Despite popular belief, antioxidants could be doing more harm to health than good reported the Daily Mail. Antioxidants are thought to be beneficial as they neutralise
Despite popular belief, antioxidants could be doing more harm to health than good reported the Daily Mail . Antioxidants are thought to be beneficial as they neutralise free radical molecules and many disorders “are wholly or partly blamed on free radicals”, the newspaper explained on August 10 2007. Free radicals are highly reactive, unstable molecules that cause atoms in the cells of the body to lose an electron; this process, called oxidative stress, causes damage.
However, the Daily Mail said that scientists have found that too much antioxidant can also damage cells. Researchers found that “high levels of antioxidants could make atoms gain electrons, in a process called reductive stress – causing untold damage” the newspaper reported. Yet, it is too soon to conclude that antioxidants are bad for health
The newspaper stories are based on the reports of research carried out in mice. The study underlying these stories was well-conducted, although we must be cautious about extrapolating findings from animal studies directly to humans. The findings are interesting and should be the basis for further research into the characteristics of degenerative diseases in humans. Importantly the study is about antioxidants occurring naturally in cells and does not consider the effects of ingested antioxidants, for example, from fruit and vegetables.
Namakkal Rajasekaran and colleagues from the University of Utah School of Medicine and other medical institutions in the US conducted this research and it was published in the peer-reviewed medical journal, Cell .
This study is a laboratory-based animal study carried out in mice. A genetic mutation that occurs in humans and is known to be linked to degenerative diseases, such as cardiomyopathy (weakness and damage of heart muscle), was inserted into the DNA of the mice. This mutation causes cells to produce a malformed protein and in this experiment, the mice were bred so that the mutation appeared in heart tissue. The mutation caused the heart tissue to overproduce this malformed protein and this led to a cardiomyopathy-like disease in the mice.
The mice were bred in different groups, one group of mice had a high level of malformed protein in the heart tissue and the other group had a lower amount of malformed protein. The researchers then compared the disease characteristics between the two groups of mice with the human gene inserted into their DNA with normal mice.
The following three findings are most relevant to this story:
The researchers recognise that reductive stress is an important metabolic step in of this type of cardiomyopathy. They say that this reductive stress "might also represent a common mechanism" in the disease chain for several degenerative diseases.
This research appears to have been well conducted and its findings should be a starting point for further research into the cellular effects of diseases such as cardiomyopathy. As the study was conducted in mice, we should be cautious about extending the findings directly to humans, where metabolism is quite different.
With these limitations in mind, it is too soon to conclude that antioxidants are bad for health.