Included in your membership
ALP
All NiaHealth tests are processed in Canadian-certified labs, which are highly trusted by the medical community for their accuracy and reliability. Blood and urine samples are collected by licensed medical professionals and processed using state-of-the-art equipment. NiaHealth is SOC2 Type 2 certified.
What is it?
Alkaline phosphatase, often called ALP, is an enzyme found in several parts of the body. The highest amounts are usually found in the liver, bile ducts, bones, intestines, and placenta. Because ALP comes from more than one body system, a high or low result does not point to one single cause on its own. It needs to be interpreted alongside other blood markers, symptoms, medical history, and sometimes additional testing.
Why it matters
ALP helps give information about liver, bile duct, and bone health.
In the liver and bile ducts, ALP can rise when bile is not flowing normally. This can happen with conditions that affect the bile ducts or gallbladder, such as gallstones or bile duct blockage. ALP can also be elevated with some liver conditions, especially when interpreted alongside other liver markers.
In the bones, ALP is involved in bone turnover and mineralization. This means ALP can rise when bones are actively healing, remodeling, or under stress. Higher ALP may be seen with bone fractures, vitamin D–related bone changes, or other bone conditions.
Low ALP can also be meaningful. Lower levels may be seen with zinc or magnesium deficiency, anemia, malnutrition, hypothyroidism, Wilson's disease, or a rare inherited condition called hypophosphatasia.
Reference ranges
A result within the reference range usually suggests that ALP is not clearly elevated or reduced. However, ALP is still best interpreted in context, especially if it is near the high or low end of the range or changing over time.
A high ALP may be related to the liver, bile ducts, gallbladder, bones, or intestines. Reviewing ALP alongside GGT, ALT, AST, bilirubin, calcium, phosphate, vitamin D, or parathyroid hormone, can help determine where the ALP is coming from.
A low ALP may point toward nutritional, thyroid, blood-related, or genetic causes. It gives the best information when it is interpreted alongside other health information rather than reviewed by itself.
Some research shows that, even within the reference range, higher ALP levels are linked with higher long-term health risk. This does not mean ALP itself should be "lowered" as a treatment target. Instead, ALP can act as a signal to look more closely at liver, gallbladder, bone, metabolic, and cardiovascular health.
If ALP is clearly high, clearly low, or changing over time, additional testing may help identify the cause and guide next steps.
Makris, K., Mousa, C., & Cavalier, E. (2023). Alkaline phosphatases: Biochemistry, functions, and measurement. Calcified Tissue International, 112(2), 233–242.
Minisola, S., Cipriani, C., Colangelo, L., Labbadia, G., Pepe, J., & Magnusson, P. (2025). Diagnostic approach to abnormal alkaline phosphatase value. Mayo Clinic Proceedings, 100(4), 712–728.
Yan, W., Yan, M., Wang, H., & Xu, Z. (2023). Associations of serum alkaline phosphatase level with all-cause and cardiovascular mortality in the general population. Frontiers in Endocrinology, 14, 1217369.
This information is educational and does not replace medical advice, diagnosis, or treatment. Your results should be interpreted with a qualified healthcare professional in the context of your health history.
