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Cardiovascular disease and type 2 diabetes are uncommon in people consuming vegetarian and vegan diets. Vegetarian and vegan dietary patterns tend to result in lower body weight and better nutritional profiles than conventional healthy eating patterns and have been shown to be an effective tool for management of cardiovascular disease and diabetes risk. The consistency of observed beneficial outcomes with vegetarian and vegan eating styles warrants the expansion of dietary guidelines for prevention and treatment of cardiovascular disease and diabetes to include well-planned vegetarian dietary patterns as a viable alternative to conventional dietary treatments.

This review evaluates evidence from clinical trials that assessed the effect of dairy product or calcium intake, with or without concomitant energy restriction, on body weight and adiposity. Of 49 randomized trials assessing the effect of dairy products or calcium supplementation on body weight, 41 showed no effect, two demonstrated weight gain, one showed a lower rate of gain, and five showed weight loss. Four of 24 trials report differential fat loss. Consequently, the majority of the current evidence from clinical trials does not support the hypothesis that calcium or dairy consumption aids in weight or fat loss.

Objective This study investigated the nutrient intake of overweight postmenopausal women assigned to a low-fat vegan diet or a Step II diet. Methods Fifty-nine overweight (body mass index, 26 to 44 kg/m 2 ) postmenopausal women were randomly assigned to a self-selected low-fat vegan or a National Cholesterol Education Program Step II diet in a 14-wk controlled trial on weight loss and metabolism. Nutrient intake, which was measured per 1000 kcal, was the main outcome measure. Statistical analyses included within-group and between-group t tests examining changes associated with each diet. Results Consumption of a low-fat vegan diet was associated with greater decreases in fat, saturated fat, protein, and cholesterol intakes and greater increases in carbohydrate, fiber, β-carotene, and total vitamin A intakes than was a Step II diet. The low-fat vegan group also increased thiamin, vitamin B6, and magnesium intakes more than the Step II group, and both groups increased folic acid, vitamin C, and potassium intakes. If considering only food sources of micronutrients, the low-fat vegan group decreased vitamin D, vitamin B12, calcium, selenium, phosphorous, and zinc intakes compared with baseline. However, with incidental supplements included, decreases were evident only in phosphorous and selenium intakes. No micronutrient decreases were found in the Step II group. Conclusions Individuals on a low-fat vegan or Step II diet should take steps to meet the recommended intakes of vitamin D, vitamin K, folic acid, calcium, magnesium, and zinc. Individuals on a low-fat vegan diet should also ensure adequate intakes of vitamin B12, phosphorous, and selenium.

PURPOSE This study aimed to assess the acceptability of a low-fat vegan diet, as compared with a more typical fat-modified diet, among overweight and obese adults. METHODS Through newspaper advertisements, 64 overweight, postmenopausal women were recruited, 59 of whom completed the study. The participants were assigned randomly to a low-fat vegan diet or, for comparison, to a National Cholesterol Education Program Step II (NCEP) diet. At baseline and 14 weeks later, dietary intake, dietary restraint, disinhibition, and hunger, as well as the acceptability and perceived benefits and adverse effects of each diet were assessed. RESULTS Dietary restraint increased in the NCEP group (P

Research has identified certain foods and dietary patterns that are associated with reduced cancer risk and improved survival after cancer diagnosis. This research has formed the basis for dietary guidance issued by cancer organizations. Unfortunately, gaps within nutrition research have made it difficult to make recommendations in some areas. This review specifies suggested dietary guidance in which evidence of a dietary influence on cancer risk is substantial, even if not conclusive. Evidence summaries within the review are based on the 2007 report of the World Cancer Research Fund/American Institute for Cancer Research. This review also describes advantages and disadvantages of following the suggested dietary guidance and includes putative mechanisms involved in cancer progression.Suggested dietary guidance where evidence is sufficiently compelling include (1) limiting or avoiding dairy products to reduce the risk of prostate cancer; (2) limiting or avoiding alcohol to reduce the risk of cancers of the mouth, pharynx, larynx, esophagus, colon, rectum, and breast; (3) avoiding red and processed meat to reduce the risk of cancers of the colon and rectum; (4) avoiding grilled, fried, and broiled meats to reduce the risk of cancers of the colon, rectum, breast, prostate, kidney, and pancreas; (5) consumption of soy products during adolescence to reduce the risk of breast cancer in adulthood and to reduce the risk of recurrence and mortality for women previously treated for breast cancer; and (6) emphasizing fruits and vegetables to reduce risk of several common forms of cancer.By adopting the precautionary principle for nutrition research, this review aims to serve as a useful tool for practitioners and patients.

Nutritional authorities encourage consumers to include calcium-rich foods in their daily diets. However, consumer purchases are driven not only by health considerations and dietary preferences, but also by cost. This study assessed the cost of calcium from a wide variety of food sources, as well as supplements, based on retail prices in Seattle, San Francisco, Raleigh, New York City, and Washington, D.C., while controlling for seasonal variation. Costs were adjusted based on calcium absorption fractions. Calcium carbonate supplements emerged as the least expensive source of calcium, at roughly one-third the cost of the least expensive food source of calcium. The least expensive food sources of calcium were Total® cereal, skim milk, and calcium-fortified orange juice from frozen concentrate. This information is useful for dietitians, health professionals, and consumers in meeting calcium requirements on a budget. J Am Diet Assoc. 2002; 102:1669–1671.

We summarize conclusions drawn from a panel discussion at the "Fifth International Congress on Vegetarian Nutrition" about the roles of and emphasis on food, plant food, and vegetarianism in current and future US dietary guidelines. The most general recommendation of the panel was that future dietary guidelines, following the lead of the 2005 Dietary Guidelines Advisory Committee, should emphasize food-based recommendations and thinking to the full extent that evidence allows. Although nutrient-based thinking and Dietary Reference Intakes (DRIs) may help ensure an adequate diet in the sense that deficiency states are avoided, the emphasis on DRIs may not capture many important nutritional issues and may inhibit a focus on foods. More generally, in the context of the conference on vegetarian nutrition, this report focuses on the history and structure of the Dietary Guidelines Advisory Committee, on various plant food-oriented recommendations that are supported by literature evidence, and on mechanisms for participating in the process of forming dietary guidelines. Among recommendations that likely would improve health and the environment, some are oriented toward increased plant food consumption and some toward vegetarianism. The literature on health effects of individual foods and whole lifestyle diets is insufficient and justifies a call for future food-oriented research, including expanding the evidence base for plant-based and vegetarian diets. The Dietary Guidelines Advisory Committee's role should be carried forward to creation of a publicly accessible icon (eg, the current pyramid) and related materials to ensure that the science base is fully translated for the public.

Data supporting the inverse correlation of fish or long-chain omega-3 fatty acid (FA) (eicosapentaenoic acid plus docosahexaenoic acid) supplement consumption and coronary heart disease are inconclusive and may be confounded by other dietary and lifestyle factors. Using the Diabetic Control and Complications Trial (DCCT) database (n = 1,441), correlations between consumption of omega-3 FAs and saturated FAs to dietary variables (kilocalories, macronutrients, sodium, and cholesterol) and to age, gender, exercise level, and tobacco use were tested using Pearson correlation coefficients. Long-chain omega-3 FA intake inversely correlated with consumption of calories (r = -0.16, p0.0001), percent calories from total fat (r = -0.14, p0.0001), and percent calories from saturated FAs (r = -0.21, p0.0001) and directly with dietary fiber intake (grams per 1,000 kcal, r = 0.20, p0.0001). In the DCCT database, long-chain omega-3 FAs (i.e., fish consumption) inversely correlated with an overall low risk nutritional profile for coronary heart disease. In conclusion, these findings provide evidence that associations observed in studies suggesting a benefit of fish or long-chain omega-3 FAs may be due to a convergence of greater fish intakes with an overall healthier dietary pattern rather than with a specific effect of long-chain omega-3 FAs.

Objective. Numerous nutrition policy statements recommend the consumption of 800 to 1500 mg of calcium largely from dairy products for osteoporosis prevention; however, the findings of epidemiologic and prospective studies have raised questions about the efficacy of the use of dairy products for the promotion of bone health. The objective of this study was to review existing literature on the effects of dairy products and total dietary calcium on bone integrity in children and young adults to assess whether evidence supports (1) current recommended calcium intake levels and (2) the suggestion that dairy products are better for promoting bone integrity than other calcium-containing food sources or supplements.Methods. A Medline (National Library of Medicine, Bethesda, MD) search was conducted for studies published on the relationship between milk, dairy products, or calcium intake and bone mineralization or fracture risk in children and young adults (1–25 years). This search yielded 58 studies: 22 cross-sectional studies; 13 retrospective studies; 10 longitudinal prospective studies; and 13 randomized, controlled trials.Results. Eleven of the studies did not control for weight, pubertal status, and exercise and were excluded. Ten studies were randomized, controlled trials of supplemental calcium, 9 of which showed modest positive benefits on bone mineralization in children and adolescents. Of the remaining 37 studies of dairy or unsupplemented dietary calcium intake, 27 studies found no relationship between dairy or dietary calcium intake and measures of bone health. In the remaining 9 reports, the effects on bone health are small and 3 were confounded by vitamin D intake from milk fortified with vitamin D. Therefore, in clinical, longitudinal, retrospective, and cross-sectional studies, neither increased consumption of dairy products, specifically, nor total dietary calcium consumption has shown even a modestly consistent benefit for child or young adult bone health.Conclusion. Scant evidence supports nutrition guidelines focused specifically on increasing milk or other dairy product intake for promoting child and adolescent bone mineralization.

Dairy products are the main source of calcium in the National School Lunch Program. Children who avoid dairy products because of lactose intolerance or other concerns can benefit from the availability of another calcium-rich beverage in the National School Lunch Program. This study assessed whether elementary school children would select and consume calcium-fortified soymilk in school cafeterias and whether the addition of soymilk would increase the percentage of students selecting a calcium-rich beverage at lunch. The ratio of saturated fat to calcium consumed from calcium-rich beverages with and without the availability of soymilk was also determined. After 4 weeks of soymilk availability, 22.3% of students chose soymilk and consumed an average of 58% of each carton, whereas 77.6% chose dairy milk and consumed an average of 52.6%. Total calcium-rich beverage selection with lunch increased from 79% to 83.1%. Calcium consumption per gram of saturated fat consumed from calcium-rich beverages also rose from 194 mg to 237 mg with the addition of soymilk.

Conventional wisdom, public policy on nutrition in many westernised countries, and advertisements for dairy products link increased consumption of calcium to better bone health and prevention of osteoporosis in later life. However, a meta-analysis by Winzenberg and colleagues in this week's BMJ shows that calcium supplementation in children is unlikely to result in a clinically relevant decrease in the risk of fracture in childhood or in later life.1 Previous research has questioned whether increasing calcium intake through diet or supplements benefits children's or young adults' bones. Exercise significantly increased bone density and bone strength, but calcium intake between 500 and 1500 mg had no effect on the same outcomes in adolescent girls studied prospectively for 12 years as they passed into young adulthood.2 Of three qualitative reviews of literature published in this decade, two concluded that it is not known whether the modest increments in rate of bone gain after supplementation with calcium or dairy produce will translate into clinically meaningful reductions in the risk of osteoporosis later in life or even persist beyond the treatment period.3,4 The third concluded that increases in dairy or total dietary calcium intake did not reliably increase bone mineral density or reduce fracture rate in children or adolescents.5 None the less, the recommended intake of calcium in children remains high in the United Kingdom, the European Union, Australia, the United States, and Canada (350-800 mg/day for children and 800-1300 for adolescents).6 Consequently, policy guidelines and nutrition programmes promote the intake of two to four servings of dairy products daily. For example, the US government promotes the consumption of three or more servings of cow's milk or other dairy products daily, and it subsidises the distribution of dairy products through the national school lunch programme and the women's, infants', and children's nutrition programme. The justification has been to avert a so called “calcium crisis” (a mismatch between calcium intake and recommendations) thought to be responsible for high rates of osteoporosis later in life. What if we—researchers, paediatricians, marketers, and policy experts—have been wrong? What if increasing calcium intake in youth has no significant impact on fracture risk in early or later life as Winzenberg and colleagues conclude? Populations that consume the most cow's milk and other dairy products have among the highest rates of osteoporosis and hip fracture in later life.6,7 Given this fact, it is important to ask whether sufficient evidence exists to continue assuming that consumption of these foods is part of the solution. Furthermore, we need to ask the question of whether we are doing children a disservice by encouraging them to meet recommendations. Childhood obesity is on the rise in westernised countries, and dairy products—the main source of calcium recommended by nutrition guidelines—contribute greatly to the intake of fat and sugar in children.8 Nearly three quarters of the world's population are estimated to be lactose intolerant after the age of weaning and therefore do not tolerate the consumption of milk and other dairy products well. In addition, some studies suggest that the consumption of cow's milk increases the risk of some types of cancer.9,10 The meta-analysis by Winzenberg and colleagues strengthens previous evidence that calcium or dairy products do not have a clinically relevant impact on bone health in youth. The focus on calcium recommendations in nutrition policy and research draws attention away from more comprehensive research on how to promote long term bone health among young people. Public health would be better served by researching how other dietary and lifestyle factors affect children's bones. Promising areas include the effect of regular exercise, vitamin D status, increasing fruit and vegetable consumption, limiting salt intake, limiting or avoiding animal protein, and avoiding smoking. It is time to revise our calcium recommendations for young people and change our assumptions about the role of calcium, milk, and other dairy products in the bone health of children and adolescents. While the policy experts work on revising recommendations, doctors and other health professionals should encourage children to spend time in active play or sports, and to consume a nutritious diet built from whole foods from plant sources to achieve and maintain a healthy weight and provide an environment conducive to building strong bones.

Weanling Dahl salt-sensitive (DS) and salt-resistant (DR) rats were used to compare effects of feeding high or low NaCl diets on taste preference for, and intake of, a wide range of saline concentrations. The DS and DR were fed either 8.0 or 0.4% dietary NaCl for 4 weeks. Then, with all animals fed the 0.4% NaCl diet, their taste preferences for 0.0001 to 0.56 M saline were assessed using three 24-hour two-bottle preference tests of each solution versus distilled deionized water. Saline preference and intake were influenced by concentration and its interaction with genotype, with DS exhibiting higher preferences than DR for hypotonic saline. The DS preexposed to 8.0% dietary NaCl showed elevated consumption levels of water and total fluid (saline + water) that persisted throughout the 5-week test period, despite transfer to the 0.4% NaCl diet before the initiation of preference testing. Findings indicate that genotype, dietary NaCl levels in weaning diet, and saline concentration of preference test solutions interact to influence saline preference and saline and water intake in Dahl rats.