The Recommended Dietary Allowance (RDA) for Vitamin D is currently set at 600–800 IU/day (15–20 mcg) for adults. Fortified milk typically provides 100 IU per 8 oz serving (236 mL). So while milk can provide a good amount of vitamin D it may not be sufficient to ensure adequate daily intakes.
In fact, adults who rely on food sources alone for vitamin D may only be getting half their daily vitamin D requirement on average. Those who take a vitamin D supplement are much more likely to achieve the RDA.
Doses higher than the RDA may be warranted in cases of deficiency, non-response at lower dosages, or in those with a BMI >30. In these cases, a 1,000–2,000 IU/day (25–50 mcg) dose (or greater) of vitamin D may be necessary.
So, unless you are drinking 6+ glasses of milk a day, consuming other vitamin D rich foods (fatty fish, egg yolks) or considering supplementation will be required.
- . Dietary Reference Intakes for Calcium and Vitamin D . . ()
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