A large new Northwestern Medicine® study upends our understanding of vitamin E and ties the increasing consumption of supposedly healthy vitamin E-rich oils -- canola, soybean and corn – to the rising incidence of lung inflammation and, possibly, asthma.
The new study shows drastically different health effects of vitamin E depending on its form. The form of Vitamin E called gamma-tocopherol in the ubiquitous soybean, corn and canola oils is associated with decreased lung function in humans, the study reports. The other form of Vitamin E, alpha-tocopherol, which is found in olive and sunflower oils, does the opposite. It associated with better lung function.
“Considering the rate of affected people we found in this study, there could be 4.5 million individuals in the U.S. with reduced lung function as a result of their high gamma-tocopherol consumption,” said senior author Joan Cook-Mills, an associate professor of medicine in allergy/immunology at Northwestern University Feinberg School of Medicine.
This is the first study to show gamma-tocopherol is associated with worse lung function.
Cook-Mills presented her research in May at the Oxidants and Antioxidants in Biology World Congress. It was also published in the journal Respiratory Research.
Rates of asthma in the U.S. have been climbing in the last 40 years, coinciding with a switch in U.S. diets from lard and butter to soybean, canola and corn oils, which were thought to be healthier for the heart. Looking at other countries’ rates of asthma, Cook-Mills said those with significantly lower rates of asthma have diets high in olive and sunflower oils.
In the U.S., asthma prevalence (the percentage of people who have been diagnosed with asthma and still have asthma) was 8.4 percent in 2010, as reported by the U.S. Department of Health and Human Services Centers for Disease Control and Prevention.
In the U.S., the average blood plasma level of gamma-tocopherol is four or more times higher than those of European and Scandinavian countries that consume sunflower and olive oil, Cook-Mills noted.
“People in countries that consume olive and sunflower oil have the lowest rate of asthma and those that consume soybean, corn and canola oil have the highest rate of asthma,” Cook-Mills said. “When people consume alpha-tocopherol, which is rich in olive oil and sunflower oil, their lung function is better.”
The study examined 4,526 individuals from the Coronary Artery Risk Development in Young Adults Study (CARDIA). Cook-Mills had done previous allergy research in mice showing alpha-tocopherol decreased lung inflammation, protecting healthy lung function and gamma-tocopherol increased lung inflammation and airway hyperresponsiveness, a characteristic of asthma. She hypothesized that they might have similar effects in humans.
Cook-Mills examined the CARDIA results for individuals’ lung function tests at four intervals from baseline to 20 years and the type of tocopherol levels in their blood plasma at three intervals from baseline to 15 years. She found that a high level of gamma-tocoperol, 10 micromolar in the blood plasma, was associated with a 10 to 17 percent reduction in lung function. Micromolar is a measure of the amount of gamma-tocopherol per liter volume of blood plasma.
“The blood plasma showed how much they had acquired in their tissues,” Cook-Mills said. “You get vitamin E from your diet or supplements.”
In 2012 research, she identified a mechanism for gamma-tocopherol increasing lung inflammation: protein kinase C-alpha, which binds both forms of vitamin E. Alpha-tocopherol inhibits the action of the protein and gamma-tocopherol increases the action of the protein.
“A 10 percent reduction in lung function is like an asthmatic condition,” Cook-Mills said. “People have more trouble breathing. They take in less air, and it’s harder to expel. Their lungs have reduced capacity.”
People with asthma already have lower lung function, so if they have high gamma-tocopherol levels, they would have even more difficulty breathing, Cook-Mills said. The individuals in CARDIA with asthma and high gamma-tocopherol had the lowest lung function.
Other Northwestern authors on the paper include Michelle Marchese; Rajesh Kumar, M.D.; Kiang Liu; Laura Colangelo and Pedro Avila, M.D.
This study was supported by the National Heart, Lung and Blood Institute of the National Institutes of Health grant R-1 AT004837.
Marla Paul | Eurek Alert!
A promising target for kidney fibrosis
21.04.2017 | Brigham and Women's Hospital
Stem cell transplants: activating signal paths may protect from graft-versus-host disease
20.04.2017 | Technische Universität München
More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.
Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...
Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.
"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...
The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.
Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...
The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...
Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.
Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...
20.04.2017 | Event News
18.04.2017 | Event News
03.04.2017 | Event News
25.04.2017 | Earth Sciences
25.04.2017 | Life Sciences
25.04.2017 | Earth Sciences