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[doug123]

Calcium from food better than pills
Women's Health News
Published: Wednesday, 27-Jun-2007 

The majority of women today are aware that calcium is essential in preventing osteoporosis, especially after the menopause.

Osteoporosis is a disease which causes progressive bone loss and fractures and it affects millions of Americans.

A preliminary study has found that when it comes to maintaining strong bones after the menopause, women may be better off eating plenty of calcium-rich food rather than relying on supplements for their intake of the mineral.

The researchers at Washington University School of Medicine say though their study is not definitive, dietary calcium may be better at protecting bone health than calcium which comes mainly from tablets.

They say this proved to be true even though the supplement-takers had higher average levels of calcium.

The study's lead author, Dr. Reina Armamento-Villareal says calcium from dietary sources is generally better absorbed than that from supplements, which could help explain the difference.

Dr. Armamento-Villareal, a bone specialist and assistant professor in the School of Medicine's division of bone and mineral diseases, says those getting calcium from foods also had more estrogen in their bodies which is needed to maintain bone mineral density.

As yet the food-estrogen connection remains unclear but the research says Armamento-Villareal is preliminary and offers a hypothesis to test.

For the research 183 postmenopausal women were asked to carefully log their diet and their calcium supplement intake for seven days; their bone mineral density and their urine for levels of estrogen were then tested.

The women were then split into three groups: those who got at least 70 percent of their daily calcium from supplements, those who got the same amount from dairy products and other food, and those whose calcium-source percentages fell somewhere in between.

It was found that although the "diet group" took in the least calcium, an average of 830 milligrams per day they had higher bone density in their spines and hip bones than women in the "supplement group", who consumed 1,030 milligrams per day.

Women in the "diet plus supplement group" tended to have the highest bone mineral density as well as the highest calcium intake at 1,620 milligrams per day.

An analysis showed that women in the "diet group" and the "diet plus supplement group" had higher levels of estrogen, needed for bone mineral density.

Other experts agree that the study is not definitive and suggest that those who got calcium from their diet might have also taken in more vitamin D from milk, which would aid in calcium absorption.

They say the estrogen connection might be explained by the possibility that plants were eaten which contain more of the hormone.

Dairy foods and calcium-fortified orange juice are excellent sources of calcium along with dark green, leafy vegetables but it is not as readily absorbed as calcium from dairy.

The study is published in the American Journal of Clinical Nutrition.

First, for my fellow laymen and women, may I please present some introductory information regarding the American Society for Nutrition (this is the primary source from which the news story above is reporting) - ASN (publishers of The American Journal of Clinical Nutrition)? This is public information regarding ASN (and presumably its publications) provided by the U.S. Department of Health and Human Services:

American Society for Nutrition - ASN

Organization URL(s)

sec@nutrition.org
www.nutrition.org

Other Contact Information

9650 Rockville Pike, Suite L-4500
Bethesda, MD 20814

301-634-7050 (Voice)
301-634-7892 (FAX)

Description

The American Society for Nutrition (3,500, members) is the premier research society dedicated to improving the quality of life through the science of nutrition. The Society fulfills its mission via the following: fostering and enhancing research in animal and human nutrition; providing opportunities for sharing, disseminating, and archiving peer-reviewed nutrition research results (at its annual meeting and in its official publications, The Journal of Nutrition and the American Journal of Clinical Nutrition); fostering quality education and training in nutrition; upholding standards for ethical behavior in research, the protection of human subjects, and the care and treatment of research animals; providing opportunities for fellowship and support among nutritionists; and bringing scientific knowledge to bear on nutrition issues through communication and influence in the public domain.
Print Resources

The American Society for Nutrition publishes "The American Journal of Clinical Nutrition" and "The Journal of Nutrition."

The study abstract:

American Journal of Clinical Nutrition, Vol. 85, No. 5, 1428-1433, May 2007
© 2007 American Society for Nutrition

ORIGINAL RESEARCH COMMUNICATION

Effects of dietary calcium compared with calcium supplements on estrogen metabolism and bone mineral density1,2,3,4
Nicola Napoli, Jennifer Thompson, Roberto Civitelli and Reina C Armamento-Villareal
1 From the Division of Bone and Mineral Diseases, Washington University School of Medicine, St Louis, MO

Background: High calcium intake has been associated with both high bone mineral density (BMD) and high urinary estrogen metabolites. However, the role of dietary calcium and calcium supplements on estrogen metabolism and BMD remains unknown.

Objective: The objective was to investigate the importance of the source of calcium intake on estrogen metabolism and BMD.

Design: The average total daily calcium intake from supplements and diet, urinary estrogen metabolites, and spine and proximal femur BMD were studied in 168 healthy postmenopausal white women.

Results: Women who obtained calcium primarily from the diet or from both the diet and supplements had significantly (P = 0.03) lower ratios of nonestrogenic to estrogenic metabolites (2-hydroxyestrone 1/16-hydroxyestrone) than did those who obtained calcium primarily from supplements. Adjusted BMD z scores were significantly greater in the subjects who obtained calcium primarily from the diet or from both the diet and supplements than in those who obtained calcium primarily from calcium supplements at the spine (P = 0.012), femoral neck (P = 0.02), total femur (P = 0.003), and intertrochanter (P = 0.005). This difference was evident especially in those who obtained calcium primarily from the diet, whose total calcium intake was lower than that in those who obtained calcium primarily from supplements.

Conclusion: Calcium from dietary sources is associated with a shift in estrogen metabolism toward the active 16-hydroxyl metabolic pathway and with greater BMD and thus may produce more favorable effects in bone health in postmenopausal women than will calcium from supplements.

Key Words: Calcium • estrogen metabolism • bone mineral density • osteoporosis

Take care.

[krillin]

More precisely, calcium from food is better than pills for maintaining bone density. It's worse for cancer.


Carcinogenesis. 2003 May;24(5):991-1005.
Predictors of the plasma ratio of 2-hydroxyestrone to 16alpha-hydroxyestrone among pre-menopausal, nulliparous women from four ethnic groups.
Jernström H, Klug TL, Sepkovic DW, Bradlow HL, Narod SA.
The Jubileum Institute, Department of Oncology, Lund University Hospital, Sweden.

Studies of circulating estrogen levels in relation to pre-menopausal breast cancer risk have yielded inconsistent results. Various estrogen metabolites might affect the risk differently. Estradiol metabolism occurs primarily via two mutually exclusive pathways, yielding 2-hydroxyestrone (2-OHE) and 16alpha-hydroxyestrone (16alpha-OHE). Most, but not all, studies have found that a relatively high 2-OHE/16alpha-OHE ratio is associated with a low breast cancer risk. Our objective was to determine if the 2-OHE/16alpha-OHE ratio in plasma correlates with suspected breast cancer risk factors and other lifestyle factors, such as ethnicity, body size, age at menarche, oral contraceptive use, smoking, vegetarian diet, coffee and alcohol consumption in 513 nulliparous women, aged 17-35. Oral contraceptive users had significantly lower 2-OHE/16alpha-OHE ratios than pill non-users (P = 10(-21)). Among women who were not using oral contraceptives, the median 2-OHE/16alpha-OHE ratio in plasma was similar for white, black, Indian/Pakistani and Asian women, after adjustment for age and menstrual cycle phase. Among oral contraceptive users, Asian women had significantly lower 2-OHE/16alpha-OHE ratios than white women, and this result remained after adjustment for age and day of menstrual cycle. Daily coffee consumption was significantly positively correlated with 2-OHE/16alpha-OHE ratios (r(s) = 0.18, P = 0.002) only among pill non-users. Our findings suggest that the plasma 2-OHE/16alpha-OHE ratio is associated with constitutional factors and with modifiable lifestyle factors. The reported elevated risk of early onset breast cancer among young oral contraceptive users could be mediated in part through altered estrogen metabolism induced by synthetic estrogens and progestins.

PMID: 12771045

Altern Med Rev. 2002 Apr;7(2):112-29.
Estrogen metabolism and the diet-cancer connection: rationale for assessing the ratio of urinary hydroxylated estrogen metabolites.
Lord RS, Bongiovanni B, Bralley JA.
MetaMetrix Clinical Laboratory, 4855 Peachtree Industrial Boulevard, Suite 201, Norcross, GA, 30092, USA. rslord@metametrix.com

Estrogens are known for their proliferative effects on estrogen-sensitive tissues resulting in tumorigenesis. Results of experiments in multiple laboratories over the last 20 years have shown that a large part of the cancer-inducing effect of estrogen involves the formation of agonistic metabolites of estrogen, especially 16-alpha-hydroxyestrone. Other metabolites, such as 2-hydroxyestrone and 2-hydroxyestradiol, offer protection against the estrogen-agonist effects of 16-alpha-hydroxyestrone. An ELISA method for measuring 2- and 16-alpha-hydroxylated estrogen (OHE) metabolites in urine is available and the ratio of urinary 2-OHE/16-alpha-OHE (2/16-alpha ratio) is a useful biomarker for estrogen-related cancer risk. The CYP1A1 enzyme that catalyzes 2-hydroxyestrone (2-OHE1) formation is inducible by dietary modification and supplementation with the active components of cruciferous vegetables, indole-3-carbinol (I-3-C), or diindolylmethane (DIM). Other dietary components, especially omega-3 polyunsaturated fatty acids and lignans in foods like flax seed, also exert favorable effects on estrogen metabolism. Thus, there appear to be effective dietary means for reducing cancer risk by improving estrogen metabolism. This review presents the accumulated evidence to help clinicians evaluate the merit of using tests that measure estrogen metabolites and using interventions to modify estrogen metabolism.

PMID: 11991791