Anterior cingulate taste activation predicts ad libitum intake of sweet and savory drinks in healthy, normal-weight men

After food consumption, the motivation to eat (wanting) decreases and associated brain reward responses change. Wanting-related brain responses and how these are affected by consumption of specific foods are ill documented. Moreover, the predictive value of food-induced brain responses for subsequent consumption has not been assessed. We aimed to determine the effects of consumption of sweet and savory foods on taste activation in the brain and to assess how far taste activation can predict subsequent ad libitum intake. Fifteen healthy men (age: 27 ± 2 y, BMI: 22.0 ± 1.5 kg/m2) participated in a randomized crossover trial. After a >3-h fast, participants were scanned with the use of functional MRI before and after consumption of a sweet or savory preload (0.35 L fruit or tomato juice) on two occasions. After the scans, the preload juice was consumed ad libitum. During scanning, participants tasted the juices and rated their pleasantness. Striatal taste activation decreased after juice consumption, independent of pleasantness. Sweet and savory taste activation were not differentially affected by consumption. Anterior cingulate taste activation predicted subsequent ad libitum intake of sweet (r = -0.78; P < 0.001(uncorrected)) as well as savory juice (r = -0.70; P < 0.001(uncorrected)). In conclusion, we showed how taste activation of brain reward areas changes following food consumption. These changes may be associated with the food's physiological relevance. Further, the results suggest that anterior cingulate taste activation reflects food-specific satiety. This extends our understanding of the representation of food specific-appetite in the brain and shows that neuroimaging may provide objective and more accurate measures of food motivation than self-report measures.     

Susceptibility to overeating affects the impact of savory or sweet drinks on satiation, reward, and food intake in nonobese women

Taste is involved in food preference and choice, and it is thought that it can modulate appetite and food intake. The present study investigated the effect of savory or sweet taste on satiation, reward, and food intake and according to individual differences in eating behavior traits underlying susceptibility to overeating. In a crossover design, 30 women (BMI = 22.7 ± 2.3; age = 21.9 ± 2.6 y) consumed a fixed energy preload (360 kJ/g) with a savory, sweet, or bland taste before selecting and consuming items from a test meal ad libitum. Sensations of hunger were used to calculate the satiating efficiency of the preloads. A computerized task was used to examine effects on food reward (explicit liking and implicit wanting). The Three Factor Eating Questionnaire was used to compare individual differences in eating behavior traits. Satiation and total food intake did not differ according to preload taste, but there was an effect on explicit liking and food selection. The savory preload reduced liking and intake of high-fat savory foods compared to sweet or bland preloads. The eating behavior trait disinhibition interacted with preload taste to determine test meal intake. Higher scores were associated with increased food intake after the sweet preload compared to the savory preload. Independent of preload taste, disinhibition was associated with lower satiating efficiency of the preloads and enhanced implicit wanting for high-fat sweet food. Savory taste has a stronger modulating effect on food preference than sweet or bland taste and may help to preserve normal appetite regulation in people who are susceptible to overeating.     

Nothing beats taste or convenience: a national survey of where and why people buy sugary drinks in Australia

Objective : There is limited knowledge of what influences sugary drink purchasing decisions in the Australian population. This study aimed to identify the most common locations and reasons across different demographic groups for purchasing sugary drinks in Australia. Methods : A total of 891 respondents (who purchased sugary drinks for personal consumption at least occasionally) from a broader national population telephone survey of Australian adults conducted in 2017 (n=3,430) were included in the analysis. Results : ‘Taste’ was a ubiquitous reason for purchase (94%) and the majority also agreed with ‘easily available’ (76%). Males, younger people and people of lower socioeconomic status (SES) were significantly more likely to agree that sugary drinks were ‘cheap’ and ‘better value than water’. Furthermore, males and younger people were more likely to report buying sugary drinks because they were ‘part of a meal deal’. The most common purchase locations were supermarkets (56%), followed by convenience stores (19%) and food or entertainment venues (17%). Conclusion : Taste is paramount in decisions to purchase sugary drinks, and widespread availability and value for money support consumption. Implications for public health : Policies and interventions targeting point‐of‐sale sugary drink purchasing decisions among the most ‘at risk’ consumers are warranted.     

Functional magnetic resonance imaging of human hypothalamic responses to sweet taste and calories

BACKGROUND: Evidence exists that beverages do not trigger appropriate anticipatory physiologic responses, such as cephalic phase insulin release. Therefore, it is of interest to elucidate the food properties necessary for triggering adaptive responses. Previously, we found a prolonged dose-dependent decrease in the hypothalamic functional magnetic resonance imaging signal after ingestion of a glucose solution. OBJECTIVES: The aims of the present study were to measure the effects of sweet taste and energy content on the hypothalamic response to glucose ingestion and to measure the concomitant changes in blood glucose and insulin concentrations. DESIGN: Five healthy, normal-weight men participated in a randomized crossover design trial. The subjects were scanned 4 times for 37 min on separate days with functional magnetic resonance imaging. After 7 min, they ingested 1 of the following 4 stimuli (300 mL of each): water (control), a glucose solution, an aspartame (sweet taste) solution, or a maltodextrin (nonsweet carbohydrate) solution. RESULTS: Glucose ingestion resulted in a prolonged and significant signal decrease in the upper hypothalamus (P < 0.05). Water, aspartame, and maltodextrin had no such effect. Glucose and maltodextrin ingestions resulted in similar increases in blood glucose and insulin concentrations. However, only glucose triggered an early rise in insulin concentrations. Aspartame did not trigger any insulin response. CONCLUSIONS: Our findings suggest that both sweet taste and energy content are required for a hypothalamic response. The combination of sweet taste and energy content could be crucial in triggering adaptive responses to sweetened beverages.     

Plasma concentration response to drinks containing beta-carotene as carrot juice or formulated as a water dispersible powder

Summary. Background: Bioavailability of β-carotene is highly variable and depends on the source, the formulation and other nutritional factors. Objective: It was the aim of the study to compare β-carotene plasma response to b-carotene dosing with two commercially available drinks, containing β-carotene from carrot juice or as water dispersible β-carotene powder. Design In a randomized, parallel group study design, 4 volunteers per group received daily β-carotene doses of 6–7 or 18–22 mg of either drink over 6 weeks. Blood samples for determination of carotenoid and vitamin A plasma concentrations were collected before supplementation and over the dosing period. Results: Apparent steady-state β-carotene concentrations were attained after 40 days of supplementation. Consumption of the beverage containing β-carotene as a water dispersible powder resulted in a higher response of β-carotene plasma concentrations with increments of 3.84 ± 0.60 μmol/L (p < 0.05, dose: 7.2 mg/d) and 5.04 ± 0.72 μmol/L (p < 0.05, dose: 21.6 mg/d), respectively, in comparison to the carrot juice-based drink with increments of 0.42 ± 0.33 μmol/L (dose: 6 mg/d) and 1.71 ± 0.55 μmol/L (dose: 18 mg/d), respectively. β-carotene was cleared from the plasma with an apparent half-life of 6–11 days. Plasma concentrations of α-carotene, β-cryptoxanthin, lutein, zeaxanthin, and lycopene remained almost unchanged, whereas retinol plasma concentrations increased slightly. By contrast, with the exception of elevated 13-cis-retinoic acid in one group (21.6 mg/d, water dispersible powder), the concentrations of all-trans-retinoic acid, and the oxo-derivatives or retinoic acid were not significantly affected by b-carotene supplementation. Conclusions: The results confirm that the relative bioavailability of β-carotene depends largely on the source of b-carotene and demonstrate the superior bioavailability of β-carotene powder in comparison to that in carrot juice. Received: 7 May 2002, Accepted: 22 August 2002 This work was supported by a grant from F. Hoffmann-La Roche Ltd., Vitamins and Nutrition Research, Basle, Switzerland. Correspondence to: Prof. Dr. med. Petra A. Thürmann     

Cardiovascular responses to sugary drinks in humans: galactose presents milder cardiac effects than glucose or fructose

Purpose

There is increasing interest into the potentially beneficial effects of galactose for obesity and type 2 diabetes management as it is a low-glycemic sugar reported to increase satiety and fat mobilization. However, fructose is also a low-glycemic sugar but with greater blood pressure elevation effects than after glucose ingestion. Therefore, we investigated here the extent to which the ingestion of galactose, compared to glucose and fructose, impacts upon haemodynamics and blood pressure.

Methods

In a randomized cross-over study design, 9 overnight-fasted young men attended 3 separate morning sessions during which continuous cardiovascular monitoring was performed at rest for at least 30 min before and 120 min after ingestion of 500 mL of water containing 60 g of either glucose, fructose or galactose. These measurements included beat-to-beat systolic and diastolic blood pressure, heart rate deduced by electrocardiography, and stroke volume derived by impedance cardiography; these measurements were used to calculate cardiac output and total peripheral resistance.

Results

Ingestion of galactose, like glucose, led to significantly lesser increases in systolic, diastolic and mean blood pressure than fructose ingestion (p < 0.05). Furthermore, the increase in cardiac output and reduction in total peripheral resistance observed after ingestion of glucose were markedly lower after galactose ingestion (p < 0.01).

Conclusions

Galactose thus presents the interesting characteristics of a low-glycemic sugar with mild cardiovascular effects. Further studies are warranted to confirm the clinical relevance of the milder cardiovascular effects of galactose than other sugars for insulin resistant obese and/or diabetic patients with cardiac insufficiency.

     

A large-scale intervention to introduce orange sweet potato in rural Mozambique increases vitamin A intakes among children and women

β-Carotene-rich orange sweet potato (OSP) has been shown to improve vitamin A status of infants and young children in controlled efficacy trials and in a small-scale effectiveness study with intensive exposure to project inputs. However, the potential of this important food crop to reduce the risk of vitamin A deficiency in deficient populations will depend on the ability to distribute OSP vines and promote its household production and consumption on a large scale. In rural Mozambique, we conducted a randomised, controlled effectiveness study of a large-scale intervention to promote household-level OSP production and consumption using integrated agricultural, demand creation/behaviour change and marketing components. The following two intervention models were compared: a low-intensity (1 year) and a high-intensity (nearly 3 years) training model. The primary nutrition outcomes were OSP and vitamin A intakes by children 6-35 months and 3-5·5 years of age, and women. The intervention resulted in significant net increases in OSP intakes (model 1: 46, 48 and 97 g/d) and vitamin A intakes (model 1: 263, 254 and 492 μg retinol activity equivalents/d) among the younger children, older children and women, respectively. OSP accounted for 47-60 % of all sweet potato consumed and, among reference children, provided 80 % of total vitamin A intakes. A similar magnitude of impact was observed for both models, suggesting that group-level trainings in nutrition and agriculture could be limited to the first project year without compromising impact. Introduction of OSP to rural, sweet potato-producing communities in Mozambique is an effective way to improve vitamin A intakes.     

Habitual plate-waste of 6- to 9-year-olds may not be associated with lower nutritional needs or taste acuity,but undesirable dietary factors

Efforts to reduce plate-waste (PW) are limited to those by a dietitian who serves the entire school rather than a better characterization of individuals who are served. We tested the hypothesis that children reporting habitual PW would have different physical or dietary characteristics compared with children without PW. Participants were 407 children aged 6 to 9 years in elementary schools in Kyeonggi, Korea. Information on eating behavior and food preference was collected using a questionnaire administered by parents. Among them, 91 students participated further in anthropometry, step counting, taste acuity tests, and nutrition intake from school lunches. Participants were divided into tertiles according to total frequency of leaving PW from each meal on a typical day: no PW, moderate PW, and habitual PW. Children with habitual PW showed several undesirable characteristics: consuming less of various vegetables, eating only what they like, poor table manners, and frequent consumption of street foods and cookies/beverages/fast foods. Whereas height, weight, and obesity index as well as taste acuity and daily steps in the habitual PW group were not significantly different, intakes of potassium, niacin, and folate were significantly lower compared with the other groups. Therefore, habitual PW did not seem to result from having a lower energy requirement or different taste acuity, or result in observed slowed growth, but it could place children at a risk for insufficient nutritional intake, consequently impairing growth and general health. The results emphasize the parental role in shaping children's diet and provide information for developing strategies to reduce PW of individual children.     

The addition of milk or yogurt to a plant-based diet increases zinc bioavailability but does not affect iron bioavailability in women

The addition of milk and milk-based products to the diets of individuals subsisting on plant-based diets was reported to have positive effects on nutritional status and functional outcomes such as growth, morbidity, and cognition. We examined the effect of the addition of milk or yogurt on the bioavailability of zinc and iron from a plant-based rural diet. The subjects were 48 Mexican women (30.9 +/- 5.7 y) who habitually consumed a plant-based diet. The women were assigned to 1 of 3 groups: 1) the typical rural Mexican diet, 2) that diet with milk added, or 3) that diet with yogurt for 13 d. Zinc absorption was measured after extrinsically labeling meals with (67)Zn and an i.v. dose of (70)Zn; iron absorption was measured by extrinsically labeling meals with (58)Fe and a reference oral dose of (57)Fe. Including milk and yogurt in the diet increased zinc absorption by 50 and 68%, respectively (P < 0.05). The 3 groups did not differ in the percentage iron absorption. The total amount of zinc absorbed was increased (P < 0.05) by 70% when milk was added to the meal and 78% when yogurt was added. The total amount of iron absorbed did not differ among the groups. The addition of milk and yogurt to a plant-based diet high in phytate increases zinc bioavailability without affecting iron bioavailability.     

Simultaneous immunization with DNA and protein vaccines against Japanese encephalitis or dengue synergistically increases their own abilities to induce neutralizing antibody in mice

Gene-based and protein-based vaccines are two distinct types of vaccines. In this report, we examined if combined use of DNA and protein vaccines would increase their own abilities to induce neutralizing antibody in murine models for Japanese encephalitis (JE) or dengue type 2 (DEN2). DNA vaccines for JE (pcJEME) or DEN2 (pcD2ME) were inoculated intramuscularly, and protein vaccines consisting of subviral extracellular particles (EPs) containing JE (JEEP) or DEN2 (D2EP) virus antigens were inoculated subcutaneously with Freund's adjuvant. Two immunizations of ICR mice with pcJEME and/or JEEP in the prime-boost protocol indicated that levels of neutralizing antibody induced by the pcJEME prime-JEEP boost vaccination were two to eight-fold higher than those induced by pcJEME alone, but were equivalent to those induced by JEEP alone and slightly higher than those induced by the JEEP prime-pcJEME boost regimen. On the other hand, simultaneous immunization of ICR mice with pcJEME and JEEP provided synergistically higher neutralizing antibody titers than those provided by immunization with either immunogen. Immunization with graded doses of pcJEME and JEEP confirmed the synergism. The synergistic increase in neutralizing antibody titer by simultaneous immunization with DNA and protein vaccines was also shown by immunization with pcD2ME and D2EP in ICR and ddY mice. Both IgG1 and IgG2a antibodies were induced by combined immunization with pcJEME and JEEP.     

Interleukin-21 administration to rhesus macaques chronically infected with simian immunodeficiency virus increases cytotoxic effector molecules in T cells and NK cells and enhances B cell function without increasing immune activation or viral replication

We have previously shown that interleukin-21, a pleiotropic C γ-chain signaling cytokine, induces the expression of the cytotoxic molecules granzyme B (GrB) and perforin in vitro in CD8 T cells and NK cells of chronically HIV infected individuals. In this pilot study, four chronically SIV infected rhesus macaques (RM) in late-stage disease were given two doses of recombinant MamuIL-21, 50 μg/kg, intravenously 7 days apart, followed by one subcutaneous dose, 100 μg/kg, 23 days after the second dose. Three animals served as controls. After each dose of IL-21, increases were noted in frequency and mean fluorescence intensity of GrB and perforin expression in memory and effector subsets of CD8 T cells in peripheral blood (PB), in peripheral and mesenteric lymph node (LN) cells, in PB memory and effector CD4 T cells and in NK cells. Frequencies of SIV-gag specific CD107a⁺IFN-γ⁺ CD8 T cells increased 3.8-fold in PB and 1.8-fold in LN. In addition, PB CD27⁺ memory B cells were 2-fold higher and serum SIV antibodies increased significantly after IL-21 administration. No changes were observed in markers of T cell activation, T cell proliferation or plasma virus load. Thus, administration of IL-21 to chronically SIV infected viremic animals was safe, well tolerated and could augment the cytotoxic potential of T cells and NK cells, promote B cell differentiation with increases in SIV antibody titers without discernable increase in cellular activation. Further studies are warranted to elucidate the effects and potential benefit of IL-21 administration in the context of SIV/HIV infection and in SIV/HIV vaccine design.