Research

Hormonal

Late-onset hypogonadism (LOH) defined by sexual symptoms and total testosterone <8 nmol/liter is associated with significant end-organ deficits including lower hemoglobin, bone mineral density, and lean mass, whereas moderate LOH (8-11 nmol/liter) shows only modest tissue-level changes.

If you are an older man experiencing sexual dysfunction (ED, low libido) alongside fatigue or muscle loss, get your testosterone checked. If your levels are below 8 nmol/liter, you likely have Late-Onset Hypogonadism, which is linked to lower bone density, muscle mass, and hemoglobin. However, if your levels are between 8-11 nmol/liter, your metabolic risks are likely due to weight and age, not testosterone, so focus on weight management rather than hormone therapy.

GoodQualifiesHIGH confidence
These data support the existence of a syndrome of LOH in only a minority of aging men, especially those with T below 8 nmol/liter... Both moderate and severe LOH was associated with lower hemoglobin, mid-upper arm circumference, eBMD, and physical function... Only men with severe LOH showed significant associations with larger waist circumference... insulin resistance... and the metabolic syndrome
Abdelouahid Tajar et al. · The Journal of Clinical Endocrinology & Metabolism · 2012

Why this rating

Large cross-sectional population study (n=2966) with rigorous biochemical assays, though causality is limited by cross-sectional design.

Source

Characteristics of Androgen Deficiency in Late-Onset Hypogonadism: Results from the European Male Aging Study (EMAS)

Abdelouahid Tajar et al. · The Journal of Clinical Endocrinology & Metabolism · 2012

DOI 10.1210/jc.2011-2513

cross_sectional · n=2966Cited 310×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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