Phytosterols in supplements containing Serenoa repens: an example of variability of active principles in commercial plant based products.

Phytosterols are one of the bioactive components responsible for the beneficial effects of Serenoa repens in Benign Prostate Hyperplasia. The aim of this study was to verify the actual variability of the phytosterols content in supplements containing serenoa, in order to provide useful elements to check the effectiveness of these preparations. The amount of campesterol, stigmasterol and ß-sitosterol were determined by gas-chromatography in commercial raw materials and supplements containing serenoa in association or not with other botanicals. The experimental data were used to calculate amounts of phytosterols for recommended daily dose. The overall results of this study show an extreme variability in the content and also in the amounts per daily dose of phytosterols of the examined supplements (both mono/multi components). These data confirm that the characterization of serenoa based supplements is insufficient to ensure comparable effects between different products.

Use of food supplements and determinants of usage in a sample Italian adult population.

OBJECTIVE: The aims were to collect data on consumption of different food supplements in a sample of the adult Italian population and to characterize users by demographic, physical and health-related characteristics, lifestyle and behaviour. DESIGN: Cross-sectional survey. SETTING: The study was conducted in 2008 in ten towns of Italy (two towns from each of the five macro-areas: Northwest, Northeast, Centre, South and Islands). SUBJECTS: Adults (n 10 000) aged ≥18 years were randomly selected and asked to fill in a self-administered questionnaire regarding their use of food supplements and the above variables. The effect of these variables on food supplement use was evaluated by univariate and multivariate logistic regression. RESULTS: Of the 1723 individuals who returned the questionnaire, 49% were users of food supplements. A large proportion (54%) of users used more than one category of food supplement: vitamin and/or mineral supplements were the most used (61%), followed by supplements with botanicals and botanical extracts (28%). The results obtained by logistic regression showed that gender, town size, education level, sports practice, regular use of wholemeal cereal-based foods and presence of a low stress level were determinants for the use of food supplements in the examined population. However, these determinants were not shared by all categories of supplements. CONCLUSIONS: The results of this preliminary study highlight that associations between demographic, dietary and lifestyle factors and use of different categories of food supplements differ according to products, and cannot be accounted for simply by dichotomizing individuals as users or non-users.

Plants and parts of plants used in food supplements: an approach to their safety assessments.

In Italy most herbal products are sold as food supplements and are subject only to food law. A list of about 1200 plants authorised for use in food supplements has been compiled by the Italian Ministry of Health. In order to review and possibly improve the Ministry's list an ad hoc working group of Istituto Superiore di Sanità was requested to provide a technical and scientific opinion on plant safety. The listed plants were evaluated on the basis of their use in food, therapeutic activity, human toxicity and in no-alimentary fields. Toxicity was also assessed and plant limitations to use in food supplements were defined.

Convenient TLC for the detection of a herbal ingredient in a food supplement.

This study describes a practical and suitable approach to solve a real problem: the analysis of polyherbal products for which some specifications addressing the composition are lacking (e.g. chemical components). It is reported that an analytical procedure to verify the possible presence in a botanical supplement of a plant is not authorised for use in Italy. No reference of chemical standards for the known components of the plant is commercially available. For this reason and because a rapid response was required, more selective chromatographic techniques such as high-performance liquid chromatography, gas chromatography and liquid chromatography-mass spectrometry were excluded and thin layer chromatography was chosen for applying different experimental procedures. The original English label of the product, which is made by a leading US manufacturer and sold online by American and Italian distributors, lists the same herbal ingredients as the Italian label, but with an addition of Eurycoma longifolia Jack, which is not included in the list of plants admitted in supplements compiled by the Italian Ministry of Health. For greater certainty of the result, a high-performance thin layer chromatography method was then applied. On the basis of the results obtained, it was possible to confirm that E. longifolia Jack was not present in the product.

Reliability of a self-administered postal questionnaire on the use of food supplements in an italian adult population.

The objective of this study was to evaluate the reliability of a self-administered postal questionnaire on the use of food supplements. The study was carried out in subjects representative of an Italian adult population. Eight thousand eight hundred twenty-three subjects received the questionnaire; 1723 subjects completed it of which 102 twice (baseline and 1-month re-administration). The latter 204 questionnaires were used to test reliability using Cohen's kappa statistic (k) and the intra-class correlation coefficient (ICC) for categorical and quantitative variables, respectively. Subjects' characteristics such as sociodemographic and physical data, lifestyles, dietary habits, and most health characteristics showed very good agreement (ICC or k 1.00-0.55) between questionnaires, with the exception of answers about the consumption of some medicines (k 0.37-0.40). The reliability concerning the use of food supplements was satisfactory on the whole (k 0.69) and fairly satisfactory for different categories of food supplements (k 0.83-0.41). With regard to additional information about users of food supplements, the reliability of responses was fairly satisfactory on the whole (k 0.93-0.41), with some exceptions. The concordance/correlation coefficient values generally showed that the questionnaire is fairly reliable over the entire sample for collecting information on the use of food supplements.

Determination of alpha-amylase inhibitor activity of phaseolamin from kidney bean (Phaseolus vulgaris) in dietary supplements by HPAEC-PAD.

Some dietary supplements, so-called 'starch-blockers', used to control overweight, are based on the protein concentrate of the kidney bean, known to contain high levels of the alpha-amylase inhibitor phaseolamin, which may hinder the digestion of complex carbohydrates, thereby promoting or supporting weight loss. Currently, methods to determine the levels of alpha-amylase inhibitor are based on the measurement of alpha-amylase activity using colorimetric methods that cannot be applied to dietary supplements because they are complex mixtures of different ingredients that may interfere with the measurement. The aim of this study was to develop an alternative method to determine the level of phaseolamin in dietary supplements, using high-performance anion-exchange chromatography coupled with pulsed amperometric detection (HPAEC-PAD) to measure the amount of maltose resulting from the action of the enzyme porcine alpha-amylase on soluble starch in the presence and absence of the inhibitor. The assay described proved sensitive and accurate for use with both dietary supplements and raw materials.

[Biologically-active phytochemicals in vegetable food]. / Sostanze biologicamente attive presenti negli alimenti di origine vegetale.

Phytochemicals constitute a heterogeneous group of substances and evidence for their role in the protective effect on human health, when their dietary intake is significant, is emerging. These compounds have biological properties as antioxidant activity, modulation of detoxification enzymes, stimulation of the immune system, decrease of platelet aggregation and modulation of hormone metabolism. Glucosinolates and widely group of polyphenols, including the main category of flavonoids, are examined. Since their weak estrogenic activity is of interest at present, isoflavones are discussed at length. Numerous factors affect the phytochemical content and availability in plants; these factors include environmental conditions and industrial or domestic processing. The bioavailability of phytochemicals can be influenced by intrinsic factors in food and/or in human, in general the substances are little adsorbed, largely metabolized and rapidly eliminated. For this reason it is advisable that their consumption is constant in the time to maintain high concentrations of metabolites in the blood.

Influence of maternal protein intake on nitrogen fractions of human milk.

OBJECTIVES: Studies relating maternal diet to milk composition in humans have led to contradictory conclusions with regard to protein intake. The purpose of this paper was to examine if differences of protein intake in a group of lactating women can impact the protein and non-protein nitrogen fraction of their milk. SUBJECTS AND METHODS: Healthy lactating women(117) were recruited in Northern, Central, and Southern Italy. Their anthropometric measurements were obtained one month after delivery, while dietary evaluation was based on two consecutive 24-hour recalls. Infants' growth parameters were measured at birth and at one month. Milk collected at one month was analyzed for content of total nitrogen, protein nitrogen, non-protein nitrogen, and free amino acid profile. RESULTS: Maternal energy intakes were below the recommended values, while protein intakes were higher, with significant differences between geographical areas. There were no differences in the nitrogenous components of the milk examined with the exception of the non-protein nitrogen fraction and serine. Despite the different maternal intakes, no correlations were found between the mothers' parameters and milk components. CONCLUSION: This study shows that when protein requirements are met and there are no remarkable differences between intakes and requirements, there are no repercussions in nitrogen fractions.