ageing. 2017;46(2):245-9.
19. Kunutsor SK, Khan H, Zaccardi F, Laukkanen T, Willeit P, Laukkanen JA. Sauna bathing reduces the risk of stroke in Finnish men and women: A prospective cohort study. Neurology. 2018;90(22):e1937-e44.
20. Kunutsor SK, Laukkanen T, Laukkanen JA. Frequent sauna bathing may reduce the risk of pneumonia in middle-aged Caucasian men: The KIHD prospective cohort study. Respir Med. 2017;132:161-3.
21. Kunutsor SK, Laukkanen T, Laukkanen JA. Sauna bathing reduces the risk of respiratory diseases: a long-term prospective cohort study. Eur J Epidemiol. 2017;32(12):1107-11.
22. Kunutsor SK, Laukkanen T, Laukkanen JA. Longitudinal associations of sauna bathing with inflammation and oxidative stress: the KIHD prospective cohort study. Ann Med. 2018;50(5):437-42.
23. Kunutsor SK, Makikallio TH, Khan H, Laukkanen T, Kauhanen J, Laukkanen JA. Sauna bathing reduces the risk of venous thromboembolism: a prospective cohort study. Eur J Epidemiol. 2019;34(10):983-6.
Article reviewed by
Close
Dr. Ana Baroni MD. Ph.D.
Scientific & Medical Advisor
Quality Garant
Ana has over 20 years of consultancy experience in longevity, regenerative and precision medicine. She has a multifaceted understanding of genomics, molecular biology, clinical biochemistry, nutrition, aging markers, hormones and physical training. This background allows her to bridge the gap between longevity basic sciences and evidence-based real interventions, putting them into the clinic, to enhance the healthy aging of people. She is co-founder of Origen.life, and Longevityzone. Board member at Breath of Health, BioOx and American Board of Clinical Nutrition. She is Director of International Medical Education of the American College of Integrative Medicine, Professor in IL3 Master of Longevity at Barcelona University and Professor of Nutrigenomics in Nutrition Grade in UNIR University.
DISCOVER
HealthyLongevity.guide
Professional science-based education
250+ Articles, video lectures, webinars
Community of 1000+ verified professionals
.jpg)
