Fig. 1.

(colour online) Racial/ethnic differences in estimated number of minutes required to synthesize 15 µg (600 IU) of vitamin D from sunlight, in January. Results shown for noontime, assuming no sunscreen and a relationship between average maximum daily temperature and sun exposure (≥23·9°C (≥75°F): face, neck, hands, arms exposed; 15·6–23·8°C (60–74°F): face, neck, hands, lower arms exposed; –1·1 to 15·5°C (30–59°F): face, neck, hands exposed; –9·4 to –1·2°C (15–29°F): face, neck exposed; ≤–9·5°C (≤14°F): face exposed) for: (a) black (darkest skin) minus white (fairest skin); (b) Hispanic minus white (fairest skin)