{"doi":"10.1002/ajhb.70118","title":"Biological Benchmarks for Adult Bone Mass Proportions in Young Females: A Prospective Longitudinal Analysis","abstract":"OBJECTIVES: In growing humans, densitometric scans of whole-body bone mass \"less head\" are recommended to circumvent the excessive contribution of youths' proportionally larger heads but potentially inflate inter-scan variation and least significant change due to measurement error. We aimed to determine biological benchmarks for achievement of adult head-body proportions in a sample of US females. METHODS: Annual whole-body dual energy x-ray absorptiometry (DXA) scans tracked growth, maturation, and bone mass accrual in a prospective longitudinal cohort of girls for up to 19 years (baseline age 7-15 years). We used cubic smoothing spline mixed effects models to generate chronological and gynecological age-based curves for head versus whole-body bone mass proportions (ratios). Females with ≥ 3 annual scans were included (n = 148, age 7-30 years). RESULTS: Models yielded trajectories extending beyond observed age at peak bone mass for our sample. From age 18 years, \"adult\" mean of means for head vs. whole-body bone mass proportions was 0.204 (n = 66: 95% confidence interval = 0.198-0.210). Individual proportions stabilized to \"adult\" mean levels circum-menarche (n = 124: mean = 0.198; 95% confidence interval = 0.194-0.202). The minimum age for 95% confidence intervals overlapping with adult values was 12 years, circum-peak height velocity (n = 120: mean = 0.211; 95% confidence interval = 0.207-0.216). CONCLUSION: In US girls with diverse activity exposures, head vs. whole-body bone mass proportions are \"adult\" from menarche onward; an \"adult\" age threshold of 12 years, or age at peak height velocity, may be used in the absence of extreme maturational delay to evaluate whole-body bone mass including the head.","journal":"American Journal of Human Biology","year":2025,"id":553819,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":1,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9193,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2025-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":417891,"name":"Stephanie Kliethermes‌","orcid":"0000-0001-9756-7406","position":1,"is_corresponding":false},{"id":909532,"name":"Tamara A. Scerpella","orcid":"0000-0002-4118-2176","position":2,"is_corresponding":false},{"id":1450739,"name":"Jodi N. Dowthwaite","orcid":"0000-0002-8045-7881","position":0,"is_corresponding":true}],"reference_count":25,"raw_metadata":null,"created_at":"2026-07-19T02:54:45.872391Z","pmid":"40801239","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}