A study found that slow walking speed is associated with cognitive decline in older people. They discovered the volume of these old patient's right hippocampus, an area of the brain that plays a huge role in both memory and spatial orientation, shrinks. A decrease in volume means there are brain cells dying. And a lot of studies showed that people who are active in physical activities have greater brain volume.

But walking faster is not a cure but rather reduces the chance of gaining memory loss and improves the brain's resistance to Alzheimer's disease, an irreversible progressive brain disorder that slowly destroys memory and thinking skills and affects the quality of life especially in old people.

And if one of your grandparents is walking slooooooowly, refer them to a specialist for diagnostic testing. The early the treatment, the better. Specialists might recommend them to undergo physical therapy to avoid cognitive impairment. If treated early, there would be less chance of your beloved grandparents getting dementia.