Sense about Science ? equipping people to make sense of science and evidence
For the record
"Heart danger in diet drinks"
Dr Iain Lang, Consultant in Public Health, NHS Devon, and Senior Lecturer in Public Health, at the Peninsula College of Medicine and Dentistry responds:
"The researchers who carried out this work are very clear about their findings: first, that their results show an association between drinking diet soft drinks and strokes and heart attacks; second, that more research is needed before we can draw any conclusions about the health effects of these drinks. It's worth noting that the relationship they found was only related to diet soft drinks: not regular soft drinks, and not light diet soft drinks, and they acknowledge there are uncertainties about why this is.”
“There are a number of difficulties in interpreting findings like this. One relates to whether the people who participated in the research are similar enough to other groups to make the findings applicable elsewhere. For example, a study carried out in one neighbourhood of one town or city might generate results that would not be found elsewhere. In this study the people who participated were older people living in New York City; more than half of them were Hispanic and almost 23% were black. This group of urban Americans are likely to be quite different from many people in the UK - different in terms of background, of habits, of diet, and in various other ways - so what the research suggests about them might not hold true elsewhere.”
“A second difficulty relates to whether the findings could be explained by some other factor. At one stage we thought drinking alcohol caused lung cancer, because people who drink regularly are more likely to develop lung cancer - but then it was discovered that people who drink alcohol regularly are more likely to smoke as well, and it was smoking that made this group more likely to get lung cancer. The same goes here: it may not be that drinking diet soft drinks has any effect but rather that something else about this group of people is producing these results.”
“Findings like these should always be treated with caution, tempting though it is to jump to conclusions about what they show, or seem to show. Further studies on this topic are needed to give us a better understanding of what is going on here."
Document type: For The Record
Published: 1 February 2012