Do these Covid symptoms reveal Parkinson’s risk?

Dr. Frank Shallenberger, MD

March 1, 2021

Here’s a quiz: Which is more likely to determine your risk of Parkinson’s disease: a family history or two specific Covid-19 symptoms?

The answer might surprise you.

Every month, I see patients who have a family history of Parkinson’s. Every one of them is very concerned about getting the disease. And they’re willing to do just about anything to make sure they don’t get it themselves.

But the fact is that 85% of the time someone gets Parkinson’s there is no family history.

So for the most part, we are all at equal risk no matter what your genetics are. While genetics may not be the problem, a new study suggests that two common symptoms of Covid-19 are a more accurate predictor of who will get Parkinson’s.

Parkinson’s occurs with the destruction of certain nerve cells in a part of the brain called the substantia nigra. The cause of this destruction? An excessive amount of free radicals in the substantia nigra.

To counter this, the substantia nigra has high levels of the enzyme SOD (superoxide dismutase). SOD removes free radicals and prevents them from damaging cells.

And there’s one mineral that is a critical component of this enzyme – zinc. In the absence of enough zinc, the enzyme will not work and Parkinson’s can develop.

So the authors of this study wanted to look at how a deficiency of zinc may play a role in Parkinson’s.

Here’s What They Did

The researchers took 100 patients with Parkinson’s and 25 people without the disease and measured their zinc status. They used two different ways to measure zinc deficiency.

One way was through symptoms. People with a deficiency of zinc often complain of decreased vision, a decreased sense of smell, and a decreased sense of taste. As you may know, two of the common symptoms of Covid-19 are a loss of smell and taste. This is connected to zinc.

The researchers found that the patients with Parkinson’s were 51% more likely to have a history of decreased vision, 56% more likely to have a history of decreased smell, and 33% more likely to have a decreased sense of taste.

The researchers also used a functional test for zinc called the zinc tally test. Parkinson’s patients were significantly more likely to have a deficiency of zinc based on this test than the healthy people were.

I use a different kind of test to evaluate the zinc status of my patients. I use the Functional Intracellular Analysis from the laboratory Spectracell. It is similar to the zinc tally test these authors used in that it’s what we call a “functional” test. A functional test is one that takes into account the patient’s genetic makeup.

A functional test is different from simply looking at a blood level of zinc. A blood level will tell you only how high your level of zinc is compared to the general population.

But blood levels of nutrients are for the most part useless information. That’s because even though your level may be in the normal range, it in no way is proof that this level is high enough for your genetic needs.

And here’s the point. The single most common deficiency I see using this test is zinc deficiency. So I know it is very common.

What to Do

So if you have Parkinson’s or if you are concerned about getting it, I suggest you have your zinc status checked out. This would be especially true if you have noticed a decrease in your vision, smell, or taste.

If you’ve had Covid-19 and you lost your sense of taste or smell, it’s likely you’re deficient. Make sure you correct your deficiency before you develop an even worse disease.

When you get your zinc status checked, ask your doctor how much zinc you need to take to correct the deficiency. A maintenance dose is only 15 mg daily. But you might need a lot more than that to correct your status.


Forsleff, L., A.G. Schauss, I.D. Bier, and S. Stuart. “Evidence of functional zinc deficiency in Parkinson’s disease.” J Altern Complement Med. 1999 February;5(1):57-64.

Ready To Upgrade?

Upgrade now to a Second Opinion Newsletter Subscription so you don't miss out on the healthy, active life you deserve.

Plus, Get Up To 18 Free Reports When You Click Here To Upgrade Today!

Get A Free Copy Of This Powerful Report

Inside You'll Discover

► A little secret that not only relieves stress but can actually banish stress from your life!

► If you are exercising too hard to be healthy.

► And, an optimal exercise regimen to excerise smarter, not harder!

Enter your name and email to claim this free report and join our newsletter

Get Report!