Acrochorda (skin tags)

Acrochordons are 1 mm to 1 cm (rarely giant sized) papules that may or may not have stems. Their color ranges from skin color to dark brown. Although acrochordon development has been associated type 2 diabetes mellitus (DM), glucose intolerance, hyperinsulinemia, obesity, pregnancy, acromegaly, aging, colonic polyps and genetic predisposition, its cause has not been fully understood."

Source : BMC Dermatology, Volume 20, article number 14,

Acrochorda - more commonly known as 'skin tags' - are extremely common. It's estimated that half the human population develops one or more at some stage. They are generally benign and easily removed. There's some evidence that they tend to grow in skin areas which are regularly subjected to friction - but they also commonly occur in areas where there's very little, e.g. on the eyelids.

As the paper cited above states, they are also 'associated' with abnormal insulin levels - but an overall agreed description of their cause(s) is currently lacking.