Alexa L. Meyer

Body composition, changing physiological functions and nutrient requirements of the elderly.

Age has an important impact on body composition. The decreases of lean body mass and total body water accompanied by an increase of body fat are the most relevant changes leading to a reduction of the basal metabolic rate. Due to this and the fact that elderly people are generally less physically active, energy needs are lower. However, the requirements for most micronutrients are not reduced. Indeed, impaired absorption of some vitamins and minerals like cobalamin and calcium can cause deficiencies. An adequate calcium supply is particularly important as with ongoing age, bone mass decreases as well, making elderly prone to osteoporosis. The reduced ability to synthesize vitamin D and the lower sunlight exposure of many elderly further aggravate this issue. There is evidence to consider the supply of some important dietary antioxidants as critical in some elderly, namely vitamin C and β-carotene as well as zinc. In light of age-related decreases in the activities of antioxidant enzymes, a sufficient supply of dietary antioxidants is important, especially as oxidative damage is thought to contribute to the deteriorating processes associated with aging and promote cardiovascular disease, cognitive disorders, cancer and diabetes mellitus that occur more frequently in older people. The first three are also associated with an insufficiency of folate, another critical nutrient in the elderly. Therefore, dietary guidelines should strive to optimize the immune function and reduce disease risk of the elderly.

Immune-stimulating effects of lactic acid bacteria in vivo and in vitro.

The health-promoting effects of lactic acid bacteria (LAB) are well recognised, making them a popular functional food ingredient. Commercially available probiotic products are often promoted as capable of improving immune defences also in healthy subjects. However, while strain-specific differences exist in the effects of LAB, conventional yoghurt bacteria have proved beneficial as well. For comparing the immunological effects of conventional and probiotic LAB, young healthy women received either a commercially available probiotic fermented milk product or a conventional yoghurt for four weeks. Both treatments showed comparable effects resulting in a stronger immunological reaction to stimuli (natural cytotoxicity against cancer cells, mitogen-induced T-lymphocyte activation and stimulated cytokine production). To study the mechanisms behind these effects, conventional (Lactobacillus delbrueckii) and probiotic (Lactobacillus rhamnosus GG), LAB were compared in vitro at the cellular level. Interestingly, L. rhamnosus GG was more potent in inducing maturation of dendritic cells (DC) that play a substantial role in directing the immune response to stimuli. In turn, L. delbrueckii provoked a higher secretion of proinflammatory cytokines as well as IL-10. These effects were, however, observed only after direct incubation of DC and LAB, not when both were separated by a layer of enterocyte-like Caco-2 cells. LAB also induced cytokine secretion in peripheral blood mononuclear cells in a similar manner and this effect was reduced in a Caco-2 cell model, suggesting a modulating influence of gut epithelial cells. While both conventional and probiotic strains modulate the immune response, specific properties may offer therapeutic options in the treatment of certain diseases.

Daily Intake of Probiotic as well as Conventional Yogurt Has a Stimulating Effect on Cellular Immunity in Young Healthy Women

Background/Aims: The aim of this work was to study the effects of daily yogurt consumption on the cellular immunity of young healthy women and to compare a conventional with a probiotic product. Methods: 33 young healthy women (22–29 years) consumed 100 g/day of either probiotic or conventional commercially available yogurt for 2 weeks and 200 g/day for another 2 weeks followed by a 2-week washout period with no fermented food at all. Before the intervention and after each phase, a complete white blood count was done, the percentage of activated CD69+ T lymphocytes after stimulation of whole blood with pokeweed mitogen was determined as well as the natural cytotoxicity of peripheral blood mononuclear cells against a human erythroleukemic target cell line (K562). All analyses were done by flow cytometry. Results: In the probiotic group only, the numbers of cytotoxic T lymphocytes (CD3+CD16+CD56+) increased significantly (+30.8% with p = 0.001, +22.1 and +32.7% with p = 0.002, for T2, T3 and T4 compared to T1). There were no major changes for other cell populations, and all remained within the physiological range. In both groups, the expression of CD69 on T lymphocytes increased after yogurt consumption, especially on CD8+ (conventional: T2 +23%, T3 +27.2%, probiotic: T2 +15.7%; T3 +10.8% compared to T1) and to a lesser extent on CD4+ (conventional: T2 +7.7%, T3 +14.9%, probiotic: T2 +4% compared to T1. The cytotoxic activity also augmented following the intake, this effect persisting after cessation of consumption. However, there were no significant differences between the probiotic and the conventional yogurt group. Conclusion: Daily yogurt intake has a stimulating effect on cellular immune functions, but in this study the probiotic product did not perform better than the traditional one.

Vitamins for the First 1000 Days: Preparing for Life

Vitamins are essential nutrients for many body functions and particularly important during growth. Adequate supply in pregnancy and in early infancy is therefore crucial, but there is still a lack of knowledge about the needed amounts of vitamins of children older than six months and also during pregnancy. Recommendations for intake levels are generally derived by extrapolation from data for infants based in turn on the contents in breast milk and those for adults. A vitamin of particular importance in pregnancy is folic acid due to its role in the development of the brain and nerve system and the prevention of fetal neural tube defects (NTD). Mandatory fortification of flour and certain other grain products in many countries has been associated with a reduction in NTD incidence. However, other deficiencies or suboptimal status of B vitamins, especially B6 and B12 have been repeatedly reported in pregnant women also in high-income countries. Vitamin A is one of the three most critical micronutrients globally and pregnant women and young children are especially vulnerable to deficiencies. Night blindness, anemia, and immunodeficiency are major consequences of inadequate supply in these populations. Much attention has recently been accorded vitamin D that is also critical in pregnant women and young children for instance because of its involvement in bone mineralization but also its more recently discovered immune-modulating function that is thought to prevent development of autoimmune diseases like diabetes mellitus type I. A healthy balanced diet provides the best basis for optimal pregnancy outcome, lactation performance, and complementary feeding. However, supplements or fortified foods may be needed to cover the high requirements especially of critical vitamins such as vitamin D and folic acid and to correct unfavorable dietary patterns in women or to adapt foods to the needs of young children.

The role of dietary potassium in hypertension and diabetes

Potassium is an essential mineral which plays major roles for the resting membrane potential and the intracellular osmolarity. In addition, for several years, it has been known that potassium also affects endothelial and vascular smooth muscle functions and it has been repeatedly shown that an increase in potassium intake shifts blood pressure to a more preferable level. Meanwhile, the blood pressure lowering effects of potassium were presented in several intervention trials and summarized in a handful of meta-analyses. Furthermore, accumulating epidemiological evidence from, especially, the last decade relates low dietary potassium intake or serum potassium levels to an increased risk for insulin resistance or diabetes. However, intervention trials are required to confirm this association. So, in addition to reduction of sodium intake, increasing dietary potassium intake may positively affect blood pressure and possibly also glucose metabolism in many populations. This concise review not only summarizes the studies linking potassium to blood pressure and diabetes but also discusses potential mechanisms involved, like vascular smooth muscle relaxation and endothelium-dependent vasodilation or stimulation of insulin secretion in pancreatic β-cells, respectively.

Patterns of drinking and eating across the European Union: implications for hydration status.

Appropriate hydration is essential for health and well-being. In Europe, water consumption patterns vary despite the unlimited availability of this resource. Water constitutes the largest proportion of total fluid intake in most countries. According to the 2008 European Food Safety Authoritys Concise Food Consumption Database, tap water consumption was highest in the northern European countries and in Austria. While Germany had a particularly low intake of tap water, it led in consumption of fruit and vegetable juices, soft drinks, and especially bottled water. European nutrition surveys generally report an average fluid intake within the recommended range of 1500-2000 mL/day, with higher intake levels corresponding with increasing frequency of intake. However, some population groups consume less than others, e.g., the elderly who are at higher risk for dehydration due to age-related increased urinary fluid losses. In turn, physical activity is associated with higher beverage consumption as is adherence to a health-conscious diet. While water constitutes the most commonly consumed beverage throughout Europe, drinking patterns and quantities vary and are influenced by a variety of factors, including age, gender, diet, and physical activity level.

Animal Proteins as Important Contributors to a Healthy Human Diet

Adequate protein intake is critical for health and development. Generally, protein of animal origin is of higher quality for humans owing to its amino acid pattern and good digestibility. When administered in mixtures it can enhance the quality of plant proteins, but its availability is often low in low-income communities, especially in young children, the elderly, and pregnant and lactating women, who have increased requirements and in whom high-quality protein also stimulates (bone) growth and maintenance. Although high protein intake was associated with increased type 2 diabetes mellitus risk, milk and seafood are good sources of branched chain amino acids and taurine, which act beneficially on glucose metabolism and blood pressure. However, high consumption of protein-rich animal food is also associated with adverse health effects and higher risk for noncommunicable diseases, partly related to other components of these foods, like saturated fatty acids and potential carcinogens in processed meat but also the atherogenic methionine metabolite homocysteine. In moderation, however, animal proteins are especially important for health maintenance in vulnerable persons.

Diet Quality, a Term Subject to Change over Time

A high-quality diet is one of the foundations of health and well-being. For a long time in human history, diet was chiefly a source of energy and macronutrients meant to still hunger and give the strength for work and activities that were in general much harder than nowadays. Only few persons could afford to emphasize enjoyment. In the assessment of quality, organoleptic properties were major criteria to detect spoilage and oxidative deterioration of food. Today, food hygiene is a quality aspect that is often taken for granted by consumers, despite its lack being at the origin of most food-borne diseases. The discovery of micronutrients entailed fundamental changes of the concept of diet quality. However, non-essential food components with additional health functions were still barely known or not considered important until recently. With the high burden of obesity and its associated diseases on the rise, affluent, industrialized countries have developed an increased interest in these substances, which has led to the development of functional foods to optimize special body functions, reduce disease risk, or even contribute to therapeutic approaches. Indeed, nowadays, high contents of energy, fat, and sugar are factors associated with a lower quality of food, and products with reduced amounts of these components are valued by many consumers. At the same time, enjoyment and convenience are important quality factors, presenting food manufacturers with the dilemma of reconciling low fat content and applicability with good taste and appealing appearance. Functional foods offer an approach to address this challenge. Deeper insights into nutrient-gene interactions may enable personalized nutrition adapted to the special needs of individuals. However, so far, a varied healthy diet remains the best basis for health and well-being.

Nutritional indicators and health aspects of fruit and vegetable consumption in aged adults

Abstract Age-related physiological changes also affect nutritional status. Fruits and vegetables play an important role in the diet of the elderly being rich in many micronutrients often critical in older persons. Due to their low-energy content, they reveal a high-nutrient density, making them a good choice considering the age-related decrease of energy needs. Moreover, nonnutritive bioactive secondary plant compounds act on many pathways associated with the health decline of aging. They stimulate the immune system, mitigate proinflammatory events and oxidative stress. Additionally, fruits and vegetables are a major source of dietary fiber promoting a healthy gut flora and endothelium. Fruit and vegetable consumption in industrialized countries is generally unsatisfactory despite a trend for higher health consciousness in younger elderly. Risk factors for malnutrition in elderly (eg, poor dentition, problems swallowing, taste deterioration, reduced mobility, financial hardship) have a particular impact on fruit and vegetable intake. Increasing their consumption in the elderly population should therefore be promoted.

The Debate Goes on: New Evidence for the Role of Macronutrient Distribution on Body Weight Development

http://dx.doi.org/10.1016/j.ebiom.2017.09.018 2352-3964/© 2017 The Authors. Published by Elsevier B.V There has been an ongoing debate about the role of macronutrient carbohydrate diet (LF-HC, 20% of energy from fat, 66% from carbohycomposition of the diet in weight management and the potential of its modification as an approach to fight obesity. The importance of this question is obvious from the high and – in ever more parts of the World – still increasing prevalence of excessive body weight and the health impairments associated with it. Indeed, according to estimates from the World Health Organization (WHO), at the global level about 11% of men and 15% of women aged ≥18 years had a body mass index ≥ 30 kg/m in 2014 (World Health Organization, 2017). At the national level, prevalence is even higher in many countries also among developing and especially transition countries that are increasingly adopting a so-called Westernized food pattern. This latter is characterized by a large contribution of highly processed foods rich in simple carbohydrates in the form of sugar, and fat but poor in dietary fiber, micronutrients and secondary plant components that have been associated with beneficial health effects. A comparable trend is also observed in China. However, contrary to manyWestern countries where recent nutrition trends have seen a rise in simple carbohydrate intake at the expense of fat, the transition in China went in the opposite direction, from the traditional Chinese diet high in carbohydrate from rice and low in fat, to a nutrition with about twice the energy amount contributed by fat. This development was accompanied by a marked increase in overweight and obesity. This fact prompted a dietary intervention study investigating the effects of macronutrient composition on body weight and a number of metabolic health markers in 245 healthy Chinese adults (18–35 years) conducted at the Chinese Peoples Liberation Army General Hospital Beijing and the Department of Food Science and Nutrition at the Zhejiang University. Results from this study have recently been published by Wan et al. (2017) and provide interesting and convincing evidence for the benefits of moderation when it comes to fat intake. Participants were randomly assigned to one of three diets, a lower fat, higher