One study of a small number of male mice is really not significant evidence. This is at best a pilot study.
Perhaps next you'll suggest that large clothes are causing obesity.
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Dr Hamid Farshchi, from The University of Nottingham’s School of Life Sciences, said: “Our results are very interesting. They show that the women drinking water after their main meal at lunch time over 24 weeks lost on average 1.16kg more than the women who drank diet drinks after their meal. We think that by drinking water instead of sweet-tasting diet drinks, the women may be adhering better to the weight loss diet because artificial sweeteners may increase desire for sweetened and more energy dense foods.
Source https://www.nottingham.ac.uk/news/pressreleases/2016/october...