RealClearScience reports the very odd findings of a study done at Harvard. The results were, to say the least, counterintuitive. The research was originally published in the journal Scientific Reports.
Researchers at Harvard University discovered that perceived sugar intake affects blood sugar levels in people with Type 2 diabetes more than actual sugar intake, at least temporarily.
They found that participants who thought they were drinking the high-sugar variant had significantly elevated blood sugar levels during the monitoring period compared to those who thought they were drinking the low-sugar variant.
In reality all subjects drank the same sweetened beverage. What changed was the information given to them concerning how much sugar, if any, it supposedly contained.
The authors warn Type 2 diabetes sufferers:
This sort of psychological trickery cannot treat Type 2 diabetes on its own. A diabetic could not, on a prolonged basis, trick themselves out of diabetes.
As far as I can determine, the authors have no data showing this last statement is true. I believe they are wisely protecting themselves against lawsuits brought by the heirs of people who die after trying to "psych" themselves healthy with positive thoughts, instead of taking their meds.