Dean Pomerleau Posted April 1, 2016 Report Share Posted April 1, 2016 All, In today's video (embedded below), Dr. Greger highlights an ex vivo study [1] of almond consumption and bone health, which I thought was pretty cool and promising, despite it being sponsored by the Almond Board of California. Ex vivo you say? I've heard of in vivo and in vitro, but what is ex vivo? It's when you treat a subject, in this case by feeding them a handful of almonds, wait a few hours, and then draw some of their blood in order to drip it on something outside the body (e.g. cancer cells) to see how the cells reacts (hence ex vivo - latin for "outside the living"). In this case they took the blood of almond-consuming subjects and dripped it on osteoclast cells, the cells in our bones whose job it is to break down bone cells, and whose activity is an important contributor to osteoporosis. They found osteoclast proliferation and activity was markedly reduced (a good thing) by the blood of the almond consumers relative to the blood of controls, suggesting almonds should have a positive effect on maintaining bone health by reducing bone tissue breakdown. This jibes with at least one population study [2], which found almonds to be one of foods associated with reduced osteoporosis. As we all know, the problems with population studies are many, including relying of dubious food frequency questionnaires, and being confounded by many lifestyle differences between the participants that could have been responsible for the observed effect (reduced osteoporosis), rather than the almonds. The sort of ex vivo experiment done in [1] gets the best of both worlds. It has the advantage of studying real people eating and importantly, digesting and assimilating known reasonable quantities of real whole foods, rather than just dripping purified almond extracts directly onto osteoclasts in a petri dish. But at the same time it allows researchers to look at the details of the mechanisms involved, without invasive procedures, which in this case would have entailed a dangerous and painful bone marrow biopsy, which no IRB would allow in a human study. Anyway, pretty cool, and seemingly reasonable evidence that almonds (and probably other nuts) may be beneficial for preventing bone loss. --Dean --------- [1] Metabolism. 2011 Jul;60(7):923-9. doi: 10.1016/j.metabol.2010.08.012. Epub 2010 Oct 13. Postprandial effects of almond consumption on human osteoclast precursors--an ex vivo study. Platt ID(1), Josse AR, Kendall CW, Jenkins DJ, El-Sohemy A. Author information: (1)Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada. Consumption of almonds has been associated with increased bone mineral density, but the direct effects of almonds on bone cells are not known. We determined whether serum obtained following the consumption of a meal containing 60 g of almonds affects human osteoclast formation, function, and gene expression in vitro. Human osteoclast precursors were cultured in medium containing 10% serum obtained from 14 healthy subjects at baseline and 4 hours following the consumption of 3 test meals containing almonds, potatoes, and rice and balanced for macronutrient composition. Osteoclast formation was determined by the number of tartrate-resistant acid phosphatase (TRAP)(+) multinucleated cells, and osteoclast function was assessed by measuring TRAP activity in the culture medium and calcium released from OsteoAssay (Lonza Walkersville, Walkersville, MD, USA) plates. The expression of cathepsin K, receptor activator of nuclear factor kB, and matrix metalloproteinase-9 genes was measured by real-time reverse transcriptase-polymerase chain reaction. Compared with serum obtained at baseline, serum obtained 4 hours following the consumption of the almond meal reduced osteoclast formation by approximately 20%, TRAP activity by approximately 15%, calcium release by approximately 65%, and the expression of cathepsin K, receptor activator of nuclear factor kB, and matrix metalloproteinase-9 by 13% to 23%. No effects were observed with serum obtained from the other test meals. Serum obtained 4 hours following the consumption of an almond meal inhibits osteoclast formation, function, and gene expression in cultured human osteoclast precursors, and provides evidence for a positive effect of almonds on bone health. Copyright © 2011 Elsevier Inc. All rights reserved. PMID: 20947104 ------------- [2] BMC Musculoskelet Disord. 2008 Feb 27;9:28. doi: 10.1186/1471-2474-9-28. The assessment of osteoporosis risk factors in Iranian women compared with Indian women. Keramat A(1), Patwardhan B, Larijani B, Chopra A, Mithal A, Chakravarty D, Adibi H, Khosravi A. Author information: (1)Shahroud University of Medical Sciences, Hafte Tir Avenue, Shahroud, Iran. keramat1@yahoo.com BACKGROUND: Osteoporosis is an important public health problem in older adults. It is more common in postmenopausal women and not only gives rise to morbidity but also markedly diminishes the quality of life in this population. There is lack of information about the risk factor of osteoporosis in developing countries. In this study we aimed to assess the risk factors for osteoporosis in postmenopausal women from selected BMD centers of two developing Asian countries (Iran and India). METHODS: This study is a multicenter interview-based study conducted in selected hospitals and health centers from urban areas in Iran and India. The case group included postmenopausal osteoporotic women who were identified as patients with bone density higher than 2.5 SD below average of young normal bone density (in L1-L4) spine region interest and/or total femoral region) by using DEXA method. The controls were chosen from postmenopausal women with normal bone density (in L1-L4 spine and total femoral regions using DEXA method) matching in age groups was strategy of choice.The sample sizes included from Iran a total of 363 subjects (178 osteoporotic and 185 normal) and from India a total of 354 subjects (203 osteoporotic and 151 normal). RESULTS: The significant (p < 0.05) risk factors in present study population with their Odds Ratios (in parenthesis, respectively in Iran and India) were as follow:Lower education defined as less than class 12 or nil college (2.1) (2.7), duration of menopause greater than 5 years: (2.2) (1.4), Menarche age (after 14 years): (1.9) (1.6), Menopause age (before 45 years): (1.1) (2), Parity more than 3: (1.1) (1), Bone and joint problem (2.3) (2.2). Calcium supplementation (0.6) and HRT (0.4) were shown as protective factors and steroid therapy (3.3) was found as a risk factor in Iran. Calcium supplementation more than 1 year (0.3) was shown as a protective factor in India.Pure vegetarianism: (2.2) and Red meat consumption more than 4 times per week (1.4) was shown as a risk factor in Indian and Iranian subjects respectively. Regular consumption of Soya (0.3), almond (0.5), fish (0.5), fruits (0.4) and milk tea 4 cups per day and more (0.4) appeared to be significant protective factors in India. Regular consumption of cheese (0.5), milk (0.5), chicken (0.4), egg (0.6), fruit (0.4), tea 7 cups per day and more (0.3) were found to be significant protective factors in Iran. Exercises were shown as protective factor in Iran (0.4) and India (0.4). There were no significant differences in association of risk factors and osteoporosis between Iranian and Indian subjects. CONCLUSION: Osteoporosis in Iranian and Indian subjects also appears to be associated with several known risk factors that well described in the literature. There were no significant differences in association of risk factors and osteoporosis between Iranian and Indian subjects. It was shown a protective role of certain nutritional dietary components and also exercises in both populations and can be exploited in preventive educational strategies on osteoporosis in these populations. PMCID: PMC2289820 PMID: 18304358 Link to comment Share on other sites More sharing options...
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