I can’t answer about weight gain as I’ve never experienced weight gain being caused directly by insulin, but I do know that Novo Nordisk claims Levemir leads to less weight gain than Lantus. Whether this is true or just marketing propaganda, who knows. Personally I prefer Levemir because I can take it in split doses approximately every 12 hours without overlap, and adjust the dose to deal with anticipated stress, exercise/activity, eating more before bed that will cause higher insulin needs later, etc. For most people Levemir is not a 24-hour insulin, as taking it in 1-dose will result in a larger peak and it running out at about 16-20 hours. If you would like to take 1 shot a day you are likely better off with Lantus or Tresiba.
