A person’s sense of smell may help predict their risk for Alzheimer’s disease, a new study suggests.
The researchers included 183 older people, and 10 had possible or probable Alzheimer’s disease, the researchers said.
Study volunteers were tested on their ability to recognize, remember and distinguish between odors. These odors included menthol, clove, leather, strawberry, lilac, pineapple, smoke, soap, grape or lemon. The study participants were then asked to complete another test of odors. The second test included 10 new odors in addition to those from the original test. These tests were developed at Massachusetts General Hospital in Boston.
The participants also underwent genetic, imaging and memory tests. Those with a reduced sense of smell seemed to be at increased risk of Alzheimer’s, the researchers said.
“There is increasing evidence that the neurodegeneration behind Alzheimer’s disease starts at least 10 years before the onset of memory symptoms,” principal investigator Dr. Mark Albers, from the department of neurology at Massachusetts General, said in a hospital news release.
“The development of a digitally enabled, affordable, accessible and noninvasive means to identify healthy individuals who are at risk is a critical step to developing therapies that slow down or halt Alzheimer’s disease progression,” he added.
It’s known that brain circuits that process smells can be affected by Alzheimer’s, and several previous studies have shown that people with the disease have a reduced ability to identify odors, the researchers said.
The Massachusetts General researchers are now recruiting volunteers for a larger study to confirm their findings. “It is well recognized that early diagnosis and intervention are likely to produce the most effective therapeutic strategy for Alzheimer’s disease – preventing on the onset or the progression of symptoms,” Albers said.
The study was published online Nov. 14 in the Annals of Neurology.
Let’s take this study a step further. Zinc deficiency is the most common cause of a loss of sense of smell. Over 38,000 studies have implicated zinc deficiency and/or copper excess as a significant factor in the onset of dementia, Parkinson’s and Alzheimer’s disease.
I suggest a study supplementing these volunteers with zinc and a placebo for the control group.
Zinc is vital to produce HCl (hydrochloric acid) secreted by the stomach as an initial step in digestion. Lack of HCl is known to cause anemia from vitamin B12 deficiency and osteoporosis from a calcium deficiency.
Over 17,000 studies have linked the use of PPIs (proton pump inhibitors) to Parkinson’s disease, dementia and Alzheimer’s disease. Nexium, the most popular PPI was the top selling drug in the US in 2012 and sales of PPIs exceeded 9 billion dollars that year. Despite all the studies, PPIs are listed as generally safe although often abused.
The Bottom Line:
It’s not hard to connect the dots between Alzheimer’s disease, zinc deficiency and long term use of PPIs. If you take a PPI, talk to your doctor about getting off it. If you have lost some of your sense of smell (or taste), consider supplementing zinc.
November 16, 2016 National Institutes of Health