Serum vitamin D concentrations are related to depression in young adult US population: the Third National Health and Nutrition Examination Survey

Table 1 Characteristics of study population: the Third National Health and Nutrition Examination Survey¹

Characteristic	Value
Women	54.2
Non-Hispanic white	28.6
Non-Hispanic black	33.0
Live in South and West regions	70.4
Live in urban areas	51.9
Supplement use ²	28.4
Prescription medicine use ³	23.1
Persons living below poverty ⁴	27.2
Persons with overweight and obesity ⁵	47.2
Persons had a major depression	7.9
Persons had depression episodes longer >2 y	11.9
Persons having depression currently ⁶	4.0
Age (y)	27.5 ± 0.2
Poverty income ratio ⁷	2.74 ± 0.1
Body mass index (kg/m²)	25.3 ± 0.1

¹ n = 7970. Values are % or means ± standard error of mean
² Vitamin/mineral supplement use 1 month prior to the survey
³ Prescription medicine use 1 month prior to the survey
⁴ Poverty was defined as having poverty income ratio <1.0. Poverty income ratio is the ratio of a family's income to their appropriate threshold income.
⁵ Overweight and obesity were defined as having BMI 25 to <30 kg/m² and ≥30 kg/m², respectively
⁶ Based on the question "Are you in one of these spells of feeling low or disinterested and having some of these other problems now"?
⁷ The ratio of a family's income to their appropriate threshold income