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The previous chapter discussed dietary supplements, including how they are marketed. That chapter stressed that much of this marketing is based on delivering false and misleading information to potential customers. This present chapter continues the subject of how the problem of false and misleading information is widespread across many areas of nutrition. This problem has a long history across many areas of the medical sciences. In Victorian times a common belief was that masturbation was a major cause of blindness and insanity. In the 1970s, a great many people believed that if they were always feeling irritable and lacking in energy, this was a sure sign of low blood sugar. This epidemic mysteriously disappeared only to be replaced by newer epidemics such as an allergy to gluten, an overload of toxins, and a yeast infection (Candida). The scope of the problem of false and misleading information is enormous and is continuously changing. It is clearly impossible, therefore, to cover all aspects of this problem. This chapter is intended only to present some illustrative examples of the problem.

Excellent research designs are essential for efficiently and accurately answering nutrition-related questions, the answers to which in turn are used in policy making. Such policy would include advice from the perspective of health about what foods people should eat, what foods industry should supply, and whether some compounds should be consumed as dietary supplements. Areas of inquiry range from molecular mechanisms in cells, animals, and humans; to descriptions of what population groups eat; to effects of food and nutrient intake on clinical outcomes and intermediate variables; and to behaviors, policies, and cost structures that influence food preparation and consumption.

The obesity epidemic appeared in the USA in 1976–1980 and then spread across Westernized countries. This paper examines the most likely causes of the epidemic in the USA. An explanation must be consistent with the emergence of the epidemic in both genders and in all age groups and ethnicities at about the same time, and with a steady rise in the prevalence of obesity until at least 2016. The cause is closely related to changes in the American diet. There is little association with changes in the intake of fat and carbohydrate. This paper presents the opinion that the factor most closely linked to the epidemic is ultra-processed foods (UPFs) (i.e., foods with a high content of calories, salt, sugar, and fat but with very little whole foods). Of particular importance is sugar intake, especially sugar-sweetened beverages (SSBs). There is strong evidence that consumption of SSBs leads to higher energy intake and more weight gain. A similar pattern is also seen with other UPFs. Factors that probably contributed to the increased intake of UPFs include their relatively low price and the increased popularity of fast-food restaurants. Other related topics discussed include: (1) the possible importance of Farm Bills implemented by the US Department of Agriculture; (2) areas where further research is needed; (3) health hazards linked to UPFs; and (4) the need for public health measures to reduce intake of UPFs.

Background: There is controversy regarding whether Wikipedia entries in the area of health-related topics are accurate and complete. Objective: To investigate the accuracy and completeness of Wikipedia entries on nutrition. Methods: Fifty-three accurate statements were formulated. Topics covered diverse areas of nutrition. One or more search terms were developed for each statement. Wikipedia entries were identified using Google for 89 search terms. These were graded for level of accuracy and completeness. Results: The entries for 73.5% of the statements had high scores (at most only minor problems were seen). The entries for 18.9% of the statements had a lesser degree of accuracy and completeness; the most common problem was that at least one entry for a statement provided no information on the statement. Serious problems of missing information were seen with the entries for 7.6% of the statements. No errors were found in any Wikipedia entries. Conclusion: While Wikipedia entries in the area of nutrition are quite accurate and free of errors, important information is often missing. Nutrition professionals should be discouraged from relying on Wikipedia. These findings are broadly consistent with other studies of Wikipedia entries in healthrelated areas.

Compare dietary supplement use and associated factors between younger and older men exercising at gyms (Cape Town).Cross-sectional comparative study (self-administered questionnaire).Younger (21–31...

In this article, we critically evaluate the evidence relating to the effects of the Mediterranean diet (MD) on the risk of cardiovascular disease (CVD). Strong evidence indicating that the MD prevents CVD has come from prospective cohort studies. However, there is only weak supporting evidence from randomized controlled trials (RCTs) as none have compared subjects who follow an MD and those who do not. Instead, RCTs have tested the effect of 1 or 2 features of the MD. This was the case in the Prevenciόn con Dieta Mediterránea (PREDIMED) study: the major dietary change in the intervention groups was the addition of either extravirgin olive oil or nuts. Meta-analyses generally suggest that the MD causes small favorable changes in risk factors for CVD, including blood pressure, blood glucose, and waist circumference. However, the effect on blood lipids is generally weak. The MD may also decrease several biomarkers of inflammation, including C-reactive protein. The 7 key features of the MD can be divided into 2 groups. Some are clearly protective against CVD (olive oil as the main fat; high in legumes; high in fruits/vegetables/nuts; and low in meat/meat products and increased in fish). However, other features of the MD have a less clear relationship with CVD (low/moderate alcohol use, especially red wine; high in grains/cereals; and low/moderate in milk/dairy). In conclusion, the evidence indicates that the MD prevents CVD. There is a need for RCTs that test the effectiveness of the MD for preventing CVD. Key design features for such a study are proposed.

While the relationship between dietary fiber and type 2 diabetes mellitus (T2DM) has been much studied, the evidence about its role in the prevention and control of this condition has been conflicting. We critically evaluate prospective cohort studies and randomized controlled trials (RCTs) that examined insoluble/nonviscous/cereal fiber and soluble/viscous/fruit fiber in relation to risk of T2DM. Taken as a whole this evidence indicates that, in the quantities typically eaten, cereal fiber is protective against T2DM while fruit fiber gives little protection. We argue that the protective action of cereal fiber may be explained by the modulating effects of gut microbiota through mechanisms such as: 1) improving glucose tolerance via energy metabolism pathways (colonic fermentation and generation of short-chain fatty acids); 2) reducing inflammation; and 3) altering the immune response. By gaining more knowledge of specific host and gut microbial functional pathways involved in T2DM development and the potential role of cereal fiber, appropriate disease prevention and intervention strategies may be developed.

Two papers were extracted and pooled data from published sources were used to estimate the distribution of BMI values for adults living in many countries around the world. The NCD Risk Factor Collaboration and the Global Burden of Disease Study 2013 presented data for 200 and 188 countries, respectively. We extracted estimates from the two datasets for the prevalences of overweight and obesity in 28 Western countries. The two studies used similar methodology for extracting and pooling data, however the papers show serious discrepancies in several countries. Our analysis reveals the need for increased standardization of the identification and analysis of surveys of BMI distribution. This is necessary in order to facilitate comparability of study results and accurate global monitoring of obesity trends. Our findings also indicate that if findings from Western countries contain serious discrepancies, then findings from middle-income and low-income countries will likely have a poor level of accuracy as far fewer surveys of BMI distribution have been carried out.

To provide evidence of the relationship of Mediterranean diet (MD) on incidence/mortality for cardiovascular disease (CVD), coronary/ischemic heart disease (CHD)/acute myocardial infarction (AMI) and stroke (ischemic/hemorrhagic) by sex, geographic region, study design and type of MD score (MDS). We performed a systematic review and meta-analysis of observational studies. Pooled relative risks (RRs) were calculated using random-effects models. We identified 29 articles. The RR for the highest versus the lowest category of the MDS was 0.81 (95% CI 0.74–0.88) for the 11 studies that considered unspecified CVD, consistent across all strata. The corresponding pooled RR for CHD/AMI risk was 0.70 (95% CI 0.62–0.80), based on 11 studies. The inverse relationship was consistent across strata of study design, end point (incidence and mortality), sex, geographic area, and the MDS used. The overall RR for the six studies that considered unspecified stroke was 0.73 (95% CI 0.59–0.91) for the highest versus the lowest category of the MDS. The corresponding values were 0.82 (95% CI 0.73–0.92) for ischemic (five studies) and 1.01 (95% CI 0.74–1.37) for hemorrhagic stroke (four studies). Our findings indicate and further quantify that MD exerts a protective effect on the risk of CVD. This inverse association includes CHD and ischemic stroke, but apparently not hemorrhagic stroke.

Front-of-package (FOP) labels may help shoppers make healthier food choices. The objectives of this review are, first, to establish the effectiveness of different FOP labels at enabling shoppers to identify which foods are healthy and which are not healthy, and, second, to assess whether different FOP labels induce shoppers to buy healthier foods. Some labels are nutrient-specific, such as Multiple Traffic Lights (MTL) and Guideline Daily Amounts (GDA). These labels state the content per serving of energy and of several substances, most commonly saturated fat, sugar, and sodium (or salt). Warning labels are another type of nutrient-specific FOP label (e.g., for food high in added sugar). Summary labels, such as Nutri-Score and labels with stars, translate the components of the food into a single value that indicates how healthy it is. Studies on FOP labels lack consistency. The majority of such studies indicate that they help shoppers to distinguish between healthy and less healthy foods. The designs that appear to be most successful in this regard are MTL, warning labels, and Nutri-Score. Labels based on GDA or that included stars were much less successful. Many studies using a simulated shopping situation reported that shoppers exposed to FOP labels had an increased intent to purchase healthier foods. Warning labels were the most consistently successful FOP design followed by MTL, Nutri-Score, and labels that included stars, while GDA failed in almost every study. Very few studies have been carried out in real-world supermarkets; the findings indicate that FOP labels or shelf labels may achieve a small degree of success (

Little is known about food advertising in the print media in South Africa or other developing countries. We investigated the extent to which different ethnic population groups of South Africa are exposed to magazine advertising for food and beverages. Five different magazines (n = 162 issues) with the most adult readers were assessed. We identified 959 food-related advertisements. These were for food and beverages (80.9%), dietary supplements (10.4%), and slimming products (8.7%). Of the 658 advertisements for specific food and beverages, most (59.3%) were for unhealthy foods. Numerous cases of misleading health/nutrition claims were seen. Government interventions are required to reduce the advertising of unhealthy food-related products and to curb misleading advertising.

Large numbers of randomised controlled trials (RCT) have been carried out in order to investigate diet–disease relationships. This article examines eight sets of studies and compares the findings with those from epidemiological studies (cohort studies in seven of the cases). The studies cover the role of dietary factors in blood pressure, body weight, cancer and heart disease. In some cases, the findings from the two types of study are consistent, whereas in other cases the findings appear to be in conflict. A critical evaluation of this evidence suggests factors that may account for conflicting findings. Very often RCT recruit subjects with a history of the disease under study (or at high risk of it) and have a follow-up of only a few weeks or months. Cohort studies, in contrast, typically recruit healthy subjects and have a follow-up of 5–15 years. Owing to these differences, findings from RCT are not necessarily more reliable than those from well-designed prospective cohort studies. We cannot assume that the results of RCT can be freely applied beyond the specific features of the studies.

Increased spending is concentrated in only a few therapeutic categories, and these tend to be heavily marketed drugs. 3 Researchers and medical professionals have issued repeated warnings as to the excessive influence of drug companies in manipulating the prescribing habits of doctors, resulting in numerous research studies, articles, and books on the topic. 4–6 The essential argument is that drug companies, motivated by profit, are extremely successful in influencing doctors in ways that favor the pharmaceutical industry’s financial interests over the public’s health interests. Chapter 7 examines the 10 most costly drugs prescribed in Canada. The estimates are that the drug bill for these products could be reduced by 55% simply by having doctors switch to lower-cost alternatives. This means that the Canadian public spends, directly or indirectly, almost a billion dollars a year in excess and unnecessary cash transfers to the pharmaceutical industry. And this figure will certainly be an order of magnitude larger in the USA. Supporting evidence for this came from another Canadian study. 7 Researchers investigated why spending on drugs in Canada doubled between 1996 and 2003. Their analysis showed that 80% of the increase was attributed to new, high-priced, patented, me-too drugs. This scandal of massive monetary waste is due, in no small part, to the marketing strategies described in this chapter. This makes one want to reach for mouthwash, eyewash, and antacid.

During the 1970s some investigators proposed that refined carbohydrates, especially sugar and a low intake of dietary fiber, were major factors in coronary heart disease (CHD). This suggestion was eclipsed by the belief that an excess intake of saturated fatty acids (SFA) was the key dietary factor, a view that prevailed from roughly 1974 to 2014. Findings that have accumulated since 1990 inform us that the role of SFA in the causation of CHD has been much exaggerated. A switch from SFA to refined carbohydrates does not lower the ratio of total cholesterol to HDL-cholesterol in the blood and therefore does not prevent CHD. A reduced intake of SFA combined with an increased intake of polyunsaturated fatty acids lowers the ratio of total cholesterol to HDL-cholesterol; this may reduce the risk of CHD. The evidence linking carbohydrate-rich foods with CHD has been steadily strengthening. Refined carbohydrates, especially sugar-sweetened beverages, increase the risk of CHD. Conversely, whole grains and cereal fiber are protective. An extra one or 2 servings per day of these foods increases or decreases risk by approximately 10% to 20%.

The widespread consumption of alcoholic beverages and their potentially conflicting health impacts makes a discussion of this topic vitally important for physicians. Alcohol (ethanol) consumption in large quantities is strongly linked to dramatic negative health consequences. The acute effects of alcohol consumption on behavior, motor function, and health risks are plainly observed in an emergency room on a Saturday night. The long-term effects of moderate consumption—years rather than hours—are much less clinically obvious. The biological effects of a drink are mostly related to its alcohol content, alcohol metabolites, and the other substances found in alcoholic beverages (i.e., sugars and polyphenolic compounds). While the health effects of alcohol consumption is the topic of countless reviews, this chapter focuses on issues related to recommendations that physicians may give to their patients.