Table 1. Age, sex and season-standardized prevalence of plasma vitamin C adequacy status in people aged 60 years and over by location in India.

Plasma vitamin C	Adequate	Sub-optimal	Deficient
	>28 µmol/L	11–28 µmol/L	<11 µmol/L
North India
N = 2668	n = 286	n = 403	n = 1979
Prevalence	10.8	15.3	73.9
95%CI	8.0, 13.5	13.8, 16.8	70.4, 77.5
South India
N = 2970	n = 774	n = 853	n = 1343
Prevalence	25.9	28.4	45.7
95%CI	22.9, 28.9	26.3, 30.6	42.5, 48.9