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Liver & Bone

Alkaline Phosphatase (ALP)

Alkaline phosphatase is an enzyme present throughout the body but concentrated in liver, bone, intestine, and placenta. Total serum ALP reflects the combined activity of these isoenzymes — most often dominated by the liver and bone forms in adults. It is the second biomarker in the Levine PhenoAge composite, where steadily rising values track biological ageing.

Optimal Ranges

Clinical (NHS) Range

30-130 U/L

U/L

Performance-Optimised Range

40-90 U/L

U/L

The clinical range defines what is considered medically “normal” — broad enough to cover 95% of the population. The performance range reflects where research and clinical experience suggest most people feel and function at their best.

Why It Matters

Why ALP matters for performance

Elevated ALP is the earliest blood signal of cholestatic liver problems (where bile flow is blocked) and is also a sensitive marker of bone turnover — useful in osteopenia, fracture risk, and vitamin D deficiency contexts. Low ALP is less common but can flag zinc or magnesium deficiency, hypothyroidism, or rare metabolic conditions. For longevity scoring, a stable ALP in the lower-middle of the reference range correlates with slower biological ageing.

Symptoms

Signs your levels may be off

Low / Deficiency

  • Often asymptomatic — found incidentally
  • Possible bone aches if from low zinc
  • Fatigue if underlying thyroid issue

High / Excess

  • Itching (from cholestasis)
  • Right-upper-quadrant abdominal discomfort
  • Bone pain (if from bone turnover)
  • Pale stools or dark urine (in obstructive picture)

Dietary Sources

Foods that support ALP levels

ALP itself is endogenous — diet matters via its cofactorsZinc-rich foods: oysters, beef, pumpkin seedsMagnesium-rich foods: leafy greens, dark chocolate, almondsVitamin D from oily fish and sunlightVitamin B6 from poultry, fish, and chickpeas

Supplementation

Evidence-based supplementation

If ALP is suboptimal-low, investigate zinc, magnesium, and B6 status first — these are the enzymatic cofactors. If ALP is rising, the next step is fractionation (bone vs liver) and a vitamin D check, not a supplement. ALP is read alongside GGT (liver) and calcium (bone) to localise the source.

Research

Key study

An epigenetic biomarker of aging for lifespan and healthspan

Levine ME, Lu AT, Quach A, et al.

Aging (Albany NY) (2018)

DOI: 10.18632/aging.101414

Related Biomarkers

Metabolic

ALT (Alanine Aminotransferase)

Optimal: 10-26 U/L

Vitamins & Minerals

Vitamin D (25-OH)

Optimal: 100-150 nmol/L

Vitamins & Minerals

Magnesium (Serum)

Optimal: 0.85-1.0 mmol/L

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ALP is included in the Helvy 50+ biomarker panel. Get your results in 5 days with a personalised protocol.

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This content is for educational purposes only and does not constitute medical advice. Your data suggests areas for optimisation, but any concerns should be discussed with a qualified healthcare professional. If your results flag values outside safe ranges, we recommend consulting your GP.