51
|
Mister S, Hathcock J. Review of Supplements Ignores Evidence-Based Nutrition to Promote Tighter Regulation. JPEN J Parenter Enteral Nutr 2012; 36:265; author reply 266. [DOI: 10.1177/0148607112445507] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
|
52
|
Abstract
Nutrient intake recommendations, unlike hormone replacement standards, are based empirically, rather than physiologically, i.e., they lack an a priori normal referent. Randomized controlled trials do not provide the needed referent and are unlikely to distinguish between fully normal and various suboptimal nutritional states. Several alternative approaches, each providing an a priori normal, are described and briefly discussed.
Collapse
Affiliation(s)
- Robert P Heaney
- Creighton University Medical Center, 601 N. 30th Street, Omaha, NE 68131, USA.
| |
Collapse
|
53
|
Weseler AR, Ruijters EJB, Drittij-Reijnders MJ, Reesink KD, Haenen GRMM, Bast A. Pleiotropic benefit of monomeric and oligomeric flavanols on vascular health--a randomized controlled clinical pilot study. PLoS One 2011; 6:e28460. [PMID: 22174811 PMCID: PMC3234272 DOI: 10.1371/journal.pone.0028460] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Accepted: 11/08/2011] [Indexed: 01/22/2023] Open
Abstract
Background Cardiovascular diseases are expanding to a major social-economic burden in the Western World and undermine man's deep desire for healthy ageing. Epidemiological studies suggest that flavanol-rich foods (e.g. grapes, wine, chocolate) sustain cardiovascular health. For an evidenced-based application, however, sound clinical data on their efficacy are strongly demanded. Methods In a double-blind, randomized, placebo-controlled intervention study we supplemented 28 male smokers with 200 mg per day of monomeric and oligomeric flavanols (MOF) from grape seeds. At baseline, after 4 and 8 weeks we measured macro- and microvascular function and a cluster of systemic biomarkers for major pathological processes occurring in the vasculature: disturbances in lipid metabolism and cellular redox balance, and activation of inflammatory cells and platelets. Results In the MOF group serum total cholesterol and LDL decreased significantly (P≤0.05) by 5% (n = 11) and 7% (n = 9), respectively in volunteers with elevated baseline levels. Additionally, after 8 weeks the ratio of glutathione to glutathione disulphide in erythrocytes rose from baseline by 22% (n = 15, P<0.05) in MOF supplemented subjects. We also observed that MOF supplementation exerts anti-inflammatory effects in blood towards ex vivo added bacterial endotoxin and significantly reduces expression of inflammatory genes in leukocytes. Conversely, alterations in macro- and microvascular function, platelet aggregation, plasma levels of nitric oxide surrogates, endothelin-1, C-reactive protein, fibrinogen, prostaglandin F2alpha, plasma antioxidant capacity and gene expression levels of antioxidant defense enzymes did not reach statistical significance after 8 weeks MOF supplementation. However, integrating all measured effects into a global, so-called vascular health index revealed a significant improvement of overall vascular health by MOF compared to placebo (P≤0.05). Conclusion Our integrative multi-biomarker approach unveiled the pleiotropic vascular health benefit of an 8 weeks supplementation with 200 mg/d MOF in humans. Trial Registration ClinicalTrials.gov NCT00742287
Collapse
Affiliation(s)
- Antje R Weseler
- Department of Toxicology, Maastricht University, Maastricht, The Netherlands.
| | | | | | | | | | | |
Collapse
|
54
|
A standardised approach towards PROving the efficacy of foods and food constituents for health CLAIMs (PROCLAIM): providing guidance. Br J Nutr 2011; 106 Suppl 2:S16-28. [DOI: 10.1017/s0007114511003618] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
|
55
|
Williamson G, Coppens P, Serra-Majem L, Dew T. Review of the efficacy of green tea, isoflavones and aloe vera supplements based on randomised controlled trials. Food Funct 2011; 2:753-9. [PMID: 21927741 DOI: 10.1039/c1fo10101c] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
We assess the evidence for health benefits of three commonly consumed plant food supplements (PFS), green tea, isoflavone and aloe vera, based on published systematic reviews of randomised controlled trials (RCTs). Whilst the potential benefits of green tea have been reported in a wide range of health areas, it is only in the area of the metabolic syndrome that the number of RCTs is approaching sufficient to judge such efficacy. Isoflavone supplements are widely used, and RCTs indicate that they affect bone resorption at lower doses in postmenopausal women undergoing estrogen-related bone loss, but this is only translated to attenuation of bone loss at higher doses of isoflavones. A systematic review on RCTs concluded that the effects of isoflavones on hot flashes in postmenopausal women were highly variable and no conclusions could be drawn. Despite the popularity of aloe vera as a PFS, the evaluation of its efficacy as a coadjuvant therapy for certain metabolic or digestive pathologies remains scarce; it constitutes a typical example of a naturally occurring ingredient whose efficacy in topical applications presupposes its efficacy in systemic applications. Nevertheless, its possible toxic effects on oral consumption call for caution in its utility as a PFS. Since 2007, efficacy evaluation of PFS in Europe has been covered by European Union Nutrition and Health Claims legislation. The European Food Safety Authority has adopted an approach relying on RCTs, while medicinal effects are accepted based on traditional use. In general, there are insufficient RCTs for claims to be made, and conclusive results on PFS should be obtained in the future by conducting studies with more homogeneous populations, by using supplements with optimised and measured bioavailability, and by conducting larger RCTs.
Collapse
Affiliation(s)
- Gary Williamson
- School of Food Science and Nutrition, University of Leeds, Leeds, LS2 9JT, UK.
| | | | | | | |
Collapse
|
56
|
Abstract
In Europe, for authorisation of a health claim, applicants must follow the procedures in the legislation and in the guidelines for submission of a dossier set out by the European Food Safety Authority. The Functional Foods in Europe (FUFOSE) and Process for the Assessment of Scientific Support for Claims on Foods (PASSCLAIM) projects underpinned the laws and provided criteria against which the quality of the totality of the available data could be judged. Whereas the regulations and PASSCLAIM require an assessment of the extent to which cause and effect can be demonstrated between a food category, a food or constituent and a health benefit, the European Food Safety Authority requires conclusive evidence of cause and effect. This latter standard of proof and a focus on randomised controlled trials done on isolated components and using validated physiological biomarkers may not always be appropriate to assess nutrition science. The aims of this paper are to address the strengths and weaknesses of different sources of evidence that contribute to the totality of the available data, to undertake a critical examination of the application of a drug-like assessment model in evidence-based nutrition and to encourage research on new biomarkers of health and homeostatic adaptability. There is a need for (a) a robust and pragmatic scientific framework for assessing the strength, consistency and biological plausibility of the evidence, and (b) consumer understanding research on claims that use qualifying language and/or graphics to reflect the weight of evidence. Such scientific, policy and communication approaches are proportionate and could help stimulate academic research, promote fair trade and product innovation and contribute to consumer education about food and health.
Collapse
|
57
|
Somogyi A, Hathcock J, Biesalski HK, Blumberg JB, Antoine JM, Edwards G, Prock P. Scientific issues related to Codex Alimentarius goals: A review of principles, with examples. Regul Toxicol Pharmacol 2011; 60:161-4. [DOI: 10.1016/j.yrtph.2011.02.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Accepted: 02/22/2011] [Indexed: 11/15/2022]
|
58
|
|
59
|
Lenoir-Wijnkoop I, Dapoigny M, Dubois D, van Ganse E, Gutiérrez-Ibarluzea I, Hutton J, Jones P, Mittendorf T, Poley MJ, Salminen S, Nuijten MJC. Nutrition economics - characterising the economic and health impact of nutrition. Br J Nutr 2011; 105:157-66. [PMID: 20797310 PMCID: PMC3023144 DOI: 10.1017/s0007114510003041] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2010] [Revised: 06/24/2010] [Accepted: 07/05/2010] [Indexed: 01/24/2023]
Abstract
There is a new merging of health economics and nutrition disciplines to assess the impact of diet on health and disease prevention and to characterise the health and economic aspects of specific changes in nutritional behaviour and nutrition recommendations. A rationale exists for developing the field of nutrition economics which could offer a better understanding of both nutrition, in the context of having a significant influence on health outcomes, and economics, in order to estimate the absolute and relative monetary impact of health measures. For this purpose, an expert meeting assessed questions aimed at clarifying the scope and identifying the key issues that should be taken into consideration in developing nutrition economics as a discipline that could potentially address important questions. We propose a first multidisciplinary outline for understanding the principles and particular characteristics of this emerging field. We summarise here the concepts and the observations of workshop participants and propose a basic setting for nutrition economics and health outcomes research as a novel discipline to support nutrition, health economics and health policy development in an evidence and health-benefit-based manner.
Collapse
Affiliation(s)
- I Lenoir-Wijnkoop
- Danone Research, RD 128, 91767, Scientific Affairs, Palaiseau, France.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
60
|
Blumberg J, Heaney RP, Huncharek M, Scholl T, Stampfer M, Vieth R, Weaver CM, Zeisel SH. Evidence-based criteria in the nutritional context. Nutr Rev 2010; 68:478-84. [PMID: 20646225 DOI: 10.1111/j.1753-4887.2010.00307.x] [Citation(s) in RCA: 119] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
During the last decade, approaches to evidence-based medicine, with its heavy reliance on the randomized clinical trial (RCT), have been adapted to nutrition science and policy. However, there are distinct differences between the evidence that can be obtained for the testing of drugs using RCTs and those needed for the development of nutrient requirements or dietary guidelines. Although RCTs present one approach toward understanding the efficacy of nutrient interventions, the innate complexities of nutrient actions and interactions cannot always be adequately addressed through any single research design. Because of the limitations inherent in RCTs, particularly of nutrients, it is suggested that nutrient policy decisions will have to be made using the totality of the available evidence. This may mean action at a level of certainty that is different from what would be needed in the evaluation of drug efficacy. Similarly, it is judged that the level of confidence needed in defining nutrient requirements or dietary recommendations to prevent disease can be different from that needed to make recommendations to treat disease. In brief, advancing evidence-based nutrition will depend upon research approaches that include RCTs but go beyond them. Also necessary to this advance is the assessing, in future human studies, of covariates such as biomarkers of exposure and response, and the archiving of samples for future evaluation by emerging technologies.
Collapse
Affiliation(s)
- Jeffrey Blumberg
- Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Boston, Massachusetts, USA
| | | | | | | | | | | | | | | |
Collapse
|
61
|
Biesalski HK, Grune T, Tinz J, Zöllner I, Blumberg JB. Reexamination of a meta-analysis of the effect of antioxidant supplementation on mortality and health in randomized trials. Nutrients 2010; 2:929-49. [PMID: 22254063 PMCID: PMC3257709 DOI: 10.3390/nu2090929] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Revised: 08/17/2010] [Accepted: 08/26/2010] [Indexed: 12/14/2022] Open
Abstract
A recent meta-analysis of selected randomized clinical trials (RCTs), in which population groups of differing ages and health status were supplemented with various doses of β-carotene, vitamin A, and/or vitamin E, found that these interventions increased all-cause mortality. However, this meta-analysis did not consider the rationale of the constituent RCTs for antioxidant supplementation, none of which included mortality as a primary outcome. As the rationale for these trials was to test the hypothesis of a potential benefit of antioxidant supplementation, an alternative approach to a systematic evaluation of these RCTs would be to evaluate this outcome relative to the putative risk of greater total mortality. Thus, we examined these data based on the primary outcome of the 66 RCTs included in the meta-analysis via a decision analysis to identify whether the results provided a positive (i.e., benefit), null or negative (i.e., harm) outcome. Our evaluation indicated that of these RCTs, 24 had a positive outcome, 39 had a null outcome, and 3 had a negative outcome. We further categorized these interventions as primary (risk reduction in healthy populations) or secondary (slowing pathogenesis or preventing recurrent events and/or cause-specific mortality) prevention or therapeutic (treatment to improve quality of life, limit complications, and/or provide rehabilitation) studies, and determined positive outcomes in 8 of 20 primary prevention studies, 10 of 34 secondary prevention studies, and 6 out of 16 therapeutic studies. Seven of the eight RCTs with a positive outcome in primary prevention included participants in a population where malnutrition is frequently described. These results suggest that analyses of potential risks from antioxidant supplementation should be placed in the context of a benefit/risk ratio.
Collapse
Affiliation(s)
- Hans K. Biesalski
- Department of Biological Chemistry and Nutritional Science, University of Hohenheim, Garbenstrasse 28, D-70593 Stuttgart, Germany;
| | - Tilman Grune
- Department of Nutritional Toxicology, Friedrich Schiller University Jena, Dornburger Strasse 24, D-07743 Jena, Germany;
| | - Jana Tinz
- Department of Biological Chemistry and Nutritional Science, University of Hohenheim, Garbenstrasse 28, D-70593 Stuttgart, Germany;
| | - Iris Zöllner
- Department of Epidemiology, Baden-Wuerttemberg State Health Office, Nordbahnhofstr. 135, D-70191 Stuttgart, Germany;
| | - Jeffrey B. Blumberg
- Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA 02111, USA;
| |
Collapse
|
62
|
Linday LA, Umhau JC, Shindledecker RD, Dolitsky JN, Holick MF. Cod Liver Oil, the Ratio of Vitamins A and D, Frequent Respiratory Tract Infections, and Vitamin D Deficiency in Young Children in the United States. Ann Otol Rhinol Laryngol 2010; 119:64-70. [DOI: 10.1177/000348941011900112] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
|
63
|
Richardson DP. Health claims on foods: strength of the evidence and problems of proof. ACTA ACUST UNITED AC 2009. [DOI: 10.1616/1476-2137.15726] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
64
|
Providing expert nutrition advice: How do we know what is best? Nutr Diet 2009. [DOI: 10.1111/j.1747-0080.2009.01345.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
65
|
Heaney RP, Rafferty K. Preponderance of the evidence: an example from the issue of calcium intake and body composition. Nutr Rev 2009; 67:32-9. [PMID: 19146504 DOI: 10.1111/j.1753-4887.2008.00132.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Meta-analysis is typically applied to studies developed in fairly mature fields, but may be ill-suited for younger fields in which most of the evidence comes from studies that were designed for other endpoints entirely and that are often significantly underpowered for the effect in question. Here, there are no generally accepted methods for getting a grasp on the preponderance of the evidence. In this review, one way of doing so is proposed and the recently emergent literature concerning calcium intake and body composition is used as an illustration of how such an approach might be used.
Collapse
Affiliation(s)
- Robert P Heaney
- Creighton University Medical Center, Osteoporosis Research Center, Omaha, Nebraska 68131, USA.
| | | |
Collapse
|
66
|
van Staveren WA, Steijns JM, de Groot LC. Dairy Products as Essential Contributors of (Micro-) Nutrients in Reference Food Patterns: An Outline for Elderly People. J Am Coll Nutr 2008; 27:747S-54S. [DOI: 10.1080/07315724.2008.10719753] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
|