Weight Loss Supplements Research Articles

Liquid chromatography-quadrupole time of flight mass spectrometric method for targeted analysis of 111 nitrogen-based compounds in weight loss and ergogenic supplements

The use of supplements for weight loss and in sports as pre-workout (ergogenic) products is widespread. Many of these supplements were found to contain active components, which were not claimed on the products labels. A validated liquid chromatography high-resolution mass spectrometry quadrupole time-of-flight (LC-QToF-MS) method was developed for the simultaneous analysis of 111 amine-based compounds belonging to ergogenics, anorectics and other active components including phenethylamines (amphetamines, ephedrines), sibutramine or yohimbine. This method involves the detection of [M+H]+ ions and the separation was achieved using a C18 column, water/acetonitrile gradient as the mobile phase. The method was validated for linearity, repeatability, accuracy, stability, system suitability, limits of quantification (LOQ) and limits of detection (LOD). The limits of detection were in the range from 0.001-0.5 μg/mL. The validated method was applied to the analysis of twenty-seven weight loss and ergogenic dietary supplements. Two-thirds of the supplements contained compounds that were not listed on the product’s label. These include several phenethylamines (PEA) such as demelverine, hordenine, N, N-dimethyl-phenethylamine, synephrine, N-methyl-β-phenethylamine, and methylsynephrine. In addition, the PEA mimics such as dimethylamylamine, dimethylbutylamine other stimulants including fursultiamine, evodiamine, phenibut and theophylline were also observed. One or more of the ingredients listed on the labels were not detected in forty-four percent of the products analyzed. Positive identification was based on retention time, accurate mass and fragment ions in comparison with the respective reference standards. Development of such methods is anticipated to be of aid to regulatory agencies for the identification of undeclared exogenous components that are found in many dietary supplement products.

Weight loss effect of sweet orange essential oil microcapsules on obese SD rats induced by high-fat diet.

Obesity is one of the most common and major health concerns worldwide. Weight management through dietary supplements with natural plant extracts has become the focus of current research. Sweet orange essential oil (SOEO) is a natural plant extract, with many bioactivities. In order to evaluate the weight loss effect of SOEO microcapsules and investigate the underlying mechanism, we fed high-fat diet-induced obese SD rats with SOEO microcapsules for 15days and found that SOEO microcapsules reduced body weight gain by 41.4%, decreased total cholesterol level, alleviated liver and adipose tissue pathological alteration. The results of fluorescence quantitative PCR revealed that decreasing the expression of peroxisome proliferators-activated receptor-γ, upregulating of uncoupling protein 2, hormone sensitive lipase and carnitine palmitoyltransferase I, inhibiting the expression of acetyl-CoA carboxylase appear to be the mechanism of SOEO microcapsules to lose weight. This study suggests that SOEO microcapsule is a potential dietary supplement for weight loss. Abbreviations: SOEO: sweet orange essential oil; TC: total cholesterol; TG: triglyceride; LDL-c: low-density lipoprotein cholesterol; HDL-c: high-density lipoprotein cholesterol; PPARα: peroxisome proliferators-activated receptor-α; PPARγ: peroxisome proliferators-activated receptor-γ; UCP2: uncoupling protein 2; HSL: hormone sensitive lipase; CPT1: carnitine palmitoyltransferase I; ACC: acetyl-CoA carboxylase; NPY: neuropeptide Y; LEP: leptin; INS: insulin; ALT: alanine aminotransferase; AST: aspartate aminotransferase.

FDA Warns of Hidden Prescription Drugs in Dietary Supplements.

The Food and Drug Administration has issued a warning that many products sold as dietary supplements for weight loss, sexual enhancement, or body building contain prescription drugs or other chemicals.Nurses and NPs should assess patients for use of these products and help them recognize those that are potentially tainted.

An Ultra-High Performance Liquid Chromatography-Electrospray Tandem Mass Spectrometric Method for Screening and Simultaneous Determination of Anorexic, Anxiolytic, Antidepressant, Diuretic, Laxative and Stimulant Drugs in Dietary Supplements Marketed for Weight Loss.

The consumption of dietary supplements is increasing every year all over the world and has been accompanied by an increased frequency of adulteration of these products with synthetic pharmaceuticals. Analytical methods that allow testing for the presence of synthetic drugs in dietary supplements are needed to detect such fraudulent practices. To investigate the adulteration of dietary supplements marketed for weight loss using different commercial appeals, we developed an analytical method using ultra-high-performance liquid chromatography-electrospray tandem mass spectrometry (UHPLC-ESI-MS/MS) for simultaneous determination of 32 drugs, including anorexics, anxiolytics, antidepressants, diuretics, laxatives and stimulants. Separation was accomplished in 19 minutes using a Zorbax SB-C18 column and a gradient elution program with 0.05% formic acid in water/acetonitrile as a mobile phase. Limits of quantification ranged from 0.14 to 3.92 μg L-1, and accuracy ranged from 80.00 to 119.48%. A simple extraction procedure was used in the pretreatment step by dissolving the samples in 100% methanol followed by a 1000 to 10,000-fold dilution in the mobile phase and filtration through a Teflon membrane (0.2 μm). The method was applied to the screening and quantification of the drugs in 108 formulations marketed as food supplements for slimming, weight loss, thermogenics, and supplements for meal replacement. Caffeine and p-synephrine were found as stimulants in 80 samples, listed or not on the label.

Nutritionist and obesity: brief overview on efficacy, safety, and drug interactions of the main weight-loss dietary supplements.

Over the past 20 years the use of dietary supplements as adjuvant therapy for weight loss gained growing favor among consumers and dietician-nutritionists, with the subsequent astounding increase in health costs. Despite the reassuring label of natural remedy for losing weight, dietary supplements contain a wide variety of ingredients on which available information is rather scanty and scientifically incomplete. Currently, there is little evidence that weight-loss supplements offer effective aids to reduce weight and meet criteria for recommended use. Robust, randomized, placebo-controlled studies to provide clear-cut scientific evidence of their efficacy and potential side effects in clinical practice are still lacking. Understanding the evidence for the efficacy, safety, and quality of these supplements among nutritionists and physicians is critical to counsel patients appropriately, especially considering the risk of serious adverse effects and interference with concomitant therapies. Detailed information on the efficacy and safety of the most commonly used weight-loss dietary supplements has been recently published by the National Institutes of Health (NIH). However, in this report the thorny issue that may result from drug interactions with weight-loss dietary supplements has been not sufficiently addressed. The aim of this review was to provide a synthetic, evidence-based report on efficacy and safety of the most commonly used ingredients in dietary supplements marketed for weight loss, particularly focusing on their possible drug interactions.

The Supplement Adulterant β-Methylphenethylamine Increases Blood Pressure by Acting at Peripheral Norepinephrine Transporters.

β-Methylphenethylamine [(BMPEA), 2-phenylpropan-1-amine] is a structural isomer of amphetamine (1-phenylpropan-2-amine) that has been identified in preworkout and weight loss supplements, yet little information is available about its pharmacology. Here, the neurochemical and cardiovascular effects of BMPEA and its analogs, N-methyl-2-phenylpropan-1-amine (MPPA) and N,N-dimethyl-2-phenylpropan-1-amine (DMPPA), were compared with structurally related amphetamines. As expected, amphetamine and methamphetamine were potent substrate-type releasing agents at dopamine transporters (DATs) and norepinephrine transporters (NETs) in rat brain synaptosomes. BMPEA and MPPA were also substrates at DATs and NETs, but they were at least 10-fold less potent than amphetamine. DMPPA was a weak substrate only at NETs. Importantly, the releasing actions of BMPEA and MPPA were more potent at NETs than DATs. Amphetamine produced significant dose-related increases in blood pressure (BP), heart rate (HR), and locomotor activity in conscious rats fitted with surgically implanted biotelemetry transmitters. BMPEA, MPPA, and DMPPA produced increases in BP that were similar to the effects of amphetamine, but the compounds failed to substantially affect HR or activity. The hypertensive effect of BMPEA was reversed by the α-adrenergic antagonist prazosin but not the ganglionic blocker chlorisondamine. Radioligand binding at various G protein-coupled receptors did not identify nontransporter sites of action that could account for cardiovascular effects of BMPEA or its analogs. Our results show that BMPEA, MPPA, and DMPPA are biologically active. The compounds are unlikely to be abused due to weak effects at DATs, but they could produce adverse cardiovascular effects via substrate activity at peripheral NET sites.

Guarana supplementation attenuated obesity, insulin resistance, and adipokines dysregulation induced by a standardized human Western diet via brown adipose tissue activation.

Obesity is a metabolic disorder associated with adverse health consequences that has increased worldwide at an epidemic rate. This has encouraged many people to utilize nonprescription herbal supplements for weight loss without knowledge of their safety or efficacy. However, mounting evidence has shown that some herbal supplements used for weight loss are associated with adverse effects. Guarana seed powder is a popular nonprescription dietary herb supplement marketed for weight loss, but no study has demonstrated its efficacy or safety when administered alone. Wistar rats were fed four different diets (low-fat diet and Western diet with or without guarana supplementation) for 18weeks. Metabolic parameters, gut microbiota changes, and toxicity were then characterized. Guarana seed powder supplementation prevented weight gain, insulin resistance, and adipokine dysregulation induced by Western diet compared with the control diet. Guarana induced brown adipose tissue expansion, mitochondrial biogenesis, uncoupling protein-1 overexpression, AMPK activation, and minor changes in gut microbiota. Molecular docking suggested a direct activation of AMPK by four guarana compounds tested here. We propose that brown adipose tissue activation is one of the action mechanisms involved in guarana supplementation-induced weight loss and that direct AMPK activation may underlie this mechanism. In summary, guarana is an attractive potential therapeutic agent to treat obesity.

Analiza zawartości kofeiny w suplementach diety wspomagających odchudzanie

Analiza zawartości kofeiny w suplementach diety wspomagających odchudzanie

Caffeine enhances activity thermogenesis and energy expenditure in rats.

Caffeine and its derivatives have been used, alone and in combination with other phytochemicals, as weight-loss supplements. Caffeine affects several physiological and behavioural aspects of energy balance, including increasing locomotor activity. This study investigates the potential for caffeine to enhance activity thermogenesis and energy expenditure (EE) even when activity level is held constant. To do this, EE and muscle thermogenesis were measured in rats during treadmill walking regimens, with and without caffeine (25mg/kg, ip). Activity-related EE was significantly increased throughout the treadmill walking protocol. Muscle heat dissipation, on the other hand, was significantly increased by caffeine only at the end of the 25-minute treadmill test. This study demonstrates that caffeine increases the caloric cost of physical activity, compared to the caloric cost of that same physical activity without caffeine, implicating decreased muscle work efficiency. Combined with the known ability of caffeine to increase locomotor activity, the decreased locomotor efficiency imparted by caffeine may further augment the potential for caffeine to enhance caloric expenditure.

Tissue-dependent effects of cis-9,trans-11- and trans-10,cis-12-CLA isomers on glucose and lipid metabolism in adult male mice

Mixtures of the two major conjugated linoleic acid (CLA) isomers trans-10,cis-12-CLA and cis-9,trans-11-CLA are used as over the counter supplements for weight loss. Because of the reported adverse effects of CLA on insulin sensitivity in some mouse studies, we sought to compare the impact of dietary t10c12-CLA and c9t11-CLA on liver, adipose tissue, and systemic metabolism of adult lean mice. We fed 8 week-old C57Bl/6J male mice with low fat diets (10.5% Kcal from fat) containing 0.8% t10c12-CLA or c9t11-CLA for 9 or 38 days. Diets containing c9t11-CLA had minimal impact on the endpoints studied. However, 7 days after starting the t10c12-CLA diet, we observed a dramatic reduction in fat mass measured by NMR spectroscopy, which interestingly rebounded by 38 days. This rebound was apparently due to a massive accumulation of lipids in the liver, because adipose tissue depots were visually undetectable. Hepatic steatosis and the disappearance of adipose tissue after t10c12-CLA feeding was associated with elevated plasma insulin levels and insulin resistance, compared to mice fed a control diet or c9t11-CLA diet. Unexpectedly, despite being insulin resistant, mice fed t10c12-CLA had normal levels of blood glucose, without signs of impaired glucose clearance. Hepatic gene expression and fatty acid composition suggested enhanced hepatic de novo lipogenesis without an increase in expression of gluconeogenic genes. These data indicate that dietary t10c12-CLA may alter hepatic glucose and lipid metabolism indirectly, in response to the loss of adipose tissue in mice fed a low fat diet.

English

Aristolochic acids are naturally occurring biomolecules found in plants of the genus Aristolochia and Asarum belonging to the family Aristolochiaceae. They are reported to be carcinogenic and nephrotoxic; and are implicated in kidney diseases, aristolochic acid nephropathy (AAN) which may result in kidney failure, other health complications and possibly death. Aristolochic acids are highly genotoxic and are linked to upper urothelial cancer in animals and humans. Some Aristolochia species are used in traditional medicine practice in Nigeria and other West African countries without regard to safety concerns. Several countries, especially in the Western world, have banned the use and importation of herbal products containing aristolochic acids. There is need for warning and strict regulation on the importation and consumption of aristolochic acids-containing botanical products in Nigeria. This study aims to review the availability of aristolochic acids, their toxicity, circulation, as well as the quantitative analytical techniques and regulations. It analyzes the herbal products containing aristolochic acids, and aristolochaceae plants grown in Nigeria in respect to public health implications. It highlights the importance of doing an extensive study on indigenous plants producing aristolochic acids and imported herbal products used as weight loss supplements marketed in Nigeria. There is need to emphasize the labeling of herbal products containing aristolochic acids. Key words: Aristolochic acid, herbal medicine, Nigeria, aristolochaceae, toxicity, regulation.

Consciousness Energy Healing Treatment: Spectroscopic and Calorimetric Evaluation of the Biofield Energy Treated Hydroxypropyl β-Cyclodextrin

Hydroxypropyl β-Cyclodextrin (HPBCD) used in food, pharmaceutical, chemical industries, as well as environmental, and agriculture engineering. But the major issue related to HPBCD is the low solubility profile. In this study, the influence of the Consciousness Energy Healing Treatment (the Trivedi Effect®) on the physicochemical properties of HPBCD was evaluated using spectroscopic and calorimetric analytical techniques. The test sample (HPBCD) was divided into control sample and treated sample. The control sample did not receive the Biofield Energy Treatment. Whereas, the treated sample received the Biofield Energy Treatment remotely by a renowned Biofield Energy Healer, Dahryn Trivedi. The particle size values of the treated sample were decreased by 3.28%(d10), 1.36%(d50), 0.45%(d90), and 1.04%{D(4,3)}; therefore, the specific surface area was increased by 1.9% compared with the control sample. The evaporation temperature of the treated HPBCD sample was significantly decreased by 19.89%; however, the latent heat of evaporation and latent heat of fusion were significantly increased by 56.27% and 47.41%, respectively compared with the control sample.The total weight loss in the treated HPBCD was decreased by 5.11%; whereas, the residue amount was significantly 309.67% more compared to the control sample.The results indicated that the Trivedi Effect® might have produced a new form of HPBCD which may show better thermal stability, solubility, dissolution rate, and bioavailability. This new form of HPBCD would be more useful for improvement of solubility of the lipophilic drug, preparation of cholesterol free food products, weight loss supplements, anti-obesity medication, stabilize volatile and unstable compounds, and other manufacturing industry using it as a raw material.

174. Community Stakeholders’ Perception And Attitudes About Dietary Supplements Use Among Adolescents: Lessons For Local Policy Initiatives

Dietary supplements are a lucrative industry in the United States. While many dietary supplements may be safe to use, those sold for weight loss and muscle building are known to often be adulterated with illegal substances, like steroids and prescription pharmaceuticals, and to include toxic concentrations of legal substances. The U.S. FDA only loosely regulates the safety of these products, and they are easily accessible to youth. The purpose of this study is to explore the perceptions and attitudes of key community stakeholders about the issue of dietary supplements sold for weight loss or muscle building to adolescents. Additionally, the study aims to identify barriers and opportunities to engage community stakeholders with policy initiatives at the local level to prevent sale of weight-loss and muscle-building dietary supplements to adolescents. We conducted 32 key informant semi-structured interviews in four Massachusetts municipalities with purposefully selected participants representing three categories of community stakeholders: policy professionals; health workers, teachers and coaches; and young adults (ages 18-25 years old) who used weight-loss or muscle-building dietary supplements as minors. In-person interviews were audio recorded, transcribed, and coded by the first author. Initially 20% of transcripts were reviewed to create a preliminary codebook, which was iterated through several rounds with coauthors. Then codebook was applied to the rest of dataset by the first author. During the coding process, the codebook was reviewed and adjusted based on emerging information. The coding was accompanied by analytic memo writing. Qualitative data analysis was based on thematic analysis approach and facilitated by Dedoose software. Community stakeholders reported wide availability and easy access of supplements sold for weight-loss and muscle-building purposes to youth, especially for those who are involved in athletics, who believe supplements are part of a healthy lifestyle and nutrition, and those vulnerable to developing of eating or body image disorders. All interviewees highlighted the influence of social media, family, and friends on youths’ decision to use supplements. However, there were contrasting perceptions of social acceptability and the role of socioeconomic status of households in youth supplements consumption. Most adults were unaware of known risks and side effects associated with use of these products. Many young adults described their experience during adolescence as consuming supplements without guidance from adults. The main barriers identified for engagement in policy initiatives to curtail youth access to these products were: competing concerns on the policy agenda; limited capacity of community stakeholders; and uncertainty about who has accountability for the problem. The following were identified as opportunities that would facilitate policies to curtail youth access: relevant local data; availability of research evidence of supplement harm; and community involvement. This study points to the need for complementary, multiple-pronged approaches at the municipal level to address the problem of weak regulation and easy access to potentially dangerous weight-loss and muscle-building supplements for youth.

Presence of undeclared caffeine in weight loss food supplements

Recent studies claim that weight loss supplements often contain pharmacoactive ingredients or undeclared drug substances with a potential health risk. This study is focused on food supplements in the category “weight loss” in which label caffeine was not declared. Analysed samples were purchased from dietary supplement stores, pharmacies and internet. In the screening were included only food supplements witch do not contain caffeine or herbal extracts which contain caffeine like guarana, kola nut, yerba mate etc. 30 samples were analysed by HPLC/UV detection. We found undeclared caffeine in 5 of the analysed samples. The presence of undeclared caffeine in food supplements for weight loss could lead to serious health consequences especially for consumers with cardiovascular disea

Effects of Thylakoid-Rich Spinach Extract on the Pharmacokinetics of Drugs in Rats.

Thylakoid-rich spinach extract is being used as dietary weight-loss supplements in Japan. A recent rat study has suggested that intake of thylakoid-rich spinach extract with dietary oil inhibits dietary fat absorption via binding to bile acids, which promotes excretion of bile acids in feces. While, we confirmed that a serving size of thylakoid-rich spinach extract contains a large amount of calcium (130 mg/5 g). Therefore, using rats, we evaluated whether one-time ingestion of thylakoid-rich spinach extract affects the gastrointestinal absorption of water-insoluble drugs, such as griseofulvin (GF) and indomethacin (IM), or ciprofloxacin (CPFX) that chelate with polyvalent metal cations. Pretreatment of the rats with thylakoid-rich spinach extract (100 or 300 mg/kg) for 15 min prior to oral administration of GF (50 mg/kg) or IM (10 mg/kg) did not significantly alter the pharmacokinetic properties of either drug. Meanwhile, co-administration of thylakoid-rich spinach extract (500 mg/kg) and CPFX (20 mg/kg) significantly reduced the peak plasma concentration and the area under the plasma concentration-time curve of CPFX to 25 and 40%, respectively in rats. In vitro studies demonstrated that when a mixture of thylakoid-rich spinach extract and CPFX was centrifuged, there was a significant reduction in the supernatant concentration of CPFX relative to the control. When the experiment was repeated in the presence of ethylenediaminetetraacetic acid, the concentration of CPFX was unchanged. These results suggest that the intake of thylakoid-rich spinach extract may reduce the absorption of drugs that form a chelate with polyvalent metal cations, such as CPFX.

Magnetic dispersive solid phase microextraction technique coupled with LC–MS/MS for evaluating content versus label claims in ephedrine-free food supplements

Sport supplements and weight management supplements are prime targets for adulteration. In response to concerns regarding the safety of ephedra-containing food supplements, manufacturers have marketed “ephedra-free” products. Therefore, a rapid and convenient magnetic dispersive solid phase microextraction method is proposed in order to extract ephedrine from complex food supplements. Quantification of ephedrine is accomplished by ion-spray LC–MS/MS using multiple reaction monitoring (MRM) mode. The LC–MS/MS method is validated in the range of 5–100 ng/mg. The proposed procedure is applied to the determination of ephedrine in various food supplements. Sixteen food supplements including sport and weight loss supplements are provided from two local drugstores (Tabriz, Iran). The mean content of the ephedrine, identified in five products, amounted to 1055 ng/mg. The proposed method is reliable and fast for determination of ephedrine content in food supplements.

Availability and composition of weight-loss supplements in Sri Lanka.

The present study aims to investigate the composition and availability of weight-loss supplements in Sri Lanka and explore the evidence for their effectiveness. Data were collected by visiting drug stores, searching the Internet for websites and referring to advertisements in national newspapers and magazines from August to October 2017. A total of 100 weight-loss products were identified of which the majority (n = 57) were available from drug stores. Most commonly, products were available in capsule form (36.0%). The number of active ingredients in products varied from 1 to a maximum of 22 with a total of 155 different active ingredients distinguished. The ingredients mainly originated from plants (77.4%) while green tea (Camellia sinensis), garcinia (Garcinia cambogia) and caffeine anhydrous were the three most common. At least one of the top 10 ingredients was included in 75 of the products sourced. Directions for use were specified in only 72 products, while a further 6 products lacked any information on ingredients. Literature predicted positive weight-loss effects for green tea and ginger while garcinia was reported for both positive and negative effects. The ingredients are reported to have both beneficial and adverse effects. Many consumers may find it challenging to make informed purchase decisions as a number of products failed to provide adequate nutritional information and safety measures. Government regulatory authorities should pay closer attention to the availability and provision of products sold to the general public.

Retrospective self-reported dietary supplement use by Australian military personnel during deployment to Iraq and Afghanistan: results from the Middle East Area of Operations Health Study.

The use of dietary supplements is popular among military personnel. However, there is a lack of understanding about the changes in use during deployment and the specific factors associated with such changes. This study retrospectively examined changes in the pattern of supplement use among Australian veterans during their deployment to Iraq (n = 8848) and Afghanistan (n = 6507) between 2001 and 2009 and identified work-related circumstances that were associated with these changes. The frequency of use of supplements at present and during deployment was assessed. Multiple logistic regression analysis was used to compare the use of supplements among different groups and among those with different deployment experiences. The study found that overall use of supplements was highest on deployment to Afghanistan (27.8%) compared with deployment to Iraq (22.0%, p < 0.001) or after deployment (current use, 21.2%; p < 0.001). Personnel who were younger or who were at the rank of noncommissioned officer were more likely to use dietary supplements. Men were more likely to use body-building supplements, whereas women more often used weight-loss supplements. Those veterans who did not report using supplements regularly on deployment were far less likely to use them subsequently. Combat exposure, mixed duty cycles, and working long hours during deployment were associated with higher supplement use. The findings confirmed that supplement use in the military reflects the unique demands and stressors of defence service.

Determination of Stimulants and Diuretics in Dietary Supplements for Weight Loss and Physical Fitness by Ion-pair Chromatography and Pulsed Amperometric Detection (PAD)

Determination of Stimulants and Diuretics in Dietary Supplements for Weight Loss and Physical Fitness by Ion-pair Chromatography and Pulsed Amperometric Detection (PAD)

Unapproved Pharmaceutical Ingredients Included in Dietary Supplements Associated With US Food and Drug Administration Warnings

Over half of adults in the United States report consuming dietary supplements. The US Food and Drug Administration (FDA) has warned of numerous dietary supplements containing undeclared, unapproved pharmaceutical ingredients. These FDA warnings have not been comprehensively analyzed for recent years. To summarize trends across adulterated (containing unapproved ingredients) dietary supplements associated with a warning released by the FDA from 2007 through 2016. In this quality improvement study, data were extracted from the FDA's Center for Drug Evaluation and Research, Tainted Products Marketed as Dietary Supplements_CDER database from 2007 through 2016. Data from each warning were recorded unless multiple warnings were issued for the same product within a 6-month period. Date, product name, company, hidden ingredient(s), product category, source of sample, and warning document type were recorded for each included warning. Data analysis was conducted from February 2017 to June 2017. From 2007 through 2016, 776 adulterated dietary supplements were identified by the FDA and 146 different dietary supplement companies were implicated. Most of these products were marketed for sexual enhancement (353 [45.5%]), weight loss (317 [40.9%]), or muscle building (92 [11.9%]), with 157 adulterated products (20.2%) containing more than 1 unapproved ingredient. The most common adulterants were sildenafil for sexual enhancement supplements (166 of 353 [47.0%]), sibutramine for weight loss supplements (269 of 317 [84.9%]), and synthetic steroids or steroid-like ingredients for muscle building supplements (82 of 92 [89.1%]). There were 28 products named in 2 or 3 warnings more than 6 months apart. Of these products, 19 (67.9%) were reported to contain new unapproved ingredients in the second or third warning, consistent with the assumption that the FDA found the product to be adulterated more than once. In recent years (2014-2016), 117 of 303 adulterated samples (38.6%) were identified through online sampling and 104 of 303 (34.3%) were identified through the examination of international mail shipments. Active pharmaceuticals continue to be identified in dietary supplements, especially those marketed for sexual enhancement or weight loss, even after FDA warnings. The drug ingredients in these dietary supplements have the potential to cause serious adverse health effects owing to accidental misuse, overuse, or interaction with other medications, underlying health conditions, or other pharmaceuticals within the supplement.