Obesity has become an international epidemic. To evaluate the level of metals in extracts of plants prescribed as weight loss supplements, different brands containing Camellia sinensis (L.) Kuntze, Citrus aurantium L., Cordia ecalyculata Vell, Ilex paraguariensis A. St.-Hil, Cissus quadrangularis L., Senna alexandrina Mill were purchased in local market, hot acid digested, and analyzed while metal content by inductively coupled plasma optical emission spectrometry, ICP-OES. Quality assurance and quality control tests were carried out in order to monitor and control the reliability of the analytical method. For each metal evaluated, a calibration curve was prepared with certified reference material. The recovery test was performed for each batch of samples. Analyses were performed in triplicate. Quantification of aluminum, barium, cadmium, cobalt, chromium, copper, iron, lithium, manganese, molybdenum, nickel, lead, vanadium, and zinc were determined. The metals most frequently detected were manganese (15.3-329,60 mg kg) aluminum (11.76-342.4 mg kg), and iron (11.14-73.01 mg kg) with higher levels in products containing C. sinensis China origin, I. paraguariensis Brazilian origin, C. quadrangularis, and C. aurantium China origin, respectively. To ensure safety consumption, an adequacy of the certification of Brazilian suppliers for herbal weight loss products is indispensable.

Contrast-induced nephropathy (NIC) is directly related to increased morbidity and mortality, and its treatment and prevention might be achieved by the administration of antioxidant products. The juçara palmetto (Euterpe edulis Martius) has fruits rich in phenolic compounds, which are known for their antioxidant activity. This work aimed to evaluate the nephroprotective activity of E. edulis pulp in the NIC animal model. The collected fruits were pulped, their contents of polyphenols and anthocyanins were quantified, and their antioxidant activity were evaluated. The nephroprotective effects were determined based on iodine contrast induction and evaluated by biochemical and histological analyses. The results showed that E. edulis pulp was rich in polyphenols (811 ± 16.7 mg EAG/g) and anthocyanins (181.25 mg/100 g) and had very strong antioxidant activity, as demonstrated by the DPPH (2,2-diphenyl-1picryl-hydrazyl) method, which revealed an antioxidant activity index (AAI) of 3.4, and the 2,29-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) method, which revealed an IC 50 of 0.59 ± 0.03 mg/mL. In the in vivo experiments, E. edulis pulp tended to provide renal protection and reduce renal dysfunction and tubular morphological lesions in mice after the induction of NIC, and these effects were obtained through the antioxidant activities of the polyphenols in the pulp.