[0:00]One of my favorite memories as a kiddo was spending time with my granny in Kentucky. Not only did she teach me how to shut corn, she made the best chocolate gravy. Yeah, that's a thing.
[0:15]Hello, it's Natalia from D News. From to grandmother's house we go to grandmother got run over by a reindeer, grandparents are an integral part of holiday celebrations. This is the time of year that extended families make the pilgrimage to their elders. But in a time in a world where most animals begin to mentally deteriorate and die once they reach the end of their reproductive rope, why do humans continue to grow old and become grandparents? A few animals such as dolphins, whales, and humans do have grandparents, which play a key role in caring for their grandkids. And new studies show that there are gene variants that protect against Alzheimer's disease found in some humans that allow them to continue contributing to their families long after they're done producing offspring. Past studies have linked two versions of the gene CD 33 to the development of Alzheimer's disease. However, a variant or allele of CD 33 has been discovered that actually protects against the onset of Alzheimer's disease. This interests scientists because humans, unlike most mammals, continue to live well past our reproductive years. And living past our prime allows humans to contribute to the success of grandkids by handing down knowledge, supplying food, and being cost efficient babysitters while parents tend to other duties or children. This means humans having grandparents gives our species an evolutionary advantage when it comes to having multiple children in shorter intervals. However, those grandparents who do develop dementia or Alzheimer's disease can have the opposite effect on mothers raising multiple children. They become more of a burden. Though there's no proof this gene variant was naturally selected for, it could very well have become selected for randomly. And not everyone has this gene variant, however, learning more about this variant allows for researchers to develop drugs that mimic the variant and help protect patients against the effects of Alzheimer's disease. These findings may support the popular grandmother hypothesis. The grandmother hypothesis was first introduced in 1997 by anthropologist Kristen Hawks after she worked with the Hadza, hunter gatherers in Tanzania. While working with this group of forager, she noticed that grandmothers played an integral part of feeding their grandchildren, allowing mothers to tend to her other children. This assistance over time has allowed women to have more children and shorter intervals, increasing her fecundity. In a 2012 study by Hawks has been able to further support the grandmother hypothesis through computer simulations that prove that a little grandmother over time can increase a species' lifespan by years. However, grandkids aren't the only ones benefiting from having Bubby and Pop-Pop around. Studies have shown that grandparents who actually spend time with their grandkids remain mentally alert and physically active longer after they've had their own kiddos. Studies show that postmenopausal grandmas who spend time with their grandkids have a decreased chance of developing Alzheimer's disease or other cognitive disorders. But the study also showed that grandmothers who spent too much time with their grandkids had greater cognitive impairments and felt their children were too demanding with their child care needs. So, somewhere in between there's a happy medium of grandkid grandparent interaction. Something to consider is that nowadays grandkids don't always live in close proximity with their grandparents, so both the grandkids and the grandparents potentially miss out on the benefits of interacting with one another. A study released by the National Academy of the Sciences show that older men and women who spent long periods away from their family had a 26% higher risk of death in a seven-year period than those individuals who were more engaged with their loved ones. Thus, by spending more time with your grandparents, you may be extending their life. How's that for pressure? Grandparents are definitely grand and unique, so be sure to give yours an extra hug this holiday season. And if they've departed, raise a glass to them and thank them for their contribution to your survival. And for more information about the benefits of having an older population in our midst, check out this video. They found older populations can cause increased productivity and are usually more financially stable, which is good for the economy. Plus, those pop-pops and nanas are able to share that wealth with their children as they age. So what do you think? Do you feel the quality time with your Nana benefited you both? Tell us in the comments below and be sure to subscribe for videos every day of the week.
