Does aspartame have any effect on insulin production?

I think there was an article in one of the tabloids recently which implied that drinking diet soda might increase weight gain - I didn't pay too much attention to it to be honest as I assumed that it would simply be down to larger people offsetting a few calories with a low calorie drink.

But then a pal asked if I knew of anything in the literature that looks at the effect of aspartame on insulin production (I think in people with diabetes rather than the general population). I didn't.

Since I've not been working at Diabetes UK for almost a year and no longer do literature reviews and whatnot I'm perhaps a bit rusty, so feel free to join in and help us out :)

I did a very basic search on PubMed at http://ncbi.nlm.nih.gov/entrez so that it was only searching within papers that were reporting on work done in humans. Undoubtedly there will be umpteen million papers claiming doom and gloom about aspartame, based on work done in mice. That's not to discount that work and it may well be useful in pointing to interesting things to study, it's just I would avoid rushing to conclusions based on that.

And to be honest I'd avoid rushing to any conclusions anywhere along the line in this process.

So... I wanted to search for insulin aspartame (where these words appear in the title, keywords or abstract etc) and I wanted to filter the results so that only those articles relating to human were returned.

This scary long URL might do the trick http://www.ncbi.nlm.nih.gov/pubmed?term=%28%28%22aspartame%22[MeSH%20Terms]%20OR%20%22aspartame%22[All%20Fields]%29%20AND%20%28%22insulin%22[MeSH%20Terms]%20OR%20%22insulin%22[All%20Fields]%29%29%20AND%20%22humans%22[MeSH%20Terms]&cmd=DetailsSearch

Clicking on that will bring up 39 (at time of writing) abstracts and it will also populate the search box with the search terms, so these can be tweaked to suit.

Things I would look out for might include - teeny tiny studies where only a handful of people were involved, studies where the people didn't have diabetes or were unusual in their diabetes (newly diagnosed or perhaps people with Type 2 not yet on any medication etc), studies in people who consume an abnormally large volume of unsugared soft drinks and who also use other unsugared products heavily. Also see if any studies specifically mention insulin secretion or changes in insulin production and how this is measured.

That might be a place to start.