A British study has found brain functions including memory can begin declining as early as the mid-forties and possibly earlier. This decline includes memory, reasoning and comprehension abilities. The results come from a 10-year study involving more than 7,000 British government workers. This study comes as a surprise to the medical community as researchers had originally expected to see no decline in cognitive functioning in those 45 to 49. They instead found a modest decline in mental reasoning in both males and females in this age range. As they evaluated older individuals, they found the cognitive declines even greater. Although, one third of those studied between the ages of 45 and 70 showed no loss in cognitive function and thus, not all aging individuals experience reduction in those cognitive abilities tested. Researchers did not include anyone younger than the age of 45 but based on these findings believe brain functions could actually begin declining in those younger than 45 years. Researchers believe that conditions negatively affecting cardiovascular function, including obesity, high blood pressure, high cholesterol and smoking are likely associated with these cognitive deteriorations.