A study of older adults in Australia and the U.S. indicates that cholesterol levels that fluctuate significantly from year to year without a change in medication may someday help to identify those with a higher risk of developing dementia. In a six-year study of almost 10,000 adults in their 70s, researchers found people with stable cholesterol levels had a significantly lower risk of developing dementia or showing cognitive decline compared to those with fluctuating cholesterol levels.