Parathyroid Hormone (PTH)

Hormones

Vitamin & Mineral Hormones

Parathyroid Hormone (PTH) is the body's main regulator of calcium, mobilizing calcium from bone, increasing its reabsorption in the kidneys, and helping activate vitamin D. It works in close partnership with vitamin D and calcium to keep blood levels tightly controlled. A preventive practice tracks PTH to assess bone health, mineral balance, and the interplay with vitamin D status.

What It Measures

Calcium regulator; mobilizes calcium from bone, increases kidney reabsorption, activates vitamin D

Optimal vs. Lab Range

Longevity Optimal

20–45 pg/mL

Target range for optimal health and longevity based on research.

Standard Lab

15–65 pg/mL

Population-based reference range from standard labs.

Why It Matters

PTH sits at the center of calcium and bone metabolism, so its level reveals how the body is managing these minerals over time. High PTH can reflect primary or secondary hyperparathyroidism, a compensatory rise from vitamin D deficiency, or kidney disease, and sustained elevation can draw calcium from bone, threatening long-term skeletal health. Low PTH may follow parathyroid surgery, accompany magnesium deficiency, or result from vitamin D toxicity. Because PTH responds to vitamin D and mineral status, it is always interpreted alongside calcium, vitamin D, phosphorus, magnesium, and alkaline phosphatase to understand the full mineral and bone picture.

When Low

Hypoparathyroidism (post-surgical), magnesium deficiency, vitamin D toxicity

When High

Hyperparathyroidism (primary or secondary), vitamin D deficiency (compensatory elevation), kidney disease

How to Optimize

Often the most important step is correcting vitamin D deficiency, which can resolve a compensatory PTH elevation, along with maintaining a healthy calcium and magnesium balance. When PTH is elevated without a clear nutritional cause, a physician-directed parathyroid workup is warranted to identify the source. Interpretation always considers the related mineral markers together. Hormone testing and treatment must be individualized with your physician; this content is educational and not a substitute for medical advice.

Key Interventions & Linked Compounds

Strong evidence

Key Interventions

Vitamin D repletion

calcium/magnesium balance

parathyroid workup if elevated

Linked Compounds & Supplements

Vitamin D3

Magnesium

Calcium

Curated from clinical literature. Individual results vary; consult a qualified clinician before changing a protocol.

Ordering Notes

Specimen

Serum; saliva for diurnal cortisol panels

Patient prep

No fasting required. Maintain usual diet and medications unless advised.

Recommended cadence

Annual

Reporting unit

Confirm with the performing lab — units vary by region.

Pre-analytic notes

Standardize draw time of day, hydration, and recent exercise. Note any acute illness, supplements, or hormonal therapies on the requisition.

Recommended Follow-Up Actions

1
Confirm the result is reliable
Repeat abnormal values before acting — preferably from the same lab, same time of day, and under consistent prep. Rule out acute illness, recent intense exercise, or medication effects that can shift Parathyroid Hormone (PTH).
2
Compare against optimal, not just lab range
Use the optimal window above as the target. Lab "normal" is built from the general population and often misses early dysfunction.
3
Pair with related markers
Order a complementary panel covering metabolic, inflammatory, and hormonal context to interpret this marker properly.
4
Discuss interventions with a clinician
Use the interpretation guidance above to frame the conversation. Bring trends, not just one datapoint, to your visit.
5
Re-test on a defined cadence
If a change is implemented, re-measure in 8–12 weeks for fast-moving markers, or 3–6 months for slower ones, to confirm response before escalating.