An unexpected signal in several major dairy studies suggested that people who ate more ice cream sometimes had a lower risk of type 2 diabetes, a result scientists did not expect, and still cannot fully explain.
Ice cream is rarely associated with disease prevention. With its mix of sugar, saturated fat, and calories, it is generally viewed as a treat rather than a protective food.
That is why researchers were surprised when multiple large studies of dairy intake turned up a puzzling result: in some groups, people who reported eating more ice cream appeared to have a lower risk of developing type 2 diabetes.
The finding has appeared often enough to attract serious attention, even though scientists remain cautious about what it means.
Early Clues From Dairy Research
One of the first signs that the dairy story might be more complicated emerged in the early 2000s. Researchers analyzing a long-running cohort study of heart-disease risk factors found that dairy foods were generally associated with a lower risk of insulin-resistance syndrome, a precursor to diabetes, among overweight participants.
However, one detail hidden in the data stood out: consuming “dairy-based desserts” – a category overwhelmingly dominated by ice cream – was associated with dramatically reduced odds of developing the syndrome. The protective effect observed for the dessert was 2.5 times larger than the effect observed for regular milk.
This was not an isolated incident. In 2005, the Health Professionals Follow-up Study, a massive investigation tracking more than 41,000 U.S. men, yielded a similarly perplexing result. While the published paper heavily emphasized the benefits of low-fat dairy, the raw data showed that men who consumed ice cream two or more times a week had a noticeably lower relative risk of type 2 diabetes compared to those who ate it less than once a month. In related work, one researcher found that among people with diabetes, eating about half a cup of ice cream per day was associated with a lower risk of heart problems.
