Quick answer: Parathyroid hormone (PTH) is made by four small glands in the neck and keeps blood calcium in a tight range by acting on bones, kidneys and vitamin D. PTH is always interpreted with calcium and vitamin D. High PTH with high calcium suggests hyperparathyroidism; high PTH with low vitamin D is common and affects bone health.
What is PTH?
PTH is released by the parathyroid glands when blood calcium falls. It pulls calcium from bone, reduces calcium loss in urine and activates vitamin D to absorb more calcium from food. This marker is part of the Healthspan Assessment panel available to my 1-on-1 patients.
Why PTH matters
- Calcium balance
- Bone remodeling
- Vitamin D activation
- Nerve and muscle function
Understanding your result
Reference ranges vary by lab, age and sex. Your provider interprets your result against the lab’s range and your overall picture, rather than chasing a single number. Functional labs are optional. They can be helpful in more complex cases, and in my practice they are available only to patients working 1-on-1 with me.
What low PTH can mean
- Damage or removal of the parathyroid glands (for example, after neck surgery)
- Low magnesium
- High calcium from other causes
What high PTH can mean
- Primary hyperparathyroidism (often with high calcium)
- Low vitamin D or low calcium intake (secondary)
- Kidney disease
What affects PTH
- Vitamin D status
- Calcium intake
- Magnesium
- Kidney function
Ways to support healthy levels
- Check and correct vitamin D (see vitamin D test)
- Get calcium from food such as dairy, sardines and leafy greens
- Support bones with strength training (see osteoporosis prevention)
- High calcium with high PTH needs a medical evaluation
PTH and healthy aging
Persistently high PTH slowly pulls calcium from bone, contributing to bone loss with age. Balanced PTH, calcium and vitamin D support healthy bone renewal.
When to see a naturopathic doctor
- Abnormal calcium results
- Low vitamin D
- Osteoporosis or fractures
- Kidney stones
See a medical provider promptly for confusion, severe weakness, muscle spasms, tingling around the mouth or extreme thirst.
Want help making sense of your labs?
A free 15-minute consultation with Dr. Kneessi. No cost, no obligation. In-office in Odenton, MD or by telehealth.
Frequently asked questions
Why test PTH with calcium?
PTH only makes sense when read alongside calcium and vitamin D.
What does high PTH mean?
It can mean hyperparathyroidism or a response to low vitamin D or calcium.
Can vitamin D affect PTH?
Yes. Low vitamin D often raises PTH.
Does PTH affect bones?
Yes. Long-term high PTH can weaken bones.
Sources
This article is for educational purposes only and is not medical advice. It does not replace an individual evaluation. Talk with your healthcare provider before starting supplements or changing medications, especially if you are pregnant, nursing, or managing a health condition.
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