Scientists are warning that US dementia cases are projected to double in the next 35 years, with women, Black people and those over 75 facing the highest risks due to aging, unhealthy diets, health disparities and genetic factors. Their research in the journal Nature Medicine also underlines that the risk of developing dementia after the age of 55 is 42%, which is more than double the rates measured by previous studies. The condition causes a decline in memory, concentration and judgment.