Impact of Cranberries on Gut Microbiota and Cardiometabolic Health: Proceedings of the Cranberry Health Research Conference 2015.

Recent advances in cranberry research have expanded the evidence for the role of this Vaccinium berry fruit in modulating gut microbiota function and cardiometabolic risk factors. The A-type structure of cranberry proanthocyanidins seems to be responsible for much of this fruit's efficacy as a natural antimicrobial. Cranberry proanthocyanidins interfere with colonization of the gut by extraintestinal pathogenic Escherichia coli in vitro and attenuate gut barrier dysfunction caused by dietary insults in vivo. Furthermore, new studies indicate synergy between these proanthocyanidins, other cranberry components such as isoprenoids and xyloglucans, and gut microbiota. Together, cranberry constituents and their bioactive catabolites have been found to contribute to mechanisms affecting bacterial adhesion, coaggregation, and biofilm formation that may underlie potential clinical benefits on gastrointestinal and urinary tract infections, as well as on systemic anti-inflammatory actions mediated via the gut microbiome. A limited but growing body of evidence from randomized clinical trials reveals favorable effects of cranberry consumption on measures of cardiometabolic health, including serum lipid profiles, blood pressure, endothelial function, glucoregulation, and a variety of biomarkers of inflammation and oxidative stress. These results warrant further research, particularly studies dedicated to the elucidation of dose-response relations, pharmacokinetic/metabolomics profiles, and relevant biomarkers of action with the use of fully characterized cranberry products. Freeze-dried whole cranberry powder and a matched placebo were recently made available to investigators to facilitate such work, including interlaboratory comparability.

Squeezing fact from fiction about 100% fruit juice.

Total fruit intake in the United States is ~1 cup equivalent per day, or one-half of the 2010 Dietary Guidelines for Americans recommendation for adults. Two-thirds of the fruit consumed is whole fruit and one-third is 100% juice. The nutritional value of whole fruit, with the exception of fiber and vitamin C, may be retained with appropriate juice production methods and storage conditions. One-hundred percent fruit juice consumption is associated with a number of health benefits, such as improved cardiovascular health and decreased obesity, although some of these and other potential benefits are controversial. Comprehensive analyses of the evidence by the Academy of Nutrition and Dietetics in 2014, the US Dietary Guidelines Advisory Committee in 2010, and the Australian Dietary Guidelines of 2013 concluded that 100% fruit juice is not related to adiposity in children when consumed in appropriate amounts for age and energy needs. However, some reports suggest the consumption of fruit juice contributes to unhealthful outcomes, particularly among children. A dietary modeling study on the best ways to meet the fruit intake shortfall showed that a combination of whole fruit and 100% juice improved dietary density of potassium and vitamin C without significantly increasing total calories. Notably, 100% juice intake was capped at amounts consistent with the 2001 American Pediatric Association guidance. The preponderance of evidence supports the position that 100% fruit juice delivers essential nutrients and phytonutrients, provides year-round access to a variety of fruits, and is a cost-effective way to help people meet fruit recommendations.

Communicating clinical research to reduce cancer risk through diet: Walnuts as a case example.

Inflammation is one mechanism through which cancer is initiated and progresses, and is implicated in the etiology of other conditions that affect cancer risk and prognosis, such as type 2 diabetes, cardiovascular disease, and visceral obesity. Emerging human evidence, primarily epidemiological, suggests that walnuts impact risk of these chronic diseases via inflammation. The published literature documents associations between walnut consumption and reduced risk of cancer, and mortality from cancer, diabetes, and cardiovascular disease, particularly within the context of the Mediterranean Diet. While encouraging, follow-up in human intervention trials is needed to better elucidate any potential cancer prevention effect of walnuts, per se. In humans, the far-reaching positive effects of a plant-based diet that includes walnuts may be the most critical message for the public. Indeed, appropriate translation of nutrition research is essential for facilitating healthful consumer dietary behavior. This paper will explore the translation and application of human evidence regarding connections with cancer and biomarkers of inflammation to the development of dietary guidance for the public and individualized dietary advice. Strategies for encouraging dietary patterns that may reduce cancer risk will be explored.

Mushrooms and Health Summit proceedings.

The Mushroom Council convened the Mushrooms and Health Summit in Washington, DC, on 9-10 September 2013. The proceedings are synthesized in this article. Although mushrooms have long been regarded as health-promoting foods, research specific to their role in a healthful diet and in health promotion has advanced in the past decade. The earliest mushroom cultivation was documented in China, which remains among the top global mushroom producers, along with the United States, Italy, The Netherlands, and Poland. Although considered a vegetable in dietary advice, mushrooms are fungi, set apart by vitamin B-12 in very low quantity but in the same form found in meat, ergosterol converted with UV light to vitamin D2, and conjugated linoleic acid. Mushrooms are a rare source of ergothioneine as well as selenium, fiber, and several other vitamins and minerals. Some preclinical and clinical studies suggest impacts of mushrooms on cognition, weight management, oral health, and cancer risk. Preliminary evidence suggests that mushrooms may support healthy immune and inflammatory responses through interaction with the gut microbiota, enhancing development of adaptive immunity, and improved immune cell functionality. In addition to imparting direct nutritional and health benefits, analysis of U.S. food intake survey data reveals that mushrooms are associated with higher dietary quality. Also, early sensory research suggests that mushrooms blended with meats and lower sodium dishes are well liked and may help to reduce intakes of red meat and salt without compromising taste. As research progresses on the specific health effects of mushrooms, there is a need for effective communication efforts to leverage mushrooms to improve overall dietary quality.

The art of translating nutritional science into dietary guidance: history and evolution of the Dietary Guidelines for Americans.

The United States government has published official Dietary Guidelines for Americans (DGA) since 1980 and has recently released the 2010 version. Serving as a foundational cornerstone for federal nutrition policy, the DGA embrace current nutritional science and translate it into practical guidance to enhance the overall health of Americans. This article reviews the history and process for developing the DGA, including the incorporation of sophisticated and systematic techniques for reviewing emerging evidence. It also explores issues related to implementation of the guidelines through federal policy, the food supply, and consumer knowledge and behavior.

The vitamin D and cancer conundrum: aiming at a moving target.

The case for the influence of vitamin D on health, including cancer prevention, is increasingly compelling. While some are calling for increases in the Tolerable Upper Intake Level, fortification, and dietary supplementation, questions regarding dose and individual response variability continue to merit attention. Colorectal cancer risk reduction with adequate vitamin D status is well documented. Protection has also been observed for cancer at all sites, skin, prostate, and breast. At the same time, some individuals may be adversely affected by elevated 25(OH)D concentrations with respect to risk of cancers of the prostate, breast, pancreas, and esophagus, and in some cases a U- or J-shaped association has been suggested. Future research should seek to clarify if and for whom there may be an increased risk for cancer at particular sites with high 25(OH)D concentrations, and the concentrations at which risk increases. Fundamentally, prospective longitudinal studies of these relationships are warranted. The health status, life stage, adiposity, estrogen exposure, and nutritional status of study participants should be taken into account. Continued investigation is necessary to ensure that vitamin D recommendations are appropriately targeted to individuals who stand to benefit most, while protecting vulnerable subgroups from risk of overexposure.

Towards establishing dietary reference intakes for eicosapentaenoic and docosahexaenoic acids.

There is considerable interest in the impact of (n-3) long-chain PUFA in mitigating the morbidity and mortality caused by chronic diseases. In 2002, the Institute of Medicine concluded that insufficient data were available to define Dietary Reference Intakes (DRI) for eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA), noting only that EPA and DHA could contribute up to 10% toward meeting the Adequate Intake for alpha-linolenic acid. Since then, substantial new evidence has emerged supporting the need to reassess this recommendation. Therefore, the Technical Committee on Dietary Lipids of the International Life Sciences Institute North America sponsored a workshop on 4-5 June 2008 to consider whether the body of evidence specific to the major chronic diseases in the United States--coronary heart disease (CHD), cancer, and cognitive decline--had evolved sufficiently to justify reconsideration of DRI for EPA+DHA. The workshop participants arrived at these conclusions: 1) consistent evidence from multiple research paradigms demonstrates a clear, inverse relation between EPA+DHA intake and risk of fatal (and possibly nonfatal) CHD, providing evidence that supports a nutritionally achievable DRI for EPA+DHA between 250 and 500 mg/d; 2) because of the demonstrated low conversion from dietary ALA, protective tissue levels of EPA+DHA can be achieved only through direct consumption of these fatty acids; 3) evidence of beneficial effects of EPA+DHA on cognitive decline are emerging but are not yet sufficient to support an intake level different from that needed to achieve CHD risk reduction; 4) EPA+DHA do not appear to reduce risk for cancer; and 5) there is no evidence that intakes of EPA+DHA in these recommended ranges are harmful.