This news release was based on a very preliminary four-week study of mice. But readers of the misleading headline — “Black tea may help with weight loss, too” — will assume that the results apply to humans.
The release attempts to quickly clarify the erroneous impression left by the headline, which is good. But then it later quotes a researcher who extrapolates far beyond what a mouse study can tell us when she says: “Our new findings suggest that black tea, through a specific mechanism through the gut microbiome, may also contribute to good health and weight loss in humans.”
Mice are not people, and the results reported here are very unlikely to apply to humans. We have consistently learned, through mounds of research that’s much more relevant to humans than this study, that there’s no single food or nutrient that yields sustainable weight loss in people.
Research that makes small incremental steps in improving our knowledge of the health benefits of various types of foods is useful. This study, done on mice and suggesting that black tea has “strong impact on the gut microbiome” needs to be contextualized in terms of its impact on human health.
The study is very preliminary; it provides little if any support for the suggestion that those who like black tea “may have a new reason to keep drinking it.” And yet the news release framing has already been parroted by numerous news outlets with headlines like these:
Men’s Health: Drinking Black Tea May Help You Lose Weight
There is no discussion of the costs of black, decaffeinated tea.
While one might argue that the cost of tea is relatively well known, remember that this was an animal study. We don’t know how much a person would have to drink in order to achieve the equivalent dosage for humans. The release could have clarified this point.
It’s disappointing that we are left without any idea of the magnitude of the findings. We are told merely that “the weights of the mice that were given green or black tea extracts dropped to the same levels as those of the mice that received the low-fat diet throughout the study.”
No potential harms of consuming black tea were mentioned. Black tea contains caffeine, which can cause a range of adverse effects in high doses.
Of course, the manuscript that’s the basis of the release specifies that the study tested decaffeinated black tea. However, the release doesn’t mention this. Clarifying this point would have been helpful.
Although we do get some detail on the quality of the study and the composition of the different comparator groups, the release never explains the limitations of animal research. Instead of emphasizing the long road to proving an equivalent effect in humans, the release repeatedly suggests the possibility of human application right now.
The funders of the study are disclosed and there don’t appear to be any obvious conflicts of interest.
The study was, in a sense, a comparison of alternatives but there were no mentions of any alternatives to reduce weight in mice, other than the two teas in question.
We think the release could have talked briefly about calorie balance as the most accepted way to avoid weight gain, and calorie restriction to encourage weight loss.
Black and green tea are widely available so mentioning that fact is unnecessary.
The release provides some background about previous research in this area and how the black tea hypothesis grew out of that previous research, a 2015 UCLA study.
It’s never justifiable to imply a human effect based entirely on mouse research. Moreover, the release further suggests that it’s already been proven that green tea induces weight loss — something that certainly has not been conclusively established.
Systematic, Criteria-Driven
The tale of two “negative” studies. Or, how spin is applied to make research findings look more impressive. A must read. https://johnmandrola.substack.com/p/the-tale-of-two-negative-studies
The @nytimes chose to interview one of the editors of the @AnnalsofIM (publisher of this paper) who "gushed with extraordinary glee: It’s huge! There are very few things that reduce your mortality by 30%."
Turns out coffee is not one of those few things despite all that glee. https://twitter.com/garyschwitzer/status/1533202075928215558
Comments
Please note, comments are no longer published through this website. All previously made comments are still archived and available for viewing through select posts.
Our Comments Policy
But before leaving a comment, please review these notes about our policy.
You are responsible for any comments you leave on this site.
This site is primarily a forum for discussion about the quality (or lack thereof) in journalism or other media messages (advertising, marketing, public relations, medical journals, etc.) It is not intended to be a forum for definitive discussions about medicine or science.
We will delete comments that include personal attacks, unfounded allegations, unverified claims, product pitches, profanity or any from anyone who does not list a full name and a functioning email address. We will also end any thread of repetitive comments. We don”t give medical advice so we won”t respond to questions asking for it.
We don”t have sufficient staffing to contact each commenter who left such a message. If you have a question about why your comment was edited or removed, you can email us at feedback@healthnewsreview.org.
There has been a recent burst of attention to troubles with many comments left on science and science news/communication websites. Read “Online science comments: trolls, trash and treasure.”
The authors of the Retraction Watch comments policy urge commenters:
We”re also concerned about anonymous comments. We ask that all commenters leave their full name and provide an actual email address in case we feel we need to contact them. We may delete any comment left by someone who does not leave their name and a legitimate email address.
And, as noted, product pitches of any sort – pushing treatments, tests, products, procedures, physicians, medical centers, books, websites – are likely to be deleted. We don”t accept advertising on this site and are not going to give it away free.
The ability to leave comments expires after a certain period of time. So you may find that you’re unable to leave a comment on an article that is more than a few months old.
You might also like