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Paradigms and Paradoxes Last month Dr. Armin Zittermann of Ruhr University, Germany, published the best vitamin D paper of the month. He reviewed the mounting evidence that vitamin D deficiency is a major cause of heart disease. Zittermann A, Schleithoff SS, Koerfer R. Putting cardiovascular disease and vitamin D insufficiency into perspective. Br J Nutr. 2005 Oct;94(4):483-92. Before we start, let's talk about paradigms and paradoxes. A paradigm is a set of assumptions, concepts, and practices that constitutes a way of viewing reality. The current paradigm is that heart disease is caused by a combination of genetics, hypertension, diabetes, cholesterol, smoking, obesity, inactivity, and diet. A paradox is a fact that contradicts the paradigm.

The clinical importance of vitamin D (cholecalciferol): a paradigm shift with implications for all healthcare providers. Vasquez A, Manso G, Cannell J. Altern Ther Health Med. 2004 Sep-Oct;10(5):28-36; quiz 37, 94. Review. PMID: 15478784

Vitamin D, nutritional deficiency, and the medical paradigm. Heaney RP. J Clin Endocrinol Metab. 2003 Nov;88(11):5107-8. Review. No abstract available. PMID: 14602734

Wang M. Extending the good diet, good health paradigm: modulation of breast cancer resistance protein (BCRP) by flavonoids. Toxicol Sci. 2007 Apr;96(2):203-5. PMID: 17407835 [PubMed - in process]

Current impediments to acceptance of the ultraviolet-B-vitamin D-cancer hypothesis. Grant WB, Boucher BJ. Anticancer Res. 2009 Sep;29(9):3597-604. PMID: 19667154 The ultraviolet-B (UVB)-vitamin D-cancer hypothesis was proposed in 1980. There have been numerous ecological, observational and other studies of the hypothesis. There are about 14 types of cancer for which it seems to apply: bladder, breast, colon, endometrial, esophageal, gallbladder, gastric, ovarian, pancreatic, rectal, renal and vulvar cancer and both Hodgkin's and non-Hodgkin's lymphoma. Nonetheless, the hypothesis has not yet been accepted by public health agencies. Some of the reasons for this include a distrust of ecological studies, some mistrust of observational studies, and the existence of just one positive randomized controlled trial, an analysis of a vitamin D and calcium supplementation study involving post-menopausal women in Nebraska. Paradigm shifts such as this generally take time, in part due to opposition from those content with the status quo. In this paper, results of ecological studies in the United States using summertime solar UVB as the index of vitamin D production, which is highly asymmetrical with respect to latitude, and indices for other cancer risk-modifying factors (air pollution, alcohol consumption, dietary iron and zinc, ethnic background, socioeconomic status, smoking and urban/rural residence) are discussed in terms of supporting the hypothesis. These studies were not considered while other ecological studies were examined in recent critiques of the hypothesis. While additional randomized controlled trials would, of course, be helpful, the current evidence seems to satisfy the criteria for causality as outlined by A. Bradford Hill.

July 16, 2008 - Both a low-carbohydrate diet or a Mediterranean-style diet may be "effective alternatives" to a low-fat diet, with more favorable effects on lipids and/or glycemic control, new research suggests [1]. The two-year study, which managed to keep almost 85% of the 322 study participants on one of the three diets for the entire period, offers the hope that weight-loss diets can be tailored to personal preferences, without sacrificing efficacy, researchers say. "Several recent one-year dietary studies have led the American Diabetes Association to state in January 2008 that low-carb diets should be considered for a maximum of one year," lead author on the study, Dr Iris Shai (Ben Gurion University of the Negev, Beer-Sheva, Israel), told heartwire . "The current two-year study suggests that one low-fat diet doesn't fit all, meaning that the old paradigm should be reconsidered." Shai and colleagues publish the results of the Dietary Intervention Randomized Controlled Trial (DIRECT) in the July 17, 2008 issue of the New England Journal of Medicine

July 16, 2008 | Shelley Wood Beer-Sheva, Israel - Both a low-carbohydrate diet or a Mediterranean-style diet may be "effective alternatives" to a low-fat diet, with more favorable effects on lipids and/or glycemic control, new research suggests [1]. The two-year study, which managed to keep almost 85% of the 322 study participants on one of the three diets for the entire period, offers the hope that weight-loss diets can be tailored to personal preferences, without sacrificing efficacy, researchers say. "Several recent one-year dietary studies have led the American Diabetes Association to state in January 2008 that low-carb diets should be considered for a maximum of one year," lead author on the study, Dr Iris Shai (Ben Gurion University of the Negev, Beer-Sheva, Israel), told heartwire. "The current two-year study suggests that one low-fat diet doesn't fit all, meaning that the old paradigm should be reconsidered." Shai and colleagues publish the results of the Dietary Intervention Randomized Controlled Trial (DIRECT) in the July 17, 2008 issue of the New England Journal of Medicine

"We've been having an interesting discussion in the comments about a recently published paper by Dr. Stephen C. Benoit and colleagues (free full text). They showed that a butter-rich diet causes weight gain and insulin resistance in rats, compared to a low-fat diet or a diet based on olive oil. They published a thorough description of the diets' compositions, which is very much appreciated! They went on to show that infusing palmitic acid (a 16-carbon saturated fat) directly into the brain of rats also caused insulin resistance relative to oleic acid (an 18-carbon monounsaturated fat, like in olive oil). Here's a representation of palmitic acid. The COOH end is the acid end, and the squiggly line is the fatty end. Thus it's called a "fatty acid", various forms of which are the fat currency of the body."