sábado, 23 de março de 2019
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Pests and the plant defenses against them drive diversity in tropical rainforests
Date: March 14, 2019 Source: University of Utah Summary: Researchers have been baffled by tropical rainforest diversity for over a century; 650 different tree species can exist in an area covering two football fields, yet similar species never grow next to each other. It seems like it's good to be different than your neighbors, but why?
A group of caterpillars congregate on a leaf on an Inga tree species. Caterpillars can do extraordinary damage to tree leaves. Different species of Inga trees have various defenses against herbivore species. Some herbivores have adapted ways to overcome tree defenses.
Credit: Thomas Kursar
Researchers have been baffled by tropical rainforest diversity for over a century; 650 different tree species can exist in an area covering two football fields, yet similar species never grow next to each other. It seems like it's good to be different than your neighbors, but why?
To grow in a tropical rainforest is to engage in constant warfare. Plants battle for resources, such as sunlight, water and minerals. Similar tree species compete for resources in the same ways, so they may inhibit each other's growth. Plants also battle against herbivore pests. Related trees share the same pests and diseases -- if one gets it, the infestation can spread. Scientists have asked, "What is the primary driver in tropical forest diversity-competition for resources, or herbivore pests?"
For the first time, University of Utah biologists compared the two mechanisms in a single study.
The team analyzed how neighboring trees influence the growth and survival of nine coexisting species of the tree genus Inga in the Panama rainforest. They compared tree traits for resource acquisition, anti-herbivore defenses and the herbivores that live on the plants. They found that neighboring trees were basically the same in terms of acquiring resources, but had very different defenses and herbivores. Indeed, the defensive traits and shared pests impacted growth and survival, while resource acquisition traits had no effect on the plants' success. These findings indicate that anything impacting pest populations, such as climate change or habitat fragmentation, will have an impact on the health of the rainforest.
"Working in these hyper-diverse tropical rainforests makes it abundantly clear just how complex the web of interacting species really is. No species or individual lives in isolation. At all levels within the food chain species are competing with one another for precious resources and contributing a huge amount of their energy to defending themselves from the barrage of enemies they face, said Dale Forrister, doctoral candidate in the School of Biological Sciences at the University of Utah and lead author of the study. "We are excited about this study because it highlights some of the important ways these antagonistic interactions might influence tropical diversity."
This study published on March 14, 2019, in the journal Science.
It's a jungle out there
The team conducted their analysis over five years within a 50-hectare forest plot in Barro Colorado Island, Panama. The site has growth and survival data for over 423,000 trees from a previous long-term study. The researchers analyzed every individual tree sapling from the focal Inga species and calculated the similarity of their Inga neighbors' traits within a 10-meter "neighborhood." They measured four resource acquisition traits, five anti-herbivore defenses and recorded which herbivores were eating which plants.
Forrister developed a complicated model to determine how neighboring trees influence sapling growth and survival. They found that resource acquisition traits had no effect on survival, while defensive traits and herbivores had a big impact.
There are only so many ways to acquire resources. Defensive traits, however, are nearly endless. Plants and herbivores are in a constant arms race to outsmart each other. Plants develop traits to deter hungry mandibles, and herbivores adapt to deal with the leaf's defenses. The Inga genus has a quiver of anti-herbivore traits, including tiny hairs, nectar cups that attract pugnacious ant protectors, and most notably, leaves filled with poisonous compounds. Each Inga species can make hundreds or sometimes thousands of different toxins.
"People may think of a jungle like it's a giant salad bowl. It should be paradise for pests because they're surrounded by leaves. But plants have an infinite number of defense combinations -- half the weight of a young leaf is poison," said Phyllis Coley, Distinguished Professor of Biology at the University of Utah, research affiliate at the Smithsonian Tropical Research Institute and co-author of the study. "As a consequence of the diversity of defenses, each species of herbivore can only eat a few species of plants that they have adaptations for."
Closely related plants have similar defensive traits, and therefore similar pests. If a plant differs from its neighbor in terms of defenses, their herbivores aren't a threat, Coley continued. "You'll have your own herbivores, but at least you won't have all the critters in the neighborhood eating you."
Confounding chemical compounds
Plant toxins are the most important weapons for tropical plants, but testing the similarity of each species' chemicals proved problematic. Over five years, the researchers collected leaf samples in the field, dried them in a makeshift desiccator suitcase (no easy feat in 100 percent humidity) and then brought them to the U for analysis. Using high performance liquid chromatography, they separated all of the distinct compounds inside the leaves. However, only 4 percent of the Inga compounds were known to science. So, the team got creative and came up with a new metric. They used a mass spectrometer to determine the chemical structure of each compound, and established that compounds with similar structures were likely affecting herbivores in a similar way.
"Metabolomics, a relatively new field of science, offers scientist a powerful new toolbox for examining the vast amount of chemical diversity that exists out there. Chemicals play a huge role in nature, from defenses to communication they are the medium by which species interact. Being able to quantify this in a meaningful way provides a truly unique perspective," said Forrister.
But do the herbivores "care" about the traits the team was measuring and do Inga species with similar traits share herbivores? To test this, they collected caterpillars that were eating Inga leaves and sequenced their DNA to classify each as species A, species B, etc. They were unable to name the species because most of the caterpillars were new to science. They cataloged which herbivores were eating which plants, correlated the suite of compounds in the plants and inferred which plant species shared herbivore communities.
Both old-school field research and modern techniques were indispensable to this project's success.
"Despite state-of-the-art laboratory facilities, there's no substitute for spending months and months in the rainforest," said Coley. "It took us several years to collect data, and samples of leaves and herbivores. It's hot, humid and buggy, but attempting to understand the diversity of species is a biologist's dream."
The study reveals the significant role of herbivores in driving diversity in tropical ecosystems, with stark implications -- the loss of those populations could have catastrophic consequence on these important habitats.
"If climate change continues to increase the length of the dry season in the Americas, then the dynamics of the herbivore populations will change as well," said Coley. "That could have implications down the road."
Story Source:
Materials provided by University of Utah. Note: Content may be edited for style and length.
Journal Reference:
Dale L. Forrister, María-José Endara, Gordon C. Younkin, Phyllis D. Coley, Thomas A. Kursar. Herbivores as drivers of negative density dependence in tropical forest saplings. Science, 2019; 363 (6432): 1213 DOI: 10.1126/science.aau9460
Cite This Page:
University of Utah. "Pests and the plant defenses against them drive diversity in tropical rainforests." ScienceDaily. ScienceDaily, 14 March 2019. <www.sciencedaily.com/releases/2019/03/190314151548.htm>.
Higher egg and cholesterol consumption hikes heart disease and early death risk
Date: March 15, 2019
Source: Northwestern University
Summary:
Cancel the cheese omelet. A large, new study of nearly 30,000 people reports adults who ate more eggs and dietary cholesterol had a significantly higher risk of cardiovascular disease and death from any cause. People need to consume lower amounts of cholesterol to have a lower risk of heart disease, the study authors said.
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Scientists identify compounds in coffee which may inhibit prostate cancer
Date: March 18, 2019 Source: European Association of Urology Summary: For the first time, scientists have identified compounds found in coffee which may inhibit the growth of prostate cancer. This is a pilot study, carried out on drug-resistant cancer cells in cell culture and in a mouse model; it has not yet been tested in humans.
For the first time, scientists have identified compounds found in coffee which may inhibit the growth of prostate cancer. This is a pilot study, carried out on drug-resistant cancer cells in cell culture and in a mouse model; it has not yet been tested in humans. This work is presented at the European Association of Urology congress in Barcelona, after publication in the peer-reviewed journal The Prostate.
Coffee is a complex mixture of compounds which has been shown to influence human health in both positive and negative ways. There is increasing evidence that drinking certain types of coffee is associated with a reduction in incidence of some cancers, including prostate cancers. Now Japanese scientists have studied the effects of two compounds found in coffee, kahweol acetate and cafestol, on prostate cancer cells and in animals, where they were able to inhibit growth in cells which are resistant to common anti-cancer drugs such as Cabazitaxel.
The researchers initially tested six compounds, naturally found in coffee, on the proliferation of human prostate cancers cells in vitro (i.e. in a petri-dish). They found that cells treated with kahweol acetate and cafestol grew more slowly than controls. They then tested these compounds on prostate cancer cells which had been transplanted to mice (16 mice). 4 mice were controls, 4 were treated with kahweol acetate, 4 with cafestol, with the remaining mice being treated with a combination of kahweol acetate and cafestol.
Study leader, Dr Hiroaki Iwamoto (Department of Integrative Cancer Therapy and Urology, Kanazawa University Graduate School of Medical Science, Japan, first author of the study) said:
"We found that kahweol acetate and cafestol inhibited the growth of the cancer cells in mice, but the combination seemed to work synergistically, leading to a significantly slower tumour growth than in untreated mice. After 11 days, the untreated tumours had grown by around 3 and a half times the original volume (342%), whereas the tumours in the mice treated with both compounds had grown by around just over one and a half (167%) times the original size.
It is important to keep these findings in perspective. This is a pilot study, so this work shows that the use of these compounds is scientifically feasible, but needs further investigation; it does not mean that the findings can yet be applied to humans. We also found the growth reduction in transplanted tumour cells, rather than in native tumour cells. What it does show is that these compounds appear to have an effect on drug resistant cells prostate cancer cells in the right circumstances, and that they too need further investigation. We are currently considering how we might test these findings in a larger sample, and then in humans."
Kahweol acetate and cafestol are hydrocarbons, naturally found in Arabica coffee. The coffee-making process has been found to affect whether these compounds remain in coffee after brewing (as with espresso), or whether they are stripped out (as when filtered).
Professor Atsushi Mizokami (Department of Integrative Cancer Therapy and Urology, Kanazawa University Graduate School of Medical Science, Japan) added:
"These are promising findings, but they should not make people change their coffee consumption. Coffee can have both positive and negative effects (for example it can increase hypertension), so we need to find out more about the mechanisms behind these findings before we can think about clinical applications. However, if we can confirm these results, we may have candidates to treat drug-resistant prostate cancer."
In an independent comment, Professor Zoran Culig (Professor of Experimental Urology, Medical University of Innsbruck) said:
"These are interesting findings. I would expect that those initial results will motivate researchers to use more recently developed models, such as patient-derived xenografts which express the androgen receptor. Such experiments will likely provide a definitive answer as to future perspective of this kind of treatment."
Story Source:
Materials provided by European Association of Urology. Note: Content may be edited for style and length.
Journal Reference:
Hiroaki Iwamoto, Kouji Izumi, Ariunbold Natsagdorj, Renato Naito, Tomoyuki Makino, Suguru Kadomoto, Kaoru Hiratsuka, Kazuyoshi Shigehara, Yoshifumi Kadono, Kazutaka Narimoto, Yohei Saito, Kyoko Nakagawa‐Goto, Atsushi Mizokami. Coffee diterpenes kahweol acetate and cafestol synergistically inhibit the proliferation and migration of prostate cancer cells. The Prostate, 2018; 79 (5): 468 DOI: 10.1002/pros.23753
Cite This Page:
European Association of Urology. "Scientists identify compounds in coffee which may inhibit prostate cancer." ScienceDaily. ScienceDaily, 18 March 2019. <www.sciencedaily.com/releases/2019/03/190318111955.htm>.
Inflammation links heart disease and depression
Date: March 18, 2019
Source: University of Cambridge
Summary:
People with heart disease are more likely to suffer from depression, and the opposite is also true. Now, scientists believe they have identified a link between these two conditions: inflammation -- the body's response to negative environmental factors, such as stress.
People with heart disease are more likely to suffer from depression, and the opposite is also true. Now, scientists believe they have identified a link between these two conditions: inflammation -- the body's response to negative environmental factors, such as stress.
See more at:https://www.sciencedaily.com/releases/2019/03/190318222147.htm
A nutty solution for improving brain health
Solutions for an ageing population
Date: March 19, 2019 Source: University of South Australia Summary: Long-term, high nut consumption could be the key to better cognitive health in older people according to new research.
Long-term, high nut consumption could be the key to better cognitive health in older people according to new research from the University of South Australia.
In a study of 4822 Chinese adults aged 55+ years, researchers found that eating more than 10 grams of nuts a day was positively associated with better mental functioning, including improved thinking, reasoning and memory.
Lead researcher, UniSA's Dr Ming Li, says the study is the first to report an association between cognition and nut intake in older Chinese adults, providing important insights into increasing mental health issues (including dementia) faced by an ageing population.
"Population aging is one of the most substantial challenges of the twenty-first century. Not only are people living longer, but as they age, they require additional health support which is placing unprecedented pressure on aged-care and health services," Dr Li says.
"In China, this is a massive issue, as the population is ageing far more rapidly than almost any other country in the world.
"Improved and preventative health care -- including dietary modifications -- can help address the challenges that an aging population presents.
"By eating more than 10 grams (or two teaspoons) of nuts per day older people could improve their cognitive function by up to 60 per cent- compared to those not eating nuts -- effectively warding off what would normally be experienced as a natural two-year cognition decline."
China has one of the fastest growing aging populations. In 2029, China's population is projected to peak at 1.44 billion, with the ratio of young to old dramatically imbalanced by the rising ranks of the elderly. By 2050, 330 million Chinese will be over age 65, and 90.4 million will be over age 80, representing the world's largest population of this most elderly age group.
More broadly, the World Health Organization says that by 2020, the number of people aged 60 years and older will outnumber children younger than five years old.
The UniSA study analysed nine waves of China Health Nutrition Survey data collected over 22 years, finding that 17 per cent of participants were regular consumers of nuts (mostly peanuts). Dr Li says peanuts have specific anti-inflammatory and antioxidant effects which can alleviate and reduce cognitive decline.
"Nuts are known to be high in healthy fats, protein and fibre with nutritional properties that can lower cholesterol and improve cognitive health," Dr Li says.
"While there is no cure for age-related cognition decline and neurogenerative disease, variations in what people eat are delivering improvements for older people."
The World Health Organization estimates that globally, the number of people living with dementia is at 47 million.
By 2030, this is projected to rise to 75 million and by 2050, global dementia cases are estimated to almost triple. China has the largest population of people with dementia.
"As people age, they naturally experience changes to conceptual reasoning, memory, and processing speed. This is all part of the normal ageing process," Dr Li says
"But age is also the strongest known risk factor for cognitive disease. If we can find ways to help older people retain their cognitive health and independence for longer -- even by modifying their diet -- then this absolutely worth the effort."
Story Source:
Materials provided by University of South Australia. Note: Content may be edited for style and length.
Journal Reference:
Ming Li, Z. Shi. A Prospective Association of Nut Consumption with Cognitive Function in Chinese Adults Aged 55 _ China Health and Nutrition Survey. The journal of nutrition, health & aging, 2018; 23 (2): 211 DOI: 10.1007/s12603-018-1122-5
Cite This Page:
University of South Australia. "A nutty solution for improving brain health: Solutions for an ageing population." ScienceDaily. ScienceDaily, 19 March 2019. <www.sciencedaily.com/releases/2019/03/190319100803.htm>.
Go for a run or eat chocolate: A choice dictated by the cannabinoid receptors
Date: March 19, 2019 Source: INSERM (Institut national de la santé et de la recherche médicale) Summary: A study reveals that the cannabinoid type 1 (CB1) receptors play an essential role in the choice between running and eating chocolatey food.
Physical inactivity is a common factor in lifestyle diseases -- and one that is often linked to the excessive consumption of fatty and/or sugary foods. The opposite scenario of excessive physical activity at the expense of caloric intake can also be harmful, as cases of anorexia nervosa illustrate. These data therefore point to the crucial need to research the neurobiological processes that control the respective motivations for exercise and food intake. A study by Inserm and CNRS researchers published on March 7, 2019 in JCI Insight reveals that the cannabinoid type 1 (CB1) receptors play an essential role in the choice between running and eating chocolatey food.
The authors of this paper had previously reported that the cannabinoid type-1 (CB1) receptors, present on several types of neurons, play a key role in performance during physical activity in mice. A conclusion based on the performances achieved by animals with free access to an exercise wheel -- a model in which it was not possible to distinguish the mechanism involved (motivation, pleasure...). Given that the motivation for a reward can only be estimated by measuring the efforts that the individual -- whether human or animal -- is prepared to make to get that reward, the researchers devised a model in which each access to the wheel was conditional on a prior effort. This involved the animal repeatedly introducing its snout into a recipient, an essential prerequisite for unlocking the wheel. After a training period during which the level of effort required to unlock the wheel remained the same, the mice were confronted with a test in which the effort required was gradually increased. When exposed to this test, the mice lacking CB1 receptors showed an 80 % deficit in the maximum effort they were prepared to make to unlock the wheel, and without a decrease in performance during their access to it. This finding indicates that the CB1 receptors play a major role in controlling motivation for exercise. The use of other genetically-modified mice also enabled the researchers to demonstrate that these CB1 receptors controlling motivation for exercise are located on GABAergic neurons.
The researchers then examined whether the CB1 receptors in the GABAergic neurons control the motivation for another reward: chocolatey food (like humans, mice love it even when they are otherwise well-fed). While the CB1 receptors also play a role in motivation for food -- albeit to a lesser extent than in motivation for exercise -- the CB1 receptors located on the GABAergic neurons are not implicated in the motivation for eating chocolatey food.
In our daily life, we are faced with an ongoing choice between various rewards. A fact which has encouraged the researchers to develop a model in which following a learning period the mice had the choice -- in return for the efforts described above -- between exercise and chocolatey food. The motivation for exercise was greater than that for chocolatey food, with the exception of the mice lacking CB1 -- whether generally or just on GABAergic neurons -- whose preference was for the food.
In addition to these findings indicating that the cannabinoid receptor is essential for the motivation for exercise, this study opens up avenues for researching the neurobiological mechanisms behind pathological increases in this motivation. One illustration is provided by anorexia nervosa which often combines the decreased motivation to eat with an increased motivation to exercise.
Story Source:
Materials provided by INSERM (Institut national de la santé et de la recherche médicale). Note: Content may be edited for style and length.
Journal Reference:
Carolina Muguruza, Bastien Redon, Giulia R. Fois, Imane Hurel, Amandine Scocard, Claire Nguyen, Christopher Stevens, Edgar Soria-Gomez, Marjorie Varilh, Astrid Cannich, Justine Daniault, Arnau Busquets-Garcia, Teresa Pelliccia, Stéphanie Caillé, François Georges, Giovanni Marsicano, Francis Chaouloff. The motivation for exercise over palatable food is dictated by cannabinoid type-1 receptors. JCI Insight, 2019; 4 (5) DOI: 10.1172/jci.insight.126190
Cite This Page:
INSERM (Institut national de la santé et de la recherche médicale). "Go for a run or eat chocolate: A choice dictated by the cannabinoid receptors." ScienceDaily. ScienceDaily, 19 March 2019. <www.sciencedaily.com/releases/2019/03/190319121721.htm>.
Prescribing healthy food in Medicare/Medicaid is cost effective, could improve health
Date: March 19, 2019
Source: Tufts University, Health Sciences Campus
Summary:
A team of researchers modeled the health and economic effects of healthy food prescriptions in Medicare and Medicaid. The study finds that health insurance coverage to offset the cost of healthy food for Medicare and/or Medicaid participants would be highly cost effective after five years and improve health outcomes.
See more at: https://www.sciencedaily.com/releases/2019/03/190319163532.htm
Active substance from plant slows down aggressive eye cancer
Date: March 20, 2019 Source: University of Bonn Summary: An active substance that has been known for 30 years could unexpectedly turn into a ray of hope against eye tumors. This is shown by a new study. The plant leaves of which contain the tested substance is anything but rare: At Christmas time you can find it in every well-assorted garden center.
The leaves of the coralberry (Ardisia crenata) contain the natural substance FR900359, which may be suitable as a drug against eye cancer.
Credit: Volker Lannert/Uni Bonn
An active substance that has been known for 30 years could unexpectedly turn into a ray of hope against eye tumors. This is shown by a study conducted by researchers from the Universities of Bonn and Magdeburg together with US colleagues. The results are published in the journal "Science Signaling." The plant leaves of which contain the tested substance is anything but rare: At Christmas time you can find it in every well-assorted garden center.
The coralberry decorates many German living rooms during the winter months. At this time it forms bright red fruits, which make it a popular ornamental plant. The plant, originally from Korea, is surprisingly resistant to insect attack: Its leaves contain bacteria that produce a natural insecticide -- a toxin with the cryptic name FR900359, abbreviated FR.
This toxin could soon become a star in a completely different field: as a potential drug against uveal melanoma, the most common and aggressive variant of eye cancer. FR has been the focus of pharmaceutical research for some time now: "The substance inhibits an important group of molecules in the cells, the Gq proteins," explains Prof. Dr. Evi Kostenis from the Institute of Pharmaceutical Biology at the University of Bonn.
Gq proteins have a similar function in the cell as a city's emergency control center: When the control center receives a call, it informs the police, ambulance and fire brigade as required. Gq proteins, on the other hand, can be activated by certain control signals. In their activated form, they switch different metabolic pathways on or off. However, the cell should not permanently change its behavior. The Gq proteins therefore inactivate themselves after a short time.
In uveal melanoma, however, a tiny mutation prevents two important Gq proteins from returning to their inactive state. They thus remain permanently active -- this is as if the control center were constantly sending emergency vehicles to the source of the fire, even though the fire has been extinguished for days. Due to this malfunction, cells harboring this mutation begin to divide uncontrollably.
"FR can stop this division activity," says Kostenis. "That's something no one would have expected." It has been known for some time that FR can prevent the activation of Gq proteins. The substance "clings" to the proteins and ensures that they remain in their inactive form. Common understanding was that FR ignores any Gq proteins that have already been activated. "Therefore, it seemed impossible for the substance to be effective in mutated and thus permanently active Gq proteins," emphasizes Dr. Evelyn Gaffal.
A firm grip on the cancer causing protein
Gaffal recently moved from Bonn to the University of Magdeburg. Her research there includes strategies for combating skin cancer. "We also used FR in our experiments and were surprised to find that it suppresses the proliferation of cancer cells," she explains. Scientists now also know why this is so: The mutated Gq proteins also seem to occasionally revert into their inactive form. As soon as this happens, FR900359 intervenes and gets a firm grip on the molecule. As a result, over time, more and more Gq proteins are successively withdrawn from their activated state for good.
FR has already proven its effectiveness in cell cultures and in experiments with mice suffering from cancer. But there are still a few hurdles to overcome before application in humans becomes feasible. Above all, the substance must reach the tumor cells precisely, without hitting other tissues. "Gq proteins assume vital functions practically everywhere in the body," explains Prof. Kostenis. "If we want FR to kill only the tumor cells, we have to get the drug right there. However, this is a challenge that many other chemotherapies also have to deal with."
FR was isolated for the first time 30 years ago by Japanese researchers. Another 25 years would pass before its biological mode of action was described -- by none other than the research groups led by Professor Gabriele M. König and Professor Evi Kostenis at the Institute of Pharmaceutical Biology of the University of Bonn. This work now forms the basis for a research group of the German Research Foundation (DFG) on the group of G proteins and the possibility of their pharmacological manipulation.
Story Source:
Materials provided by University of Bonn. Note: Content may be edited for style and length.
Journal Reference:
Suvi Annala, Xiaodong Feng, Naveen Shridhar, Funda Eryilmaz, Julian Patt, JuHee Yang, Eva M. Pfeil, Rodolfo Daniel Cervantes-Villagrana, Asuka Inoue, Felix Häberlein, Tanja Slodczyk, Raphael Reher, Stefan Kehraus, Stefania Monteleone, Ramona Schrage, Nina Heycke, Ulrike Rick, Sandra Engel, Alexander Pfeifer, Peter Kolb, Gabriele König, Moritz Bünemann, Thomas Tüting, José Vázquez-Prado, J. Silvio Gutkind, Evelyn Gaffal, Evi Kostenis. Direct targeting of Gαq and Gα11 oncoproteins in cancer cells. Science Signaling, 2019; 12 (573): eaau5948 DOI: 10.1126/scisignal.aau5948
Cite This Page:
University of Bonn. "Active substance from plant slows down aggressive eye cancer." ScienceDaily. ScienceDaily, 20 March 2019. <www.sciencedaily.com/releases/2019/03/190320102213.htm>.
Drinking hot tea linked with elevated risk of esophageal cancer
Date: March 20, 2019 Source: Wiley Summary: Previous studies have revealed a link between hot tea drinking and risk of esophageal cancer, but until now, no study has examined this association using prospectively and objectively measured tea drinking temperature. A new study achieved this by following 50,045 individuals aged 40 to 75 years for a median of 10 years.
Previous studies have revealed a link between hot tea drinking and risk of esophageal cancer, but until now, no study has examined this association using prospectively and objectively measured tea drinking temperature. A new International Journal of Cancerstudy achieved this by following 50,045 individuals aged 40 to 75 years for a median of 10 years.
During follow-up, 317 new cases of esophageal cancer were identified. Compared with drinking less than 700 ml of tea per day at less than 60°C, drinking 700 ml per day or more at a higher temperature (60°C or higher) was associated with a 90 percent higher risk of esophageal cancer.
"Many people enjoy drinking tea, coffee, or other hot beverages. However, according to our report, drinking very hot tea can increase the risk of esophageal cancer, and it is therefore advisable to wait until hot beverages cool down before drinking," said lead author Dr. Farhad Islami, of the American Cancer Society.
Story Source:
Materials provided by Wiley. Note: Content may be edited for style and length.
Journal Reference:
Farhad Islami, Hossein Poustchi, Akram Pourshams, Masoud Khoshnia, Abdolsamad Gharavi, Farin Kamangar, Sanford M. Dawsey, Christian C. Abnet, Paul Brennan, Mahdi Sheikh, Masoud Sotoudeh, Arash Nikmanesh, Shahin Merat, Arash Etemadi, Siavosh Nasseri Moghaddam, Paul D. Pharoah, Bruce A. Ponder, Nicholas E. Day, Ahmedin Jemal, Paolo Boffetta, Reza Malekzadeh. A prospective study of tea drinking temperature and risk of esophageal squamous cell carcinoma. International Journal of Cancer, 2019; DOI: 10.1002/ijc.32220
Cite This Page:
Wiley. "Drinking hot tea linked with elevated risk of esophageal cancer." ScienceDaily. ScienceDaily, 20 March 2019. <www.sciencedaily.com/releases/2019/03/190320102028.htm>.