Effect of Consumption of Post-harvest UV-B Treated Mushrooms on Vitamin D Status of Healthy Adults

Volunteers will be asked to consume a standard meal (lunch) containing one serving of mushrooms daily for six weeks (7 days per week). With the meal, they will also need to take one capsule. The capsule will be either a placebo or will contain vitamin D. The purpose of the vitamin D in the capsule is to determine if the vitamin D from the mushrooms is absorbed as well as vitamin D from a capsule. The total dose of vitamin D that volunteers will receive each day from mushrooms and capsule together will always be the same and will be one of three doses: (1) little or no vitamin D (placebo); (2) 400 IU, which is near the current recommended intake and (3) 1,000 IU, which is up to five-fold higher than the current recommended intake, depending on your age. Both levels of vitamin D are safe. In addition to consuming the meals and taking the capsules, up to 20 mL (4 teaspoons) of blood will be drawn at three times during the study just before the mushroom-containing lunch is provided: (1) at the beginning of the study before the first meal; (3) after three weeks; (3) at the end of the study. The purpose of the blood draw is to measure vitamin D in your blood and to measure the level of activation of your immune system by measuring markers of immune activation.