Relationship of endogenous plasma concentrations of ß-hydroxy ß-methyl butyrate (HMB) with frailty in community dwelling older adults with type-2 diabetes mellitus.

BACKGROUND: Supplementation with ß-hydroxy ß-methyl butyrate (HMB) appears to be effective in preserving muscle in older adults. However, the association between endogenously produced HMB with frailty has not been studied in people with chronic disease. OBJECTIVES: The purpose of this study is to explore whether an association exists between endogenous HMB levels and frailty status in older adults with type-2 diabetes mellitus (T2DM). METHODS: Data were taken from the Toledo Study of Healthy Ageing, a community-dwelling aged (65 years+) cohort. Frailty was assessed at baseline and at 2.99 median years according to the Frailty Phenotype (FP) standardized to our population and the Frailty Trait Scale 12 (FTS12). The associations between HMB levels and frailty were assessed using three nested multivariate logistic regressions and segmented by sex. Glucose, HMB and glucose interaction, age and body composition were used as covariables. RESULTS: 255 participants (mean age 75.3 years, 52.94% men) were included. HMB levels showed an inverse cross-sectional association with frailty, which was modified when the interaction term HMB*glucose was included, remaining significant only for FTS12 [OR (95% CI): 0.436 (0.253, 0.751), p-value 0.003]. The association between HMB endogenous levels and FTS12 appears to be independent of sex, in which the association was maintained after adjusting for the covariates. However, there appears to be threshold points for glucose levels, above which the protective effect of HMB is lost: 145.4 mg/dl adjusted by gender for the whole sample and 149.6 mg/dl and 138.9 mg/dl for men and women, respectively. Endogenous HMB levels were not found to be associated with incident frailty. CONCLUSIONS: Cross-sectional analysis revealed that endogenous HMB levels were inversely associated with frailty as assessed by the FTS12 in older people with T2DM. This association was found to be dependent on circulating fasted glucose levels.

Association between endogenous plasma beta-hydroxy-beta-methylbutyrate levels and frailty in community-dwelling older people.

BACKGROUND: Frailty is a key element in healthy ageing in which muscle performance plays a main role. Beta-hydroxy-beta-methylbutyrate (HMB) supplementation has shown favourable effects in modulating protein synthesis, improving muscle mass and function in interventional studies. Decreased age-related endogenous HMB levels have been shown in previous studies. The aim of the present study is to assess whether there is an association between endogenous plasma HMB levels and frailty. METHODS: Data from 1290 subjects (56.98% women; mean ± standard deviation age 74.6 ± 5.95 years) from the Toledo Study for Healthy Aging were obtained. Participants had their frailty status qualified according to Fried's Frailty Phenotype (FFP) score and the Frailty Trait Scale in its 12-domain version (FTS-12). Plasma HMB levels were analysed by an ultrahigh-performance liquid chromatography tandem mass spectrometry. Differences between groups (frail vs. non-frail) were tested using Mann-Whitney U test, Kruskal-Wallis test and chi-squared test. The association between HMB and frailty was assessed by multivariate linear and logistic regressions when frailty was analysed as continuous and binary, respectively. Models were adjusted by age, gender, comorbidity, body composition and protein intake. RESULTS: HMB levels were lower in those aged ≥75 years than in those aged 65-74 years, with an inverse linear relationship between age and HMB levels (ß = -0.031; P = 0.018), mainly accounted by males (ß = -0.062; P = 0.002). HMB levels were higher in men (0.238 ± 0.065 vs. 0.193 ± 0.051 ng/mL; P ≤ 0.001). HMB levels were significantly lower in frail than in non-frail individuals: 0.204 ± 0.058 versus 0.217 ± 0.063 ng/dL (P = 0.001) according to the FFP and 0.203 ± 0.059 versus 0.219 ± 0.063 ng/mL (P < 0.001) according to FTS-12. These differences showed a dose-dependent profile when we compared them by quintiles of HMB (P for trend: 0.022; 0.012 and 0.0004, respectively, for FFP, FTS-12 binary and FTS-12 continuous). Variables associated with low HMB levels were body mass index, strength, exhaustion and weight loss. Frailty was associated with HMB levels in all the adjusted models, including the fully adjusted ones, no matter the tool used (odds ratio: 0.45 [0.26, 0.77] for FFP and 0.36 [0.20, 0.63] for FTS-12 binary; ß = -4.76 [-7.29, -2.23] for FTS-12 score). This association was also observed when the analyses were done by quintiles, showing such association since Q4 (FFP), Q2 (FTS-12 binary) and Q3 (FTS-12 score). The associations were observed in the whole sample and in each gender. CONCLUSIONS: There is an inverse association between HMB levels and frailty status. These findings support the design of targeted clinical trials to evaluate the effect of HMB supplementation in older frail people with low HMB levels.

A randomized controlled non-inferiority trial of primary care-based facilitated access to an alcohol reduction website (EFAR Spain).

BACKGROUND: Brief interventions (BI) for risky drinkers in primary healthcare have been demonstrated to be cost-effective but they are still poorly implemented. Digital BI seems to be a complementary strategy to overcome some barriers to implementation but there is a scarcity of studies in clinical environments. We present the results of a randomized controlled non-inferiority trial which tests the non-inferiority of facilitated access to a digital intervention (experimental condition) for risky drinkers against a face-to-face BI (control condition) provided by primary healthcare professionals. METHOD: In a non-inferiority randomized controlled trial, unselected primary healthcare patients (≥ 18 years old) were given a brief introduction and asked to log on to the study website to fill in the 3-item version of the Alcohol Use Disorders Identification Test. Positively screened patients (4+ for women and 5+ for men) received further online assessment (AUDIT, socio-demographic characteristics and EQ-5D-5L) and were automatically randomized to either face-to-face or digital BI (1:1). The primary outcome was the proportion of patients classified as risky drinkers by the digitally administered AUDIT at month 3. A multiple imputation approach for the missing data was performed. RESULTS: Of the 4499 patients approached by 115 healthcare professionals, 1521 completed the AUDIT-C. Of the 368 positively screened patients, 320 agreed to participate and were randomized to either intervention. At month 3, there were more risky drinkers in the experimental group (59.8%) than in the control group (52%), which was similar to the distribution at baseline and less than the pre-specified margin of 10%. The difference was not significant when accounting for possible confounders. CONCLUSION: Digital BI was not inferior to face-to-face BI, in line with previous findings and the a priori hypothesis. However, the low power of the final sample, due to the low recruitment and loss to follow-up, limits the interpretation of the findings. New approaches in this field are required to ensure the effective implementation of digital interventions in actual practice.

Oligomeric Formulas in Surgery: A Delphi and Consensus Study.

Nutritional management of patients with intestinal failure often includes the use of oligomeric formulas. Implementing the use of oligomeric formulas in surgical patients with maldigestion or malabsorption could be a nutritional strategy to be included in clinical protocols. We aim to generate knowledge from a survey focused on the effectiveness of nutritional therapy with oligomeric formulas with Delphi methodology. Each statement that reached an agreement consensus among participants was defined as a median consensus score ≥7 and as an interquartile range ≤3. The use of oligomeric formulas in surgical patients, starting enteral nutrition in the post-operative phase in short bowel syndrome and in nonspecific diarrhea after surgical procedures, could improve nutritional therapy implementation. Stakeholders agreed that early jejunal enteral nutrition with oligomeric formula is more effective compared to intravenous fluid therapy and it is useful in patients undergoing upper gastro-intestinal tract major surgery when malabsorption or maldigestion is suspected. Finally, oligomeric formulas may be useful when a feeding tube is placed distally to the duodenum. This study shows a practical approach to the use of oligomeric formulas in surgical patients with intestinal disorders and malabsorption, and it helps clinicians in the decision-making process.

Factors affecting engagement of primary health care professionals and their patients in facilitated access to online alcohol screening and brief intervention.

OBJECTIVE: Understanding the impact of Level of Information and Communication Technology Use, computer self-efficacy and perceived product usability of healthcare professionals regarding an alcohol consumption reduction website on facilitated access defined as referring patients to the webpage. METHODS: 52 nurses and 41 general practitioners were assessed before patient recruitment started, using a questionnaire designed to assess socio-demographic characteristics, professional engagement to the website, Level of Information and Communication Technology Use, Computer self-efficacy ("the judgment of one's capability to use a computer") and Perceived product usability ("the extent to which a product can be used by specified users to achieve specified goals with effectiveness, efficiency, and satisfaction in a specified context of use"). Dependent variable was the self-report of number of brochures distributed to patients. RESULTS: Professionals' engagement with facilitated access measured by brochures handed out was not predicted by Perceived product usability, Level of Information and Communication Technology Use or Computer self-efficacy. Professionals who had actively engaged with the website (customization) provided significantly more brochures compared with those who had not (Coefficient B 15.7 CI95% 3.5-27.8). Professional's socio-demographic characteristics did not predict engagement in facilitated access. CONCLUSION: Professionals' Perceived product usability, Level of Information and Communication Technology Use and Computer self-efficacy were not associated to facilitated access. Active early engagement of health professionals with the website (customization) is a key predictor of subsequent engagement with facilitated access. PRACTICE IMPLICATIONS: Computer Self-Efficacy, Level of Information and Communication Technology Use and Perceived Product Usability are irrelevant for facilitated access and efforts should be focused on taking time to collaborate with providers and convincing them about the usefulness of the intervention (including customization). Website customization by health care professionals is a promising predictor of engagement.

Impact of primary healthcare providers' initial role security and therapeutic commitment on implementing brief interventions in managing risky alcohol consumption: a cluster randomised factorial trial.

BACKGROUND: Brief interventions in primary healthcare are cost-effective in reducing drinking problems but poorly implemented in routine practice. Although evidence about implementing brief interventions is growing, knowledge is limited with regard to impact of initial role security and therapeutic commitment on brief intervention implementation. METHODS: In a cluster randomised factorial trial, 120 primary healthcare units (PHCUs) were randomised to eight groups: care as usual, training and support, financial reimbursement, and the opportunity to refer patients to an internet-based brief intervention (e-BI); paired combinations of these three strategies, and all three strategies combined. To explore the impact of initial role security and therapeutic commitment on implementing brief interventions, we performed multilevel linear regression analyses adapted to the factorial design. RESULTS: Data from 746 providers from 120 PHCUs were included in the analyses. Baseline role security and therapeutic commitment were found not to influence implementation of brief interventions. Furthermore, there were no significant interactions between these characteristics and allocated implementation groups. CONCLUSIONS: The extent to which providers changed their brief intervention delivery following experience of different implementation strategies was not determined by their initial attitudes towards alcohol problems. In future research, more attention is needed to unravel the causal relation between practitioners' attitudes, their actual behaviour and care improvement strategies to enhance implementation science. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01501552.

Improving the delivery of brief interventions for heavy drinking in primary health care: outcome results of the Optimizing Delivery of Health Care Intervention (ODHIN) five-country cluster randomized factorial trial.

AIM: To test if training and support, financial reimbursement and option of referring screen-positive patients to an internet-based method of giving advice (eBI) can increase primary health-care providers' delivery of Alcohol Use Disorders Identification Test (AUDIT)-C-based screening and advice to heavy drinkers. DESIGN: Cluster randomized factorial trial with 12-week implementation and measurement period. SETTING: Primary health-care units (PHCU) in different locations throughout Catalonia, England, the Netherlands, Poland and Sweden. PARTICIPANTS: A total of 120 PHCU, 24 in each of Catalonia, England, the Netherlands, Poland and Sweden. INTERVENTIONS: PHCUs were randomized to one of eight groups: care as usual, training and support (TS), financial reimbursement (FR) and eBI; paired combinations of TS, FR and eBI, and all of FR, TS and eBI. MEASUREMENTS: The primary outcome measure was the proportion of eligible adult (age 18+ years) patients screened during a 12-week implementation period. Secondary outcome measures were proportion of screen-positive patients advised; and proportion of consulting adult patients given an intervention (screening and advice to screen-positives) during the same 12-week implementation period. FINDINGS: During a 4-week baseline measurement period, the proportion of consulting adult patients who were screened for their alcohol consumption was 0.059 per PHCU (95% CI 0.034 to 0.084). Based on the factorial design, the ratio of the logged proportion screened during the 12-week implementation period was 1.48 (95% CI = 1.13-1.95) in PHCU that received TS versus PHCU that did not receive TS; for FR, the ratio was 2.00 (95% CI = 1.56-2.56). The option of referral to eBI did not lead to a higher proportion of patients screened. The ratio for TS plus FR was 2.34 (95% CI = 1.77-3.10), and the ratio for TS plus FR plus eBI was1.68 (95% CI = 1.11-2.53). CONCLUSIONS: Providing primary health-care units with training, support and financial reimbursement for delivering Alcohol Use Disorders Identification Test-C-based screening and advice to heavy drinkers increases screening for alcohol consumption. Providing primary health-care units with the option of referring screen-positive patients to an internet-based method of giving advice does not appear to increase screening for alcohol consumption.

[Implementation of an ERAS program in liver surgery]. / Implantación de un programa ERAS en cirugía hepática.

The perioperative management of patients undergoing abdominal surgery has been based on traditional concepts and often not supported by scientific evidence. Recently there have been several scientific studies showing that some traditional procedures for the perioperative management of patients as preoperative fasting, bowel preparation, use of naso-gastric tubes, placement of intra-abdominal drainage, postoperative fasting etc. They are unnecessary and sometimes counterproductive. Perioperative management protocols ERAS or Fast-Track (Enhanced Recovery After Surgery) are based on the use in the perioperative period of measures that are supported by current scientific evidence. Since 2000 appear in the scientific literature several works that reflect the application of protocols ERAS or Fast- Track in surgery of the digestive system where it's shown uniformly, not only the security of your application but also, decreased complications and hospital stay. Although initially these protocols were described in colorectal surgery, due to the good results obtained, the application of these protocols has rapidly expanded to other surgical specialties such as thoracic surgery, Urology, Gynaecology, etc. In all these specialties has unanimously showing improved postoperative recovery with ERAS application protocols. The purpose of this paper is twofold. On the one hand examine the scientific evidence that exists today on the most important elements of an ERAS program and present preliminary results of the implementation of a program ERAS in our hospital.

Implantación de un programa ERAS en cirugía hepática / Implementation of an ERAS program in liver surgery

El manejo perioperatorio de los pacientes sometidos a cirugía abdominal se ha basado en conceptos tradicionales y frecuentemente no avalados por la evidencia científica. Recientemente han aparecido varios estudios científicos que demuestran que algunos procedimientos tradicionales para el manejo perioperatororio de los pacientes como, el ayuno preoperatorio, la preparación intestinal, el uso de sondas naso-gástricas, la colocación de drenajes intraabdominales, el ayuno en el postoperatorio etc., son innecesarios e incluso a veces contraproducentes. Los protocolos de manejo perioperatorio de ERAS o Fast-Track (Enhanced Recovery After Surgery) se basan en la utilización de medidas en el periodo perioperatorio que están avaladas por la evidencia científica actual. A partir del año 2000 empiezan a aparecer en la bibliografía científica varios trabajos que recogen la aplicación de protocolos ERAS o Fast- Track en la cirugía del aparato digestivo en los que se nuestra de manera uniforme, no solo la seguridad de su aplicación sino también, la disminución de las complicaciones y de la estancia postoperatoria. Aunque inicialmente estos protocolos fueron descritos en la cirugía colo-rectal, debido a los buenos resultados obtenidos, la aplicación de estos protocolos se ha expandido rápidamente a otras especialidades quirúrgicas como la cirugía torácica, la Urología, la Ginecología, etc. En todos estas especialidades se ha mostrando de forma unánime la mejoría de la recuperación postoperatoria con la aplicación de protocolos ERAS. El motivo de este artículo es doble. Por un lado examinar la evidencia científica que existe en la actualidad sobre los elementos mas importantes de un programa ERAS y presentar los resultados preliminares de la implantación (AU)

The perioperative management of patients undergoing abdominal surgery has been based on traditional concepts and often not supported by scientific evidence. Recently there have been several scientific studies showing that some traditional procedures for the perioperative management of patients as preoperative fasting, bowel preparation, use of naso-gastric tubes, placement of intra-abdominal drainage, postoperative fasting etc. They are unnecessary and sometimes counterproductive. Perioperative management protocols ERAS or FastTrack (Enhanced Recovery After Surgery) are based on the use in the perioperative period of measures that are supported by current scientific evidence. Since 2000 appear in the scientific literature several works that reflect the application of protocols ERAS or Fast- Track in surgery of the digestive system where it´s shown uniformly, not only the security of your application but also, decreased complications and hospital stay. Although initially these protocols were described in colorectal surgery, due to the good results obtained, the application of these protocols has rapidly expanded to other surgical specialties such as thoracic surgery, Urology, Gynaecology, etc. In all these specialties has unanimously showing improved postoperative recovery with ERAS application protocols. The purpose of this paper is twofold. On the one hand examine the scientific evidence that exists today on the most important elements of an ERAS program and present preliminary results of the implementation of a program ERAS in our hospital (AU)

Professional's Attitudes Do Not Influence Screening and Brief Interventions Rates for Hazardous and Harmful Drinkers: Results from ODHIN Study.

AIMS: To determine the relation between existing levels of alcohol screening and brief intervention rates in five European jurisdictions and role security and therapeutic commitment by the participating primary healthcare professionals. METHODS: Health care professionals consisting of, 409 GPs, 282 nurses and 55 other staff including psychologists, social workers and nurse aids from 120 primary health care centres participated in a cross-sectional 4-week survey. The participants registered all screening and brief intervention activities as part of their normal routine. The participants also completed the Shortened Alcohol and Alcohol Problems Perception Questionnaire (SAAPPQ), which measure role security and therapeutic commitment. RESULTS: The only significant but small relationship was found between role security and screening rate in a multilevel logistic regression analysis adjusted for occupation of the provider, number of eligible patients and the random effects of jurisdictions and primary health care units (PHCU). No significant relationship was found between role security and brief intervention rate nor between therapeutic commitment and screening rate/brief intervention rate. The proportion of patients screened varied across jurisdictions between 2 and 10%. CONCLUSION: The findings show that the studied factors (role security and therapeutic commitment) are not of great importance for alcohol screening and BI rates. Given the fact that screening and brief intervention implementation rate has not changed much in the last decade in spite of increased policy emphasis, training initiatives and more research being published, this raises a question about what else is needed to enhance implementation.

A randomised controlled non-inferiority trial of primary care-based facilitated access to an alcohol reduction website (EFAR Spain): the study protocol.

INTRODUCTION: Early identification (EI) and brief interventions (BIs) for risky drinkers are effective tools in primary care. Lack of time in daily practice has been identified as one of the main barriers to implementation of BI. There is growing evidence that facilitated access by primary healthcare professionals (PHCPs) to a web-based BI can be a time-saving alternative to standard face-to-face BIs, but there is as yet no evidence about the effectiveness of this approach relative to conventional BI. The main aim of this study is to test non-inferiority of facilitation to a web-based BI for risky drinkers delivered by PHCP against face-to-face BI. METHOD AND ANALYSIS: A randomised controlled non-inferiority trial comparing both interventions will be performed in primary care health centres in Catalonia, Spain. Unselected adult patients attending participating centres will be given a leaflet inviting them to log on to a website to complete the Alcohol Use Disorders Identification Test (AUDIT-C) alcohol screening questionnaire. Participants with positive results will be requested online to complete a trial module including consent, baseline assessment and randomisation to either face-to-face BI by the practitioner or BI via the alcohol reduction website. Follow-up assessment of risky drinking will be undertaken online at 3 months and 1 year using the full AUDIT and D5-EQD5 scale. Proportions of risky drinkers in each group will be calculated and non-inferiority assessed against a specified margin of 10%. Assuming reduction of 30% of risky drinkers receiving standard intervention, 1000 patients will be required to give 90% power to reject the null hypothesis. ETHICS AND DISSEMINATION: The protocol was approved by the Ethics Commmittee of IDIAP Jordi Gol i Gurina P14/028. The findings of the trial will be disseminated through peer-reviewed journals, national and international conference presentations. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov NCT02082990.

Mielolipoma adrenal gigante: revisión a propósito de un caso / Giant adrenal myelolipoma: case report and literature review

El mielolipoma adrenal es un tumor benigno, poco frecuente, compuesto por tejido adiposo maduro y elementos hematopoyéticos diversos. Su hallazgo suele ser incidental, aunque en ocasiones pueden alcanzar gran tamaño y causar dolor abdominal y otros síntomas clínicos. La ecografía y la tomografía computarizada son herramientas útiles en su diagnóstico. Los tumores pequeños (< 6 cm) y asintomáticos pueden tratarse de forma conservadora con vigilancia periódica y los > 6 cm o con síntomas pueden precisar tratamiento quirúrgico. Presentamos un caso de mielolipoma adrenal gigante y a continuación se realiza una revisión de la literatura (AU)

Adrenal myelolipomas are rare benign tumors comprising mature adipose tissue and diverse hematopoietic elements. These neoplasms are usually incidental findings, although bulky masses can generate abdominal pain as well as other symptoms related to compression of adjacent organs. Diagnosis is usually provided by ultrasonography or computed tomography. Asymptomatic patients with tumors with a maximum diameter of less than 6 cm can benefit from periodic surveillance, whereas local compression symptoms and size larger than 6 cm are indications for surgical treatment. We present a case of giant adrenal myelolipoma (..) (AU)

Giant adrenal myelolipoma: case report and literature review.

Adrenal myelolipomas are rare benign tumors comprising mature adipose tissue and diverse hematopoietic elements. These neoplasms are usually incidental findings, although bulky masses can generate abdominal pain as well as other symptoms related to compression of adjacent organs. Diagnosis is usually provided by ultrasonography or computed tomography. Asymptomatic patients with tumors with a maximum diameter of less than 6cm can benefit from periodic surveillance, whereas local compression symptoms and size larger than 6cm are indications for surgical treatment. We present a case of giant adrenal myelolipoma and provide a review of the literature.

Seudoquiste adrenal gigante: a propósito de un caso / Giant adrenal pseudocyst: a case report

Los seudoquistes adrenales son las lesiones quísticas más frecuentes de la glándula suprarrenal, si bien constituyen una entidad rara. Suelen ser asintomáticas, pero pueden producir clínica inespecífica como dolor abdominal o lumbar. Se recomienda tratamiento quirúrgico si son sintomáticos o se sospecha malignidad. Presentamos un caso de un seudoquiste adrenal hemorrágico gigante con un antecedente de traumatismo como posible etiología (AU)

Although rare, adrenal pseudocysts are the most common cystic masses occurring in the adrenal gland. These lesions are usually asymptomatic, although they can produce nonspecific symptoms such as abdominal or lumbar pain. Surgical treatment is warranted only when adrenal pseudocysts are symptomatic or show imaging features suspicious for malignancy. We present a case of a giant hemorrhagic adrenal pseudocyst, possibly related to previous local trauma (AU)

[Functional nutrition and optimal nutrition. Near or far?]. / Alimentos funcionales y nutrición óptima. Cerca o lejos?

The concept of functional food, about which scientific agreement is still lacking, springs from the field of Optimum Nutrition, aimed at modifying genetic and physiological aspects of human life and at the prevention and treatment of a growing number of diseases, far beyond merely covering nutritional requirements. From the European Union perspective, functional foods can be natural as well as industrially processed foods. The leading functional foods regarding which the soundest scientific evidence exists are probiotics, live microbial food ingredients represented mainly by fermented dairy products. Prebiotics, such as inulin-type fructans, are the trophic substrate of probiotics and potential intestinal microflora selectors. The combination of prebiotics and probiotics is termed synbiotic. Innumerable substances are known to have functional effects: soluble and insoluble fiber, phytosterols, phytoestrogens, monounsaturated and polyunsaturated fatty acids, phenol derivatives, vitamins and other phytochemicals. Functional foods exert their actions on different systems, especially the gastrointestinal, cardiovascular and immunological ones, acting too as enhancers of development and differentiation and positively modulating nutrient metabolism, gene expression, oxidative stress and the psychic sphere. The establishment of Health Claims must be firmly based upon scientific knowledge and legal regulation. Efficient biomarkers related to biological response must be found. Furthermore, it is essential to analyze possible diet or drug interactions as well as it is indispensable to conduct valid studies on humans. The prime objective must be the diet as a whole. Thus, the future challenge of a functional diet emerges.

Alimentos funcionales y nutrición óptima.¿Cerca o lejos? / Functional Foods and Optimum Nutrition: A Way or Away?

El concepto de alimento funcional, aún no consensuado científicamente, surge en el seno de la Nutrición Óptima, encaminada a modificar aspectos genéticos y fisiológicos y a la prevención y tratamiento de enfermedades, más allá de la mera cobertura de las necesidades de nutrientes. Bajo la perspectiva de la Unión Europea, pueden ser tanto alimentos naturales como procesados industrialmente. Los alimentos funcionales más relevantes y sobre los que recae la más sólida evidencia científica son los probióticos, microorganismos vivos representados fundamentalmente por los derivados lácteos fermentados. Los prebióticos, como los fructanos tipo inulina, son el sustrato trófico de los probióticos y potenciales selectores de la flora colónica. La asociación de un prebiótico y un probiótico se denomina simbiótico. Se conocen innumerables sustancias con actividad funcional: fibra soluble e insoluble, fitosteroles, fitoestrógenos, ácidos grasos monoinsaturados y poliinsaturados, derivados fenólicos, vitaminas y otros fitoquímicos. Los alimentos funcionales ejercen su actividad en múltiples sistemas, especialmente el gastrointestinal, cardiovascular e inmunológico. Se comportan como potenciadores del desarrollo y la diferenciación, moduladores del metabolismo de nutrientes, la expresión génica, el estrés oxidativo y la esfera psíquica. La construcción de alegaciones sanitarias dirigidas al consumidor debe cimentarse en el conocimiento científico y la regulación legal. Es preciso encontrar biomarcadores eficientes del efecto biológico, analizar las posibles interacciones y realizar estudios válidos en humanos. El objetivo prioritario, sin embargo, debe ser la dieta en su conjunto. Emerge así el futuro reto de una dieta funcional (AU)

The concept of functional food, about which scientific agreement is still lacking, springs from the field of Optimum Nutrition, aimed at modifying genetic and physiological aspects of human life and at the prevention and treatment of a growing number of diseases, far beyond merely covering nutritional requirements. From the European Union perspective, functional foods can be natural as well as industrially processed foods. The leading functional foods regarding which the soundest scientific evidence exists are probiotics, live microbial food ingredients represented mainly by fermented dairy products. Prebiotics, such as inulin-type fructans, are the trophic substrate of probiotics and potential intestinal microflora selectors. The combination of prebiotics and probiotics is termed synbiotic. Innumerable substances are known to have functional effects: soluble and insoluble fiber, phytosterols, phytoestrogens, monounsaturated and polyunsaturated fatty acids, phenol derivatives, vitamins and other phytochemicals. Functional foods exert their actions on different systems, especially the gastrointestinal, cardiovascular and immunological ones, acting too as enhancers of development and differentiation and positively modulating nutrient metabolism, gene expression, oxidative stress and the psychic sphere. The establishment of Health Claims must be firmly based upon scientific knowledge and legal regulation. Efficient biomarkers related to biological response must be found. Furthermore, it is essential to analyze possible diet or drug interactions as well as it is indispensable to conduct valid studies on humans. The prime objective must be the diet as a whole. Thus, the future challenge of a functional diet emerges (AU)