Rye bread intake improves oxidation resistance of LDL in healthy humans

Causal relationships between dietary habits and Barrett's esophagus risk: a univariable and multivariable Mendelian randomization study

Aims: Dietary habits are reported to be associated with Barrett's esophagus (BE) risk; however, whether there is a causal relationship remains controversial. Here, we systematically examined the causal effects of genetically predicted dietary habits on BE risk through a Mendelian randomization (MR) analysis approach. Methods: Data for exposures were obtained from the UK Biobank (UKB), while the summary-level data for outcomes were obtained from a large sample-size GWAS meta-analysis. Genetic variants associated with 17 ordinary dietary habits at the genome-wide significance level were regarded as instrumental variables (IVs). Univariable and multivariable MR analyses were conducted to explore the causal relationships between dietary habits and BE risk. Sensitivity analyses were implemented to evaluate robustness of the results and determine the potential pleiotropy bias. Results: Univariable MR (UVMR) analysis showed that genetic predisposition to alcohol intake frequency, cooked vegetable intake, beef intake, bread intake, fresh fruit intake, salad/raw vegetable intake, and dried fruit intake were associated with BE risk, with all P values <0.05. After adjusting confounders, the effects of four dietary habits on BE risk persisted; multivariable MR (MVMR) analysis revealed that alcohol intake frequency (adjusted odds ratio (OR) = 1.74 (1.34, 2.27); P = 3.42 × 10-5) was causally associated with higher BE risk, the cooked vegetable intake (adjusted OR = 2.64 (1.16, 5.97); P = 0.02) had suggestively increased BE risk, while higher consumption of bread (adjusted OR = 0.54 (0.32-0.91); P = 0.02) and fresh fruit (adjusted OR = 0.34 (0.15, 0.77); P = 0.01) were suggestively associated with lower BE risk. Conclusions: These MR analyses demonstrate evidence of causal relationships between dietary habits and BE risk. These findings provide new insights into targeted dietary intervention strategies for BE prevention.

A Review of Foods of Plant Origin as Sources of Vitamins with Proven Activity in Oxidative Stress Prevention according to EFSA Scientific Evidence

Beyond their nutritional benefits, vitamins could decrease the risk of chronic diseases due to their potent antioxidant capacity. The present work is aimed at reviewing the state of the art regarding (1) the vitamins involved in oxidative stress prevention in accordance with the requirements established by the European Food Safety Authority (EFSA) and (2) the foods of plant origin that are sources of those vitamins and have potential benefits against oxidative stress in humans. According to the European regulations based on EFSA scientific evidence, riboflavin, vitamin C, and vitamin E are those vitamins subjected to the approved health claim "contribute to the protection of cells from oxidative stress". Scientific studies conducted in humans with some natural food sources of riboflavin (almonds, wheat germ, mushrooms, oat bran), vitamin C (guava, kale, black currant, Brussels sprouts, broccoli, orange), and vitamin E (hazelnuts, almonds, peanuts, pistachio nuts, extra virgin olive oil, dates, rye) have been performed and published in the literature. However, no food of plant origin has obtained a favorable EFSA opinion to substantiate the approval of health claims related to its potential properties related to oxidative stress prevention. Further studies (concretely, well-controlled human intervention studies) must be carried out in accordance with EFSA requirements to provide the highest level of scientific evidence that could demonstrate the potential relationship between foods of plant origin and antioxidant capacity. This review could be useful for the scientific community to study the application of health claims referring to the antioxidant capacity potentially exerted by foods of plant origin.

Functional, Nutritional, and Sensory Quality of Mixed Flours-Based Breads as Compared to Durum Wheat Semolina-Based Breads

Increasing preference of consumers and bakers towards bread manufactured with mixed flours and/or sourdough drove us to investigate about influence of flours and sourdough on crumb grain, chemical, sensory, and in vitro glycaemic index (GI) and antioxidant activity of bread. To this aim, we produced and compared six experimental breads: three were based on a mixture of flours (soft wheat, durum wheat semolina, barley, oat, rye, and buckwheat); three were semolina-based breads. Two different sourdoughs (wheat or mixed flours) were assessed. Compared to semolina breads, those containing a mixture of flours showed higher specific volume. The use of sourdough led to increased concentrations of total free amino acids (FAA). Mixed flours bread with addition of mixed flours sourdough was rich in some essential FAA and amino acid derivative bioactive gamma-aminobutyric acid. Type of flours had higher influence than sourdough addition on volatile organic compounds. All the mixed flours breads, although showing profiles of volatile organic compounds differing from those of semolina breads, resulted acceptable. In addition, they had lower GI and higher antioxidant activity than semolina breads. Type of flours had much higher impact on GI and antioxidant activity than sourdough.

Protection of natural antioxidants against low-density lipoprotein oxidation

This chapter reports essential information about the protective action of antioxidants against LDL oxidation. The activity of individual compounds (tocopherols, vitamin C, phenolic compounds) as well as extracts obtained from plant material (cereals, fruits, legumes, nuts, mushrooms, by-products of food industry) is reported. The structure-antioxidant activity relationship of phenolic compounds is discussed. This article summarizes the findings to date of both in vitro and in vivo studies using foods or phenolic extracts isolated from foodstuffs at inhibiting the incidence of LDL oxidation. This chapter summarizes also the reportings to date of in vivo studies using foods or beverages at inhibiting the incidence of LDL oxidation.

Biomarkers of cereal food intake

Background/objectives

Cereal foods are major contributors to the daily energy, protein, and dietary fiber intake all over the world. The role of cereals in human health is dependent on whether they are consumed as refined or whole grain and on cereal species. To unravel the underlying mechanisms of health effects attributed to specific cereal foods and to provide more precise dietary advice, there is a need for improved dietary assessment of whole-grain intake. Dietary biomarkers of specific cereals, different fractions or cereal-containing foods could offer such a possibility. The aim of this review was to summarize the current status on biomarkers of different cereals, fractions, and specific cereal foods.

Subjects and methods

A literature review was conducted and putative biomarkers of different cereals and pseudo-cereals (wheat, oats, rye, barley, rice, and quinoa) as well as for different grain fractions (whole grain, refined grain, bran) and foods were summarized and discussed.

Results

Several putative biomarkers have been suggested for different cereals, due to their unique presence in these grains. Among the biomarkers, odd-numbered alkylresorcinols are the most well-studied and -evaluated biomarkers and reflect whole-grain wheat and rye intake. Even-numbered alkylresorcinols have been suggested to reflect quinoa intake. Recent studies have also highlighted the potential of avenanthramides and avenacosides as specific biomarkers of oat intake, and a set of biomarkers have been suggested to reflect rice bran intake. However, there are yet no specific biomarkers of refined grains. Most biomarker candidates remain to be evaluated in controlled interventions and free-living populations before applied as biomarkers of intake in food and health studies.

Conclusion

Several putative biomarkers of different cereals have been suggested and should be validated in human studies using recently developed food intake biomarker validation criteria.

The Potential Protective Effects of Phenolic Compounds against Low-density Lipoprotein Oxidation

BACKGROUND

The exact mechanism(s) of atherosclerosis in humans remains elusive, but one theory hypothesizes that this deleterious process results from the oxidative modification of low-density lipoprotein (LDL). Research suggests that foods rich in dietary phenolic compounds with antioxidant activity can mitigate the extent of LDL oxidation in vivo. With regard to the different classes of flavonoids, there appears to be a structurefunction relationship between the various moieties/constituents attached to the flavonoids' three ring system and their impact at retarding LDL oxidation.

METHODS

This article summarizes the findings to date of both in vitro and in vivo studies using foods or phenolic extracts isolated from foodstuffs at inhibiting the incidence of LDL oxidation. Three bases: SCOPUS, Web Science, and PubMed were used for search.

RESULTS

An often used method for the determination of antioxidant properties of natural phenolic compounds is the LDL oxidation assay. LDLs are isolated from human plasma and their oxidation is induced by Cu2+ ions or 2,2'-azobis(2-methylpropionamidine) dihydrochloride (AAPH). The sample is incubated with a phenolic extract or individual/isolated phenolic compounds. LDL oxidation is then monitored by various chemical methods (e.g., measurement of the generation of conjugated dienes and trienes). This technique confirmed the antioxidant properties of several extracts as obtained from plant material (e.g., grapes, berries, orange, grapefruit, coffee, tea, chocolate, olives, nuts) as well as the individual phenolic compounds (e.g., luteolinidin, apigenidin, caffeic acid, chlorogenic acid, catechin, quercetin, rutin). Several studies in vivo confirmed protective effects of phenolic compounds against LDL oxidation. They covered the healthy subjects with hyperlipidaemia, overweight, obesity, metabolic syndrome, heavy smokers, patients receiving haemodialysis, patients with peripheral vascular disease, and subjects at high cardiovascular risk. The studies comprise individuals of all ages, and the number of participants in the different experiments varied widely.

CONCLUSION

Properly designed double-blind, placebo-controlled randomised clinical trials offer stronger evidence as to the impact of dietary phenolics consumption at retarding LDL oxidation. More such clinical trials are needed to strengthen the hypothesis that foods rich in dietary phenolic compounds with antioxidant activity can mitigate the extent of LDL oxidation in vivo.

Antioxidant properties of diverse cereal grains: A review on in vitro and in vivo studies

Cereal grains and products have gained popularity in contributing to healthy eating behavior because of their antioxidant properties associated with protection against chronic diseases. In this review, notable studies on the in vitro and in vivo antioxidant activity of commonly consumed cereal grains are summarized. Cereals contain phytochemicals or certain minor components with antioxidant properties. The antioxidant potential of cereals depends on their bioaccessibility, absorption in the gastrointestinal and their bioavailability utilization in vivo. The in vitro gastrointestinal digestion and fermentation of cereals increased their antioxidant potentials which are significantly correlated with their total phenolic contents. Most studies performed in vivo have been concerned with the antioxidant properties of colored rice, wheat bran and rye products. There are inadequate in vitro and in vivo studies on antioxidative potentials of fermented versus unfermented cereals. Therefore, further studies are necessary to maximize possible health benefits of cereal antioxidative phytochemicals.

Effects of consumption of whole grain foods rich in lignans in healthy postmenopausal women with moderate serum cholesterol: a pilot study

This study aims at investigating the effect of an experimental period of intake of whole grain foods rich in lignans as part of an habitual diet on the plasma and urinary excretion of enterolignans, the biomarkers of lipid metabolism and the immunological and antioxidant status in a group of postmenopausal women with moderate serum cholesterol. A randomized double-blind crossover study was completed on 13 subjects in 12-weeks after protocol approval of an ethical committee. The subjects consumed whole grain foods high in lignans (30 g/d of breakfast cereals or biscuits, etc., 80 g/d of whole grain pasta) or refined grain foods for 4 weeks, separated by a 2-weeks wash-out period. A modest hypocholesterolemic effect (p < 0.05) of the whole grain diet was observed and the intake of whole grain products rich in lignans was also associated with an increase in urinary enterodiol excretion (p < 0.05).