The discrepancy between observational and intervention studies suggests that low 25(OH)D is a marker of ill health .
Inflammatory processes involved in disease occurrence and clinical course would reduce 25(OH)D , which would explain why low vitamin D status is reported in a wide range of disorders .
In elderly people , restoration of vitamin D deficits due to ageing and lifestyle changes induced by ill health could explain why low-dose supplementation leads to slight gains in survival
Low serum concentrations of 25-hydroxyvitamin D ( 25[OH]D ) have been associated with many non-skeletal disorders .
However , whether low 25(OH)D is the cause or result of ill health is not known .
Obesity, mammography use and accuracy, and advanced breast cancer risk.
BACKGROUND Being overweight or obese is associated with increased breast cancer risk and disease severity among postmenopausal women , but whether extent of mammography use and accuracy modify this association and further contribute to increases in disease severity at diagnosis among overweight and obese women is unclear . METHODS We prospect ively collected data during 1996 - 2005 on 287,115 postmenopausal women not using hormone therapy ( HT ) who underwent 614,562 mammography examinations ; 4,446 women were diagnosed with breast cancer within 12 months of a mammography examination . We calculated rates per 1,000 mammography examinations of large ( > 15 mm ) , advanced-stage ( IIb , III , or IV ) , high- grade ( 3 or 4 ) , estrogen receptor (ER)-positive and -negative , and screen-detected and non-screen-detected breast cancer across body mass index ( BMI , kg/m(2 ) ) groups defined as normal ( 18.5 - 24.9 ) , overweight ( 25.0 - 29.9 ) , obese class I ( 30.0 - 34.9 ) , and obese class II/III ( > or = 35.0 ) , adjusting for age , race/ethnicity , and mammography registry and use . All statistical tests were two-sided . RESULTS Adjusted rates per 1000  mammography examinations of overall breast cancer increased across BMI groups ( 6.6 normal , 7.4 overweight , 7.9 obese I , 8.5 obese II/III ; P(trend ) < .001 ) , as did rates of advanced disease , including large invasive ( 2.3 normal , 2.6 overweight , 2.9 obese I , 3.2 obese II/III ; P(trend ) < .001 ) , advanced-stage ( 0.8 normal , 0.9 overweight , 1.3 obese I , 1.5 obese II/III ; P(trend ) < .001 ) , and high nuclear grade ( 1.5 normal , 1.7 overweight , 1.7 obese I , 1.9 obese II/III ; P(trend ) = .10 ) tumors . Rates of ER-positive tumors increased across BMI groups ( P(trend ) < .001 ) ; rates of ER-negative tumors did not . Rates of screen-detected cancers were higher among overweight and obese women than normal and underweight women , but rates of non-screen-detected ( false-negative ) cancers were similar . Rates of advanced breast cancer increased across BMI groups regardless of extent of mammography use . CONCLUSIONS Patterns of mammography use and mammography accuracy are not the primary reasons for higher rates of advanced breast cancer among overweight and obese postmenopausal women not using HT ; thus , biologic differences in breast tumor development and /or progression may be important
The discrepancy between observational and intervention studies suggests that low 25(OH)D is a marker of ill health .
Inflammatory processes involved in disease occurrence and clinical course would reduce 25(OH)D , which would explain why low vitamin D status is reported in a wide range of disorders .
In elderly people , restoration of vitamin D deficits due to ageing and lifestyle changes induced by ill health could explain why low-dose supplementation leads to slight gains in survival
Low serum concentrations of 25-hydroxyvitamin D ( 25[OH]D ) have been associated with many non-skeletal disorders .
However , whether low 25(OH)D is the cause or result of ill health is not known .