Is the Magnesium Content in Food Supplements Consistent with the Manufacturers' Declarations?

Food Supplements Containing Iron-Comparison of Actual Content with Declared Content and Health Consequences

The use of food supplements (FSs) is becoming an increasingly common trend observed in society. This is related to frequently observed nutritional deficiencies and the inability to provide sufficient amounts of nutrients, including vitamins and minerals, through the diet. The ease of registering FSs sometimes results in low-quality preparations on the market. Therefore, our research aimed to assess the content of one of the most popular trace element components, iron (Fe), in FSs available in Poland. This study covered 109 preparations purchased from stationary pharmacies and online pharmacies. The following criteria were used to characterize FSs in the data analysis: the Fe content declared by the manufacturer, pharmaceutical form, type of Fe salt, manufacturer's country of origin, contents of other trace elements or minerals, presence of additional ingredients, age of the target group, and addition of vitamins B2, B6, B12, and C. The Fe content was quantified using atomic absorption spectrometry after mineralization using microwaves. It was demonstrated that 69.73% of the preparations contained more Fe than the value declared by the manufacturer (and corrected for permissible deviations), 11.00% contained less Fe than declared, and only 19.27% were within the norm. In summary, the FS market requires the improvement of manufacturing processes and increased control, which should translate into patient safety.

In Vitro Evaluation of Bioavailability of Cr from Daily Food Rations and Dietary Supplements from the Polish Market

Only some of the nutrients consumed with food are able to be absorbed from the gastrointestinal (GI) tract and enter the systemic circulation (blood). Because some elements are essential minerals for humans, their beneficial effect on the body depends significantly on their bioavailable amount (the fraction that can be absorbed and used by the organism). The term bioavailability, which is very often used to describe the part of nutrients that is able to be absorbed, is influenced by various factors of exogenous and endogenous origin. The main purpose of the study was to assess the relative bioavailability of Cr from selected dietary supplements in the presence of various types of diets, which significantly influence the level of bioavailability. The research was performed using a previously developed and optimized two-stage in vitro digestion model using cellulose dialysis tubes of food rations with the addition of pharmaceutical products. Cr was determined using the ICP-OES and GF-AAS methods, depending on its concentration in particular fractions. The determined relative bioavailability ranged between 2.97 and 3.70%. The results of the study revealed that the type of diet, the chemical form of the molecule, and the pharmaceutical form of preparations have a significant influence on the bioavailability of Cr.

In Vitro Evaluation of Bioavailability of Se from Daily Food Rations and Dietary Supplements

Bioavailability refers to a fraction of a substance that is potentially absorbed from the gastrointestinal tract and enters the systemic circulation (blood). This term is related to various substances, including minerals, that are present in a complex matrix of food which is consumed every day as natural products and pharmaceutical preparations, e.g., dietary supplements. The purpose of the study was to assess the bioavailability of Se from selected dietary supplements, with the simultaneous assessment of the effect the diet type (standard, basic and high-residue diets) has on relative bioavailability. The research included a two-stage in vitro model of digestion using cellulose dialysis tubes of the food rations with the addition of dietary supplements. Se was determined using the ICP-OES method. The bioavailability of Se from dietary supplements, in the presence of food matrix, was determined to be within the range of 19.31-66.10%. Sodium selenate was characterized by the highest value of this parameter, followed by organic forms and sodium selenite. The basic diet, characterized by moderate protein and high carbohydrate and fiber contents, positively influenced the bioavailability of Se. The bioavailability of Se was also influenced by the pharmaceutical form of the product-the highest was for tablets, followed by capsules and coated tablets.

Resveratrol Food Supplement Products and the Challenges of Accurate Label Information to Ensure Food Safety for Consumers

The food supplement market is growing as many consumers wish to complement their nutrient intake. Despite all the regulations in place to ensure food supplements safety, there are still many cases of irregularities reported especially connected to internet sales. Twenty resveratrol food supplement products sold on the Slovenian market were evaluated on their compliance of declared vs. determined resveratrol content, as well as the compliance of labels with the European Union (EU) and Slovenian regulatory requirements. Both the ingredient contents and food information are important parts of food safety. Analyses of 20 food supplements performed using high-performance thin-layer chromatography (HPTLC) coupled with densitometry showed that 95% of products had contents different from what was declared and 55% of products contained higher contents than declared. In 25% of the products the determined content per unit exceeded the maximum level (150 mg/day) specified in EU novel food conditions for food supplement with trans-resveratrol. Evaluation of the 20 food supplement labels included mandatory and voluntary food information, food supplement information, novel food information, health claims and nutrition claims. Most labels contained the necessary information, but multiple errors were observed ranging from typos to misleading practices. From a food safety perspective there is still a lot of improvement needed in the field of food supplements.

Mineral Composition of Dietary Supplements-Analytical and Chemometric Approach

There is a lack of data on the actual composition and effectiveness of beetroot-based dietary supplements. The research aimed to determine the profile of 22 elements (Na, K, Ca, Mg, P, Fe, As, Se, Zn, Cu, Ag, Co, Ni, Mo, Al, Mn, Sr, Cr, Ba, Li, Pb, Cd) in beetroot and its supplements by the microwave plasma atomic emission spectrometry (MP-AES) method. The analytical procedure was optimised and validated. The composition of both groups was compared, assessing compliance with the recommended daily doses for the chosen elements, and the health risk was estimated. Furthermore, chemometric analysis was applied. Beetroots constituted a significant source of elements, especially K, Na, Mg, Ca, P, in contrast to supplements which contained their negligible amounts except from iron-enriched products which provided notable amounts of Fe (38.3–88% of the Recommended Dietary Allowance for an adult male from 19 to 75 years old). Some products were significantly contaminated with toxic elements (As, Cd). Factor and cluster analyses were helpful in the differentiation of beetroot and its supplements in view of their type (vegetable, supplement, iron-enriched supplement), origin, type of cultivation (conventional, organic), and form (capsule, tablet) based on their mineral composition. The obtained results indicate the need for more stringent control of supplements, as they may pose a significant health risk to consumers.