Type 2 diabetes is a highly prevalent disease that promotes multiple conditions, including stroke, heart attacks, kidney failure and blindness. Physical exercise is known to prevent type 2 diabetes, and a related condition named insulin resistance.
On the other hand, exercise also induces formation of free radicals, a form of very active oxygen, producing oxidative stress, which, if it persists for long periods of time, is commonly thought to be harmful. Accordingly, athletes, as well as non-athletes, consume antioxidant supplements to ameliorate the presumably harmful side-effects of oxidative stress. Moreover, a significant percentage of the general population uses antioxidant supplements on a daily basis in hopes to prevent other kinds of oxidative tissue damage and thereby improve health and longevity. The most commonly used anti-oxidants are vitamins C and E.
A study published today in the "Proceedings of the National Academy of Sciences" (PNAS) suggests that vitamin C and E supplements may actually be harmful, at least in regards to diabetes risk and glucose metabolism. According to this study, the health-promoting effects of exercise require the formation of oxidative stress during sports and if this is blocked, some of these effects do not occur. In the particular study, the intake of antioxidants during a four-week exercise training class abolished the effects of exercise to improve insulin sensitivity and glucose metabolism which would help prevent diabetes, while those individuals not taking the antioxidants had major benefits in terms of metabolism from exercise.
Dr. Michael Ristow, lead-author of the study which was published by a team of researchers from Leipzig and Jena Universities (both Germany) and Harvard Medical School, points out: "Exercise causes repeated boosts of free radicals, which - according to our results - induce a health-promoting adaptive response in humans. Subsequently, our body activates molecular defense systems against stress, and metabolizes carbohydrates more efficiently, both of which prevents diabetes, and possibly other diseases. Blocking these boosts of free radicals by antioxidants accordingly blocks the health promoting effects of exercise." He further says that "short-term doses of free radicals may act like a vaccine, helping the body to defend itself from chronic stressors more efficiently by inducing a long-term adaptive response".
Dr. C. Ronald Kahn, a collaborating author from the Joslin Diabetes Center and Harvard Medical School, noted: "This is a very important study for the millions of people at risk for type 2 diabetes. Exercise is a proven way to improve insulin action and reduce diabetes risk, but clearly this beneficial effect can be largely blocked by taking these very commonly used vitamin supplements. We need larger studies to fully assess this effect, but in the meantime, individuals at risk for diabetes and maybe even some with type 2 diabetes itself, need to think carefully about the use of these vitamin supplements, especially if they exercise regularly to improve there health."Original Publication:
Prof. Dr. C. Ronald Kahn, M.D., Joslin Diabetes Center, Harvard Medical School, Boston, MA, USA; tel. +1-617-732-2635, e-mail: email@example.com
Further reports about: > Diabetes > Insulin > Medical Wellness > Nutrition > PNAS > Universität Harvard > Vitamin D > antioxidant supplements > antioxidants > blindness > diabetes risk > exercise > free radicals > glucose metabolism > heart attacks > kidney failure > oxidative stress > stroke > type 2 diabetes
Tracking movement of immune cells identifies key first steps in inflammatory arthritis
23.01.2017 | Massachusetts General Hospital
Team discovers how bacteria exploit a chink in the body's armor
20.01.2017 | University of Illinois at Urbana-Champaign
For the first time ever, a cloud of ultra-cold atoms has been successfully created in space on board of a sounding rocket. The MAIUS mission demonstrates that quantum optical sensors can be operated even in harsh environments like space – a prerequi-site for finding answers to the most challenging questions of fundamental physics and an important innovation driver for everyday applications.
According to Albert Einstein's Equivalence Principle, all bodies are accelerated at the same rate by the Earth's gravity, regardless of their properties. This...
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
24.01.2017 | Earth Sciences
24.01.2017 | Life Sciences
24.01.2017 | Physics and Astronomy