Regular Food Consumption Research Articles

Short-Term Long Chain Omega3 Diet Protects from Neuroinflammatory Processes and Memory Impairment in Aged Mice

Regular consumption of food enriched in omega3 polyunsaturated fatty acids (ω3 PUFAs) has been shown to reduce risk of cognitive decline in elderly, and possibly development of Alzheimer's disease. Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are the most likely active components of ω3-rich PUFAs diets in the brain. We therefore hypothesized that exposing mice to a DHA and EPA enriched diet may reduce neuroinflammation and protect against memory impairment in aged mice. For this purpose, mice were exposed to a control diet throughout life and were further submitted to a diet enriched in EPA and DHA during 2 additional months. Cytokine expression together with a thorough analysis of astrocytes morphology assessed by a 3D reconstruction was measured in the hippocampus of young (3-month-old) and aged (22-month-old) mice. In addition, the effects of EPA and DHA on spatial memory and associated Fos activation in the hippocampus were assessed. We showed that a 2-month EPA/DHA treatment increased these long-chain ω3 PUFAs in the brain, prevented cytokines expression and astrocytes morphology changes in the hippocampus and restored spatial memory deficits and Fos-associated activation in the hippocampus of aged mice. Collectively, these data indicated that diet-induced accumulation of EPA and DHA in the brain protects against neuroinflammation and cognitive impairment linked to aging, further reinforcing the idea that increased EPA and DHA intake may provide protection to the brain of aged subjects.

Can overeating induce conditioned taste avoidance in previously food restricted rats?

While feeding is rewarding, the feeling of satiation has been theorized to have a mixed affect. Using a food restriction model of overeating we examined whether bingeing was capable of supporting conditioned taste avoidance (CTA). Adult male Sprague–Dawley rats were maintained on either an ad lib ( n = 8) or restricted (50% of regular consumption; n = 24) food access for 20 days. On Days 9, 14, and 19 all rats were given access to a novel saccharin solution in place of water, and two groups of food restricted rats were given access to either 100% of regular food consumption or ad lib food. Ad lib access in the restricted rats induced significant overeating on all three exposures. After all rats were returned to ad lib feeding, a 24 h two-bottle saccharin/water choice test displayed significantly reduced saccharin consumption in the overeating rats, compared to those in the other 3 groups. To determine whether this avoidance was due to a learned association, a second experiment used a latent inhibition paradigm, familiarizing half the rats with the saccharin for 8 days prior to pairing it with overeating. Using the design of Experiment 1, with only the continuously ad lib and the restricted to ad lib feeding groups, it was found that the overeating-induced saccharin avoidance was attenuated by the pre-exposure. These results suggest that self-induced overeating is capable of supporting a learned avoidance of a novel solution suggestive of a conditioned satiety or taste avoidance.

Diet and acne: a review of the evidence

Pharmaceutical acne treatments are costly and have potentially severe side-effects. Adolescent acne is typically the result of clogged, infected, pilosebaceous follicles. Adults may experience fewer comedones and more inflammatory lesions. 1 Normally, sebum travels up the follicle to the skin surface. Hormones may increase sebum production and cause follicular cells to hyperproliferate and block the follicular opening, forming a comedo. 4 Complete follicle blockage results in closed comedones (i.e. “whiteheads”), whereas incomplete blockage results in open comedones (“blackheads”). Comedo formation typically occurs over the course of 2–3 weeks. Acne may manifest in the form of noninflammatory comedones, superficial inflammatory lesions (papules, pustules), and/or deeper inflammatory lesions (nodules, cysts). Inflammatory lesion formation occurs most commonly when Propionibacterium acnes colonizes the pilosebaceous unit, triggering follicular rupture and a neutrophil cascade. 5

Vascular action of polyphenols

Dietary patterns are widely recognised as contributors to cardiovascular and cerebrovascular disease. Endothelial function, the elastic properties of large arteries and the magnitude and timing of wave reflections are important determinants of cardiovascular performance. Several epidemiological studies suggest that the regular consumption of foods and beverages rich in flavonoids is associated with a reduction in the risk of several pathological conditions ranging from hypertension to coronary heart disease, stroke and dementia. The impairment of endothelial function is directly related to ageing and an association between decreased cerebral perfusion and dementia has been shown to exist. Cerebral blood flow (CBF) must be maintained to ensure a constant delivery of oxygen and glucose as well as the removal of waste products. Increasing blood flow is one potential way for improving brain function and the prospect for increasing CBF with dietary polyphenols is extremely promising. The major polyphenols shown to have some of these effects in humans are primarily from cocoa, wine, grape seed, berries, tea, tomatoes (polyphenolics and nonpolyphenolics), soy and pomegranate. There has been a significant paradigm shift in polyphenol research during the last decade. This review summarises our current knowledge in this area and points the way for the development of new types of functional foods targeted to brain health through improving vascular health.

Short-Term Consumption of a Dark Chocolate Containing Flavanols is Followed by a Significant Decrease in Normotensive Population

Cardiovascular disease (CVD) is the primary chronic disease afflicting industrialized societies today. Development of atherosclerosis, thrombosis and hypertension is a multifactorial process in which endothelial dysfunction, inflammatory response, modified lipids and lipoproteins and activated platelets all play significant roles in the process. Numerous epidemiologic studies support the concept that regular consumption of foods and beverages rich in antioxidant vitamins and flavonoids is associated with a decreased risk of CVD mortality, specially hypertension. Foods that have been identified as having a high polyphenolic flavonoid content include many fruits and vegetables such as apples and onions, teas (green and black), red wines and certain chocolates. The purpose of this paper is to determine changes in systolic and diastolic blood pressure due to the intake of calculated amount of dark and white chocolate and to investigate its effects on the anthropometric measures. Eighty nine females with mean age of 21.45±19.8 years (from 18-25 years) were included in this study. The studied populations were divided into three groups; group I included thirty females who received 100 gram of dark chocolate (Galaxy, containing .500 mg polyphenols) every day for fifteen days, group II included thirty females who received 90 gram of white chocolate (Galaxy, containing no polyphenols) every day for fifteen days and group III included twenty nine females who were prevented from any type of chocolate for fifteen days. Along our sample population, two blood pressure readings and several anthropometric measures were recorded. After fifteen days of ingestion of dark chocolate, there was statistically significant lowering in the systolic and diastolic blood pressure (p 0.05). As expected, the serum lipid concentrations were in the range of normality with no significant differences between groups (p>0.05). Current dietary studies indicate that short-term administration of dark chocolate (but not white chocolate) is followed by a significant decrease in blood pressure in healthy persons. These findings indicate that dark chocolate may exert a protective action on the vascular endothelium.

Grain fractionation technologies for cereal beta-glucan concentration

Mixed linkage beta-glucan is a cell wall component of cereal grains such as oat and barley. A number of nutritional studies have demonstrated a link between the regular consumption of foods containing cereal beta-glucan at physiologically effective concentrations and a reduced risk of chronic health problems. However, since beta-glucan exists in lower concentrations in grains, its incorporation into regular foods at physiologically effective levels without compromising the sensory attributes of foods has been a problem. Therefore, industry interest has been growing to produce beta-glucan concentrates. This article reviews the different types of dry and wet technologies available for concentration of cereal beta-glucan with a focus on commercial scale processing and their impact on the physicochemical properties of beta-glucan.

Potential for improvement of population diet through reformulation of commonly eaten foods

FOOD REFORMULATION: Reformulation of foods is considered one of the key options to achieve population nutrient goals. The compositions of many foods are modified to assist the consumer bring his or her daily diet more in line with dietary recommendations. INITIATIVES ON FOOD REFORMULATION: Over the past few years the number of reformulated foods introduced on the European market has increased enormously and it is expected that this trend will continue for the coming years. LIMITS TO FOOD REFORMULATION: Limitations to food reformulation in terms of choice of foods appropriate for reformulation and level of feasible reformulation relate mainly to consumer acceptance, safety aspects, technological challenges and food legislation. IMPACT ON KEY NUTRIENT INTAKE AND HEALTH: The potential impact of reformulated foods on key nutrient intake and health is obvious. Evaluation of the actual impact requires not only regular food consumption surveys, but also regular updates of the food composition table including the compositions of newly launched reformulated foods.

Effect of consumption of dark chocolate on lipoproteins and serum lipids

Background and aimEpidemiological studies suggest that regular consumption of foods and beverages rich in flavonoids is associated with a decreased risk of cardiovascular mortality. Cocoa, the main ingredient of chocolate, is rich in polyphenols. The aim of this study was to investigate the effects of consumption of 50 g daily for 3 weeks of flavonoid-rich dark chocolate on lipoprotein oxidative stress in vitro and in vivo. In particular, levels of thiobarbituric acid-reactive substances (TBARS), conjugated dienes, lipoperoxide and hydroperoxide in HDL and LDL before and after consumption of flavonoid-rich dark chocolate were assessed. The serum lipid profile was also studied.Methods and resultsTen healthy Italian-Caucasian volunteers were recruited without restriction as to age, gender, or socioeconomic status. Their BMI was between 21 and 26 kg/m2, and the subjects included men and premenopausal women. The study protocol was conducted in accordance with the principles of the Declaration of Helsinki as revised in 2001, and all subjects gave written informed consent. TBARs concentrations, lipid hydroperoxides as determined using the FOX assay, and conjugate formation in HDL and in LDL were significantly decreased after 3 weeks of dark chocolate consumption with respect to the baseline values. To summarize, the present study showed favourable effects of chocolate consumption both on HDL cholesterol, and on some of the lipid peroxidation markers such as conjugated dienes, lipid hydroperoxides (FOX assay) and TBARS. Similar results were obtained with regard to LDL fractions. Our study also showed that 3 weeks consumption of dark chocolate might improve endothelial function in healthy humans and might exert a protective effect on the cardiovascular system.

Impact of foods enriched withn-3 long-chain polyunsaturated fatty acids on erythrocyten-3 levels and cardiovascular risk factors

Consumption of fish or fish oils rich in the n-3 long chain PUFA EPA and DHA may improve multiple risk factors for CVD. The objective of this study was to determine whether regular consumption of foods enriched with n-3 long-chain PUFA can improve n-3 long-chain PUFA status (erythrocytes) and cardiovascular health. Overweight volunteers with high levels of triacylglycerols (TG; >1.6 mmol/l) were enrolled in a 6-month dietary intervention trial conducted in Adelaide (n 47) and Perth (n 39), and randomised to consume control foods or n-3-enriched foods to achieve an EPA + DHA intake of 1 g/d. Test foods were substituted for equivalent foods in their regular diet. Erythrocyte fatty acids, plasma TG and other CVD risk factors were monitored at 0, 3 and 6 months. There were no significant differences between groups for blood pressure, arterial compliance, glucose, insulin, lipids, C-reactive protein (CRP) or urinary 11-dehydro-thromboxane B2 (TXB2) over 6 months, even though regular consumption of n-3-enriched foods increased EPA + DHA intake from 0.2 to 1.0 g/d. However, the n-3 long-chain PUFA content of erythrocytes increased by 35 and 53 % at 3 and 6 months, respectively, in subjects consuming the n-3-enriched foods. These increases were positively associated with measures of arterial compliance and negatively associated with serum CRP and urinary 11-dehydro-TXB2 excretion. Sustainable increases in dietary intakes and erythrocyte levels of n-3 long-chain PUFA can be achieved through regular consumption of suitably enriched processed foods. Such increases may be associated with reduced CV risk.

Reproducibility and validity of a food frequency questionnaire

Methods to evaluate food consumption still need improvement. A study was conducted to verify the reproducibility and validity of a food frequency questionnaire (FFQ) among overweight adults. The study was carried out in a private university in São Paulo, Brazil. The study sample consisted of 146 individuals of both sex with body mass index =25 kg/m2 and age between 18 and 60 years old. For reproducibility the FFQ was applied by trained interviewers at two different instances with a mean interval time of 47 days. For validity, data collected from the FFQ were compared with those obtained from the average of 3 different daily records of a 24-hour dietary recall (mean interval time: 15 days). Validity and reproducibility of data on calories and macronutrients consumption was assessed using pondered kappa statistics and intraclass correlation coefficient. A higher variability in the reporting of regular food consumption was seen among obese than overweight individuals. Concerning reproducibility, kappa statistical values varied from 0.23 (carbohydrates and fats) to 0.40 (calories), and intraclass correlation coefficients ranged from 0.28 (protein) to 0.54 (total calories). For FFQ validity, the highest kappa value was 0.25 (calories), and the intraclass correlation coefficient was 0.21 (protein). Food consumption reports of overweight individuals tend to be underestimated. Despite its limitations, FFQ could be used in epidemiological studies to assess the regular food consumption of overweight individuals.

Incorporating Subsistence into Hedonic Price and Nutrient Demand Equations

The characteristics model of consumer choice is modified to accommodate subsistence. Implications of the model for evaluation of the hedonic price equations and nutrient demand equations are explored. The new model is tested using the 1977–1978 Nationwide Food Consumption Survey.

Lipids as excipient in sustained release insulin implants

When implanted in Wistar rats with streptozotocin-induced diabetes, the release of insulin from an admixture with cholesterol which had been compressed into a pellet disc was previously found to continue for about 30 days. Several common fatty acids, their anhydrides, and glycerides were evaluated for similar suitability as a component of the implant in this study. Stearic acid and palmitic acid were found to be very promising. Especially with palmitic acid, a 25 mg piece containing 20% insulin reduced hyperglycemia to 3.7 ± 0.8 mmol/1 for 43.5 ± 6.5 days when implanted subcutaneously in diabetic rats. The stable blood glucose leve followed a regular food consumption pattern. But under scheduled feeding, the level varied from 2.4 ± 0.3 to 6.2 ± 0.5 mmol/1. However, hypoglycemic convulsion did not occur even after fasting for 16 h. Therefore, the rat model study indicates that palmitic acid can be a useful adjunct in sustaining the release of insulin from an implant.