Joint Fellowship Training Program
Mentors:
Mona S. Calvo, Ph.D.
Organizational Affiliation and Position:
Expert Regulatory Review Scientist, Nutritionist
Division of Toxicology, Office of Applied Research and Safety Assessment (OARSA), Center for Food Safety and Applied Nutrition (CFSAN), FDA
Email:
mona.calvo@fda.hhs.gov
Telephone:
301-210-7581
Running Title of Program: (Two programs available)
- Edible Mushrooms and Mammary Tumors.
- Vitamin D status and cancer risk: Use of the NHANES survey data to determine nutrient-cancer relationships.
Research Project Summary and Proposed Project for IOTF Fellow:
1. Optimizing vitamin D and ergosterol content of white button and portabella mushrooms (Agaricus bisporus): Effects on innate immune response and mammary tumor development in rodents.
The IOFT Fellow's activity would in part be involved with a proposed study which examines the effects of commonly consumed mushrooms on breast tumor growth and development. Since ancient times many world cultures have prized mushrooms for their exotic taste and medicinal value. Mushrooms are nutritious containing 19-35% high biological quality protein and significant levels of fiber, thiamin, riboflavin, ascorbic acid, vitamin D2 and trace minerals .Mushrooms also contain non-nutritive substances such as ?-glucan, ergosterol, and chitin that have been shown to have anti-tumor, anti-angiogenic and immune response enhancing properties that promote health by preventing chronic diseases such as cancer. Mushrooms are the only natural dietary source of vitamin D2 commonly consumed in the US and Canada and they also contain a high amount of ergosterol or pre-vitamin D2, which when isolated from mushrooms has been shown to have anti-tumor actions. An adequate vitamin D intake is important to the prevention of cancer, infections and other chronic diseases, and this knowledge has been strengthened by several recent cross-sectional or longitudinal studies which demonstrate a significant association between estimates of vitamin D intake and reduction in cancer or other disease risk. Given these findings, vitamin D merits consideration for inclusion in the list of nutrients that could qualify a fruit, vegetable or grain product for a cancer health claim on its label. Moreover, several recent studies have identified a surprisingly high prevalence of vitamin D insufficiency in otherwise healthy adults in North America, which establishes a clear need for more vitamin D rich food sources.
The specific aim of this study is to ascertain if feeding white button mushrooms with optimized vitamin D2 content during early life and through sexual maturity is protective against the development and growth of mammary tumors in a rat model for carcinogen induced mammary cancer. The focus of this study is on the vitamin D2 and ergosterol content of mushrooms and involves exposing the mushrooms to short periods of ultraviolet light (UVB) or sunlight during harvesting to maximize the amount of vitamin D2 and ergosterol content, which is analogous to what happens in human skin upon exposure to sufficient UVB light. Circulating levels of 25(OH)D, the main indicator of vitamin D status, reflect contributions from dietary sources, both natural foods such as fungi (D2) and vitamin D3 from fatty fish and organ meats and vitamin D2 and D3 from fortified foods, and contributions from endogenous synthesis in the skin (D3). In most individuals the largest contributors to circulating 25(0H)D levels is from cutaneous synthesis, however environmental, seasonal, physiologic and behavioral factors are increasingly impairing the amount of vitamin D3 we can make through solar exposure. We have only recently recognized the significant need for more vitamin D rich foods in the US and Canadian food supply in order to maintain adequate serum levels of 25(OH )D to help prevent the development of chronic disease.
2. Use of NHANES survey data to explore the relationship between vitamin D status and intake and the risk of cancer. The IOFT Fellow's activity would also involve participation in an on-going study to examine the association between vitamin D status indicators and dietary intake and the serum levels of specific biomarkers for cancer.
Regulatory Activity:
Fellows would gain both applied epidemiological and test animal experimental experience in gathering the type of data needed by CFSAN regulatory review scientists to make a decision to allow a cancer-nutrient Health Claim on a qualified food or dietary supplement. The findings might indicate a strong relationship that would allow "Vitamin D and Cancer Health Claims" and "excellent or good source" content claim for mushrooms with respect to vitamin D content. The mentor would council the Fellow at all stages of the research both in survey data exploration and in their hands-on involvement in testing the efficacy and safety of mushrooms in preventing tumor growth. The Fellow would also participate in all aspects of regulatory action(s ) that could be initiated with the given results. The applicant for this mentorship has previous experience mentoring medical students in nutrition /endocrine research, over 18 years of experience as a regulatory review scientist, authored the Calcium Osteoporosis Health Claim (one of the original 10 Health Claims for which a review was mandated by Congress), has reviewed several industry submitted health claims, has kept active and current in her field of research and expertise, has participated in the analyses of all calcium and vitamin D related data from the NHANES surveys and is recognized as CFSAN's expert in calcium, phosphorus and vitamin D. Establishing the importance of mushroom consumption to preventing cancer would merit being highlighted by the National Cancer Institutes' Five-A-Day Program that encourages the consumption of fruits and vegetables as a cancer preventive action and such positive findings about mushrooms would allow specific message about the importance of adequate intakes of vitamin D in the 2005 Dietary Guidelines for Americans to specifically draw attention to mushrooms as being a low fat healthy source of vitamin D.
Reference(s):
- Whiting, S.J. and Calvo, M.S. (2005) Dietary recommendations to meet both endocrine and autocrine needs of Vitamin D. Journal of Steroid Biochemistry & Molecular Biology, 97:7-12.
- Calvo, M.S., Whiting, C.N., and Barton, C.N. (2005) Vitamin D intake: a global perspective of current status, Journal of Nutrition, 135:310-316.
- Calvo, M.S., Whiting, S.J and Barton, C.N. (2004) Vitamin D fortification in the US and Canada: current status and data needs. American Journal of Clinical Nutrition, 80:1710S-1716S.
- Calvo, M.S. and Whiting , S.J. (2003) Prevalence of vitamin D insufficiency in Canada and the United States: Importance to health status and efficacy of current fortification and dietary supplement use. Nutrition Reviews, 61:107-113.
- Looker, A.C., Dawson-Hughes, B., Calvo, M.S., Gunter, E.W., Sahyoun, N.R. (2002) Serum 25-hydroxyvitamin D status of adolescents and adults in two seasonal subpopulations from NHANES III. Bone, 30:771-777.
- Brochers, A.T., Keen, C.L. and Gershwin, M.E. (2004) Mushrooms, tumors , and immunity: an update. Experimental Biology and Medicine. 229:393-406.
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