IGF-1 — lab reference
Age, sex, nutrition, liver disease, diabetes, and assay matter.
THE PURSER WELLNESS ENCYCLOPEDIA
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A RELATED COURSEThe thyroid conversation
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New to this subject? Start with this free introduction.Thyroid Problems and Solutions with Dan Purser MD - Part 1
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What’s searchable?Growth hormone, random — lab reference
Pulsatile secretion makes random GH difficult to interpret; stimulation/suppression testing may be needed.
Parathyroid hormone (intact PTH) — lab reference
Ask your clinician to read this result with calcium, phosphorus, magnesium, vitamin D, and kidney function.
Aldosterone — lab reference
Sodium intake, posture, potassium, time, medications, and renin method are essential.
Renin / plasma renin activity — lab reference
Direct renin and plasma renin activity are not interchangeable.
Aldosterone-renin ratio — lab reference
Screening cutoff depends on units, method, medications, potassium, and collection protocol.
Plasma free metanephrines — lab reference
How you sit or lie down for the sample, and stress during collection, can affect this result. Use the cutoff from the lab that ran your test.
Program 120: a guide to the preventive-medicine textbook
Explore the subjects in an earlier preventive medicine handbook and follow them into current learning.
Program 120 for women: hormones and lifestyle
Explore questions about hormones, sexual health, food, and daily habits in the women’s handbook.
Program 120 for men: hormones and lifestyle
Explore questions about hormones, sexual health, food, and daily habits in the men’s handbook.
Male sexuality, fertility and testosterone
Learn why libido, erectile function, testosterone, and fertility are different health questions.
Thyroid: cold hands, cold feet and the bigger picture
Learn how symptoms, lab results, and health history fit into a thyroid discussion.
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