How your fingernails reveal a zinc deficiency

We’ve seen over recent posts that fingernails are great little indicators of general health and nutritional status.

Both biotin and vitamin B1 (thiamine) deficiency can be indicated by nail quality.

Brittle, cracking nails along with damaged cuticles may indicate biotin deficiency, while horizontal nail lines and ridges indicate B1 deficiency.

These nutrient deficiencies can be far reaching, leaving you feeling tired, stressed and grumpy, while causing balance, concentration, skin and hair problems, and even issues with your genetic expression.

Here’s another way you can assess your nails to see if your nutrient levels are optimal.

White fingernail specks and zinc deficiency

A zinc deficiency will create these little white specks on the nail, as in the picture below.

Because your nails grow completely every six months or so, you can see specifically when the zinc deficiency kicked in.

In the photo, for example, the zinc deficiency would have occurred in this person approximately 1.5 to 2 months earlier.

The white speck will continue to move towards the end of the fingernail and eventually grow out.

How important is zinc?

While all 300 or so human nutrients are important, zinc is near the top of the hierarchy.

  • It runs dozens of enzyme pathways to help your metabolism run smoothly.
  • It is essential for optimal hormone and neurotransmitter production and metabolism.
  • Zinc is critically important for reproduction.
  • Zinc is required for optimum immune function – your immune system simply cannot function without zinc, which not only damages your ability to resist infections, but also hinders growth and repair
  • Zinc stabilizes your DNA.

Bottom line: you cannot feel good if you are deficient in zinc and you’ll probably get your fair share of colds and flu when others around you don’t.

If you have a chronic zinc deficiency, the research shows that you may be more prone to developing problems such as:

  • Digestive disorders, especially diarrhea
  • Depression
  • Respiratory tract infections
  • Pneumonia
  • Heart attacks
  • Diabetes
  • Thyroid problems
  • Alzheimer’s disease

To quote a scientific paper from 2014:

“Organ systems that are known as being clinically affected by severe zinc deficiency include the central nervous, gastrointestinal, immune, epidermal, reproductive, and skeletal systems.

I’m sure you’ll agree that optimizing your zinc level is important.

Why does zinc deficiency happen?

Zinc is used up quickly when you’re under stress or when you have an infection (in actual fact, an infection is a type of stress).

If you have a chronic infection with something like H. pylori, Candida or parasites like Giardia in your digestive system, which is something we see in the practice every day, it’s highly likely that your zinc levels will be adversely affected.

So stress and infections are two ways your zinc level can be depleted.

In addition, not eating enough zinc in your diet will cause problems. Diets high in processed food predispose to zinc deficieny (and many other nutritional imbalances).

Even if you eat plenty of zinc, you might not absorb it properly if your digestive system is compromised.

As always, we have to go back to the digestive system and make sure it is working properly.

Low stomach acid affects zinc absorption, and we know that low stomach acid can be caused by H. pylori infections, for example

Furthermore, inflamed intestines due to Candida, parasites and food sensitivities to things like gluten can also sabotage zinc absorption.

For example, a 2010 paper on the intestinal parasite Giardia, states:

“Giardia infection was associated with vitamin A and zinc deficiency and further impairment in nutrition.”

Another paper, this time from 2017, states:

“The association between zinc malabsorption and giardiasis has been established; however, the mechanism responsible remains unclear.”

This is why we always need to go back to your diet and gut health when it comes to uncovering the reasons for nutrient deficiencies.

Lab test indicators for zinc deficiency

Zinc deficiency is relatively easy to test. Well I say that, but it really depends on how your doctor interprets your blood test!

Blood tests

Most standard blood test labs have a marker called alkaline phosphatase (ALP).

Doctors generally only flag ALP as a problem when it’s too high. High levels can indicate liver problems, bone loss, viral infections or leaky gut.

However, when it’s too low, ALP indicates zinc deficiency (unfortunately doctors are not trained to flag this).

In addition to checking for low ALP, you can directly measure your plasma zinc level. This test is not usually included in standard blood tests.

When working with clients, we order plasma zinc from the lab as an add-on marker.

We also check the ratio of zinc to copper, as this is very important. These nutrients work as a pair and aberrant copper levels can cause zinc imbalances (copper is highly toxic when it is too high).

Hair mineral analysis

Hair testing can be really useful because they’re inexpensive and can easily be done at home. As with blood testing, however, a hair test needs skillful interpretation.

Either low or high zinc levels in a hair test can indicate zinc deficiency. A high level indicates that zinc is being dumped or lost by the body, usually because of some kind of stress.

A good hair test also provides information about the zinc to copper ratio, which has been one of the most important considerations for some of our clients.

Where do you start?

I realise all this information can be a little confusing, so let’s simplify.

First, check your nails – do they have white spots, or have you ever noticed white spots?

Do your nails peel and crack easily? Are they brittle, or do they have ridges?

If the answer is “yes”, then something is going on.

Look at your diet. Clean it up.

Eat less processed food and more whole, unprocessed natural food (organic if possible, as you will get more nutrients into your body this way).

Regarding lab testing, it’s going to depend on your individual situation.

If you experience digestive symptoms such as heartburn, acid reflux, bloating, constipation, loose stools, gas, etc. then a stool test is the best starting point.


Because until you have healthy digestion, you will not optimise your nutrient levels, including zinc.

If your digestion feels pretty good, then having someone interpret your blood work in detail (more detail than just a medical interpretation) is a great starting point.

If you’re not feeling well, do something, because doing nothing isn’t going to resolve a damned thing and the solution could be really simple.

You could be feeling crappy just because you have one or two simple nutrients missing or depleted.

Our job is to help you get better, sooner, so if you’d like some assistance to cut through the noise and confusion, consider one of the options below.

Click here if you’d like more about getting stool test done, or to order one.

Click here if you’d prefer to schedule a 60min consultation where we can review your case and help you plot a course of action.

Whatever you do, don’t do nothing, and remember that the path to optimal health may be simpler than you think.

All my best,