Brittle Fingernails

What Causes Brittle Fingernails?

Brittle fingernails can have various causes, ranging in severity from 'minor' to 'life-threatening'.  Finding the true cause means ruling out or confirming each possibility – in other words, diagnosis.

Diagnose your symptoms now!
  • understand what's happening to your body
  • let The Analyst™ find what's wrong
  • identify any nutritional deficiencies

Diagnosis is usually a complex process due to the sheer number of possible causes and related symptoms.  In order to diagnose brittle fingernails, we could:

  • Research the topic
  • Find a doctor with the time
  • Use a diagnostic computer system.
The process is the same, whichever method is used.

Step 1: List all Possible Causes

We begin by identifying the disease conditions which have "brittle fingernails" as a symptom.  Here are eight of many possibilities (more below):
  • Vitamin B3 (Niacin) Need
  • Anorexia/Starvation Tendency
  • Zinc Need
  • Dehydration
  • Nephrotic Syndrome
  • Vitamin A Need
  • Biotin Need
  • Iron Need

Step 2: Build a Symptom Checklist

We then identify all possible symptoms and risk factors of each possible cause, and check the ones that apply:
history of adolescent acne
high diastolic blood pressure
frequent dieting
morning sickness
moderate alcohol consumption
edema of the eyelids
being very easily irritated
vision disturbances
infrequent daytime urination
high Metformin use
history of polyps
reduced skin elasticity
... and more than 90 others

Step 3: Rule Out or Confirm each Possible Cause

A differential diagnosis of your symptoms and risk factors finds the likely cause of brittle fingernails:
Cause Probability Status
Vitamin B3 (Niacin) Need 92% Confirm
Dehydration 22% Unlikely
Vitamin A Need 15% Unlikely
Zinc Need 1% Ruled out
Nephrotic Syndrome 0% Ruled out
Iron Need 0% Ruled out
Anorexia/Starvation Tendency 0% Ruled out
Biotin Need 0% Ruled out
* This is a simple example to illustrate the process

Arriving at a Correct Diagnosis

The Analyst™ is our online diagnosis tool that learns all about you through a straightforward process of multi-level questioning, providing diagnosis at the end.

If you indicate abnormal fingernails and toenails, The Analyst™ will ask further questions including this one:
Are your fingernails brittle - do they chip, peel or break easily?
Possible responses:
→ Don't know
→ No
→ Somewhat
→ Very
Based on your response to this question, which may indicate either absence of brittle fingernails or brittle fingernails, The Analyst™ will consider possibilities such as:

Nails can become brittle due to disease or dehydration.  Nail dehydration can be caused either by external factors such as chemicals, or by the body being dehydrated and trying to conserve water.


Thyroid diseases may produce brittle nails or splitting of the nail bed from the nail plate.

Iron Requirement

A deficiency of essential nutrients and minerals such as iron, zinc, vitamins and calcium can cause the nails to become weak.

Nephrotic Syndrome

Over time, the protein loss occurring in nephrotic syndrome will result in a generally malnourished state, causing hair and nails become brittle.

Concerned or curious about your health?  Try The Analyst™
Symptom Entry
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