Hepatotoxicity associated with weight loss or sports dietary supplements, including OxyELITE Pro™ - United States, 2013

A Behaviourally Informed Approach to Reducing the Risk of Inadvertent Anti-doping Rule Violations from Supplement Use

For many reasons, athletes' use of supplements is highly prevalent across sports and competitive levels, despite the risk of these products containing a substance on the World Anti-Doping Agency Prohibited List. Contravening anti-doping rules through supplement use could have serious consequences for competitive athletes (e.g., ineligibility from major competitions, loss of medals and funding) due to the principle of strict liability. Indiscriminate supplement use also poses a risk to athlete health. To reduce the possibility of ingesting a supplement containing prohibited substances, independent quality assurance and certification programs have been established (e.g., Informed Sport). However, these programs do not completely eliminate risk, leading to some anti-doping organisations promoting a 'just say no' to supplements stance. Yet, this approach can be problematic as a small number of supplements may be necessary for athletes to consume, in certain situations. Recognising that athletes will continue to use these heavily marketed products, this narrative review describes a theoretically underpinned and systematic approach to preventing inadvertent doping by considering the barriers to and enablers of athlete adherence to risk minimisation supplement use guidelines (RMSUG). By outlining a conceptual shift towards a behaviourally informed approach, this review serves to stimulate the development of multifaceted interventions to prevent inadvertent doping through supplement use. Recognising that risk-minimised supplement use involves a myriad of behaviours, the problem of inadvertent doping through supplement use is framed, and research appraised, through the lens of the Behaviour Change Wheel.

Hepatotoxicity due to dietary supplements: state-of-the-art, gaps and perspectives

Food supplements are products intended to complement the normal diet and consist of concentrated sources of nutrients or other substances with a nutritional or physiological effect. Although they are generally considered safe if the manufacturer's recommendations are followed, many of them have shown hepatotoxic properties. This can cause many diseases (e.g. steatohepatitis and cirrhosis) characterized by progressive damage and malfunction of the liver that in the long term can lead to death. A review of the literature was carried out to elucidate which dietary supplements have been associated with cases of hepatotoxicity in recent years, with emphasis on those relevant to the consumer and the new trends (e.g. cannabidiol). It has been reported that the supplements described as hepatotoxic are mainly of botanical origin (e.g. green tea or turmeric) and those used in sports (mainly anabolic androgenic steroids). There is a great variability of compounds described as causing liver damage, although sometimes it is not possible to identify them, because they are contaminants or adulterants of the products. In addition, the prevalence of toxic effects after the administration of supplements is difficult to define due to underreporting and the lack of specific studies. Globally regarding hepatotoxicity of dietary supplements, there is a paucity of well-conducted clinical trials on the efficacy of these compounds and the frequency of related liver damage, as the use of these products is largely uncontrolled.

Weak regulations threaten the safety of consumers from harmful weight-loss supplements globally: results from a pilot global policy scan

OBJECTIVE

To pilot a global policy scan assessing how governments worldwide regulate weight-loss supplements (WLS).

DESIGN

Experts on WLS policies from thirty countries that varied by World Bank income classification, with five from each of the six WHO regions, completed an online survey on WLS regulation in their country. The survey covered six domains: legal frameworks; pre-market requirements; claims, labelling, and advertisements; product availability; adverse events reporting; and monitoring and enforcement. Percentages were calculated for presence or absence of a type of regulation.

SETTING

Experts were recruited through websites of regulatory bodies and professional LinkedIn networks and scientific article searches on Google Scholar.

PARTICIPANTS

Thirty experts, one from each country (i.e. researchers, regulators, other experts in food and drug regulation).

RESULTS

WLS regulations varied widely across countries, and a number of gaps were identified. One country (Nigeria) has a minimum legal age to purchase WLS. Thirteen countries reported independently evaluating the safety of a new WLS product sample. Two countries have limitations on where WLS can be sold. In eleven countries, reports on adverse events related to WLS are publicly available. In eighteen countries, safety of new WLS is to be established through scientific criteria. Penalties for WLS non-compliance with pre-market regulations exist in twelve countries and labelling requirements in sixteen countries.

CONCLUSIONS

Results of this pilot study document wide variability in national WLS regulations globally, exposing many gaps in important components of consumer protection regulatory frameworks for WLS, which likely put consumer health at risk.

Dietary supplement adulteration - knowledge, attitudes, and practices of California health care professionals: A cross-sectional survey study

OBJECTIVE

To assess knowledge, attitudes, and practices surrounding dietary supplements (DS) among California health care professionals (HCPs) and assess factors contributing to the frequency with which HCPs discuss DS with patients.

METHODS

In this cross-sectional study, an online questionnaire was distributed to HCPs in California from December 2021-April 2022 via professional membership email listservs.

RESULTS

Among 514 HCPs, overall knowledge of DS did not vary significantly by professional group, and 90% had received little to no DS education. Pharmacists (OR = 0.328, p = 0.0001) and those with less reported DS education (OR = 0.58, p = 0.0045; OR = 0.075, p = 0.0097) had a decreased likelihood of initiating conversations about DS more frequently. Females (OR = 2.5, p < 0.0001) and those with a higher knowledge score (OR = 1.2, p = 0.0297) had an increased likelihood of initiating conversations about DS more frequently.

CONCLUSIONS

HCPs acknowledge the clinical significance of DS adulteration and would benefit from additional informational resources to reduce the adverse effects associated with adulterated supplements.

PRACTICE IMPLICATIONS

HCPs initiate more conversations about DS use when they are more informed and will gain from staying up to date on DS-related information to encourage more patient communication.

Review article: clinical assessment of suspected drug-induced liver injury and its management

BACKGROUND

Idisyncratic drug-induced liver injury (DILI) is a rare instance of liver injury after exposure to an otherwise safe drug or herbal or dietary supplement. DILI can be associated with significant morbidity and mortality. Furthermore, it is an important consideration in drug development due to safety concerns.

AIMS AND METHODS

To highlight pearls and pitfalls to aid clinicians in diagnosing DILI and surmising the management options. We also share the best practices from personal insights developed from decades long participation in the causality assessment committee meetings of the DILI Network.

RESULTS

DILI lacks a diagnostic test and is currently diagnosed through a process of exclusion of competing aetiologies of liver injury. This requires a high degree of suspicion to consider the possibility of DILI, skill in ruling out the obvious and less obvious competing liver insults, and an understanding of the expected phenotypes of DILI. The facets of DILI cover multiple aspects, including the latency, liver injury pattern, course of injury, and associated autoimmune or immuno-allergic features. Care for patients with DILI is geared towards stopping the offending drug and symptom management that include the use of corticosteroids in select cases.

CONCLUSION

The diagnosis of DILI is challenging and is primarily made through a carefully crafted patient interview, temporal relationship with the implicated drug or supplement, and exclusion of competing aetiology. LiverTox is a useful resource for clinicians to review the literature and recognise the likelihood of the implicated agent in causing DILI.

Hepatotoxicity due to herbal dietary supplements: Past, present and the future

Dietary supplements (DS) constitute a widely used group of products comprising vitamin, mineral, and botanical extract formulations. DS of botanical or herbal origins (HDS) comprise nearly 30% of all DS and are presented on the market either as single plant extracts or multi-extract-containing products. Despite generally safe toxicological profiles of most products currently present on the market, rising cases of liver injury caused by HDS - mostly by multi-ingredient and adulterated products - are of particular concern. Here we discuss the most prominent historical cases of HDS-induced hepatotoxicty - from Ephedra to Hydroxycut and OxyELITE Pro-NF, as well as products with suspected hepatotoxicity that are either currently on or are entering the market. We further provide discussion on overcoming the existing challenges with HDS-linked hepatotoxicity by introduction of advanced in silico, in vitro, in vivo, and microphysiological system approaches to address the matter of safety of those products before they reach the market.

Use and safety of appearance and performance enhancing supplements in gay, bisexual, and other men who have sex with men receiving daily tenofovir disoproxil fumarate/emtricitabine as HIV pre-exposure prophylaxis

Appearance- and performance-enhancing supplements (APES) may be associated with liver and renal toxicity, but use is often under-reported. This study describes the use and safety of APES among gay, bisexual, and other men-who-have-sex with men (gbMSM) attending an urban HIV pre-exposure prophylaxis (PrEP) clinic. A cross-sectional study was conducted between February 2018 to September 2018 to assess APES usage in gbMSM taking daily tenofovir disoproxil fumarate/emtricitabine for PrEP. Renal and liver function were assessed from electronic medical records. Among 50 participants (98% male, median 32 years, 52% White, on PrEP for a median 4.4 years), 72% reported lifetime APES use, with 52% currently using APES (median 1.5 products/person) and 28% never used APES. The most common products included whey protein, creatine supplements and anabolic steroids. The primary reason for APES use was to increase muscle mass. Three (12%) current APES users had elevated serum creatinine (stage 1) versus zero (0%) in the non-APES group. Two (8%) current APES users experienced grade 3-4 ALT/AST elevations versus zero (0%) in the non-APES group. APES usage among gbMSM taking PrEP was high and may be associated with liver/renal lab abnormalities. Increased awareness of APES use and potential toxicity is encouraged to enhance safety.

Acute Liver Failure Caused by Use of Fat Burner: A Case Report

Acute liver failure is a rare condition consisting of abrupt and extensive hepatocyte injury, leading to significant liver dysfunction associated with a high mortality. Liver transplantation is the most effective treatment in severe cases. The most common cause of acute liver failure in Western countries is drug-induced liver injury caused by prescription drugs and herbal and dietary supplements. Thermogenics, or fat burners, are a category of dietary supplements that claim to increase the resting metabolic rate, leading to weight loss. There are previous reports of acute liver failure associated with specific thermogenic formulations. We report the case of a 36-year-old male patient who developed jaundice 7 days after he started taking a thermogenic dietary supplement (Thermo Gun), with progressive deterioration of hepatic function and development of hepatic encephalopathy 19 days after the beginning of the symptoms. He had a Model for End-Stage Liver Disease score of 38 and fulfilled 4 of the King's College Criteria for poor prognosis in patients with acute liver failure. He underwent liver transplantation, receiving a graft from a cadaveric donor, and is alive with good liver graft function 2 years after the transplant. No possible causes for acute liver injury were identified other than the use of the supplement, which contained N-acetyl-L-tyrosine; 1,3,7-trimenthylxanthine; white willow; and 1-hydroxypholedrine. We found no previous reports in the literature of acute liver failure associated with those particular substances. This manuscript is compliant with the Helsinki Congress and the Istanbul Declaration.

An educational intervention improved knowledge of dietary supplements in college students

BACKGROUND

We have previously reported on the prevalence of dietary supplements among college students; it was deduced that their intake of supplements increased according to their grade (i.e., 13.1% in the first grade to 20.5% in the sixth grade). We also reported that some students had experienced adverse events in Japan due to their intake of these supplements. However, awareness of dietary supplements among college students remains limited, even among pharmaceutical students. Being appropriately educated about them is important for pharmaceutical students, both for themselves as well as for their future careers as pharmacists.

METHODS

We conducted a lecture-based educational intervention about dietary supplements on 328 college students in Japan-184 from pharmaceutical science and 144 from environmental science or food and life science disciplines. The purpose of this study was to evaluate the effects of an educational intervention on college students' understanding of dietary supplements. The intervention involved a lecture that covered the quality of dietary supplements, how they differed from drugs, and a summary of their adverse events. The lecture was evaluated using a 14-question questionnaire. We then compared the pre- and post-intervention responses to the same questionnaire using a Wilcoxon signed-rank test. The questions were assessed using a Likert scale that ranged from "strongly agree" to "strongly disagree"; the latter being the preferred answer.

RESULTS

Before the intervention had taken place, the students' understanding of dietary supplements was shown to be deficient. Conversely, post-intervention, their knowledge levels had significantly improved, especially concerning agreement on whether "Dietary supplements are safe because they are just food items". Pre-intervention, 2.7% strongly agreed and 37.5% agreed; post-intervention, 1.2% strongly agreed and 15.6% agreed. On whether "Dietary supplements made from natural ingredients or herbs are safe", at the pre-intervention stage 2.8% strongly agreed and 44.0% agreed and post-intervention, 2.2% strongly agreed and 16.9% agreed. On whether "Dietary supplements made from food items are safe", 4.0% strongly agreed and 43.6% agreed pre-intervention and 0.9% strongly agreed and 16.6% agreed post-intervention. Despite there being a greater number of pharmaceutical students who had a correct understanding of dietary supplements before the intervention, these students still showed improvement after the lecture.

CONCLUSION

An intervention in the form of a single educational lecture has the capacity to improve college students' understanding of dietary supplements. It is important for pharmacists to be appropriately educated about dietary supplements when they consult with patients. We will evaluate the long-term effects of the intervention on the alumni (pharmacists) in a subsequent study.

Signatures in drug-induced liver injury

PURPOSE OF REVIEW

Drug-induced liver injury (DILI) can be induced by a myriad of drugs. Assessing whether the patient has DILI and assessing which drug is the most likely culprit are challenging. There has been too little attention paid to the concept that certain drugs appear to have unique clinical features or 'phenotypes'.

RECENT FINDINGS

Several case series of DILI because of various drugs have been published, and analysis of these case series points to the fact that individual drugs have characteristic DILI signatures. These clinical phenotypes can be characterized by latency, biochemical features (R-value), as well as clinical symptoms and signs. Several drugs, including isoniazid, amoxicillin-clavulanic acid, anabolic steroids, β-interferon and others, have highly unique clinical features. Such unique properties may be able to be used to improve adjudication processes.

SUMMARY

Individual drugs have unique clinical DILI phenotypes or signatures. Furthermore, these may be able to be used to improve adjudication.

A Systematic Review of the Effect of Dietary Supplements on Cognitive Performance in Healthy Young Adults and Military Personnel

Intake of dietary supplements has increased, despite evidence that some of these have adverse side effects and uncertainty about their effectiveness. This systematic review examined the evidence for the cognitive benefits of a wide range of dietary supplements in healthy young adult samples; the aim was to identify if any might be useful for optimising cognitive performance during deployment in military personnel. Searches were conducted in 9 databases and 13 grey literature repositories for relevant studies published between January 2000 and June 2017. Eligible studies recruited healthy young adults (18-35 years), administered a legal dietary supplement, included a comparison control group, and assessed cognitive outcome(s). Thirty-seven of 394 identified studies met inclusion criteria and were included for synthesis. Most research was deemed of low quality (72.97%; SIGN50 guidelines), highlighting the need for sound empirical research in this area. Nonetheless, we suggest that tyrosine or caffeine could be used in healthy young adults in a military context to enhance cognitive performance when personnel are sleep-deprived. Caffeine also has the potential benefit of improving vigilance and attention during sustained operations offering little opportunity for sleep. Inconsistent findings and methodological limitations preclude firm recommendations about the use of other specific dietary supplements.

Factors Related to Disclosure and Nondisclosure of Dietary Supplements in Primary Care, Integrative Medicine, and Naturopathic Medicine

Background:

Patients infrequently disclose use of dietary supplements to providers. Little is known about factors that motivate patients to disclose supplement use. The study aimed to identify reported factors motivating patients’ disclosure and nondisclosure of dietary supplement use and explore differences based on type of supplement and provider practice.

Methods:

Mixed methods study combining qualitative content analysis of semi-structured interviews with statistical analyses to assess differences in identified factors by provider practice type and supplement type. Seventy-eight English-speaking patients who reported taking 466 dietary supplements in the previous 30 days were recruited from primary care and Complementary and Alternative Medicine (CAM), and Integrative Medicine (IM) offices in Southern California.

Results:

We identified nine themes related to disclosure and nine related to nondisclosure of dietary supplement use. Major themes were features of the office visit, circumstances in patient health and medical care, and provider/patient characteristics. The most commonly raised theme promoting disclosure of supplement use was provider inquiry. Patients associate disclosure with having concerns about a supplement but also with annual physical exams and some routine topics of discussion, including self-care, lab results, and new medication prescriptions. Themes related to nondisclosure included lack of provider inquiry, features of the office visit, such as supplements being unrelated to the visit purpose, and patients’ convictions that supplements are safe or not important to discuss. Themes did not vary by supplement type. Primary care patients were more likely than CAM/IM patients to attribute nondisclosure to convictions that supplements were beneficial, not worth mentioning, or equivalent to food (p ≤ 0.001).

Conclusions:

When providers fail to ask directly about dietary supplement use, disclosure is often an impromptu decision that is driven by the content of provider-patient interactions. Ensuring disclosure of dietary supplement use to prevent potential drug-supplement interactions or adverse health outcomes likely requires consistent, proactive provider queries about supplement use.

Prevalence of Dietary Supplement Use and Associated Factors Among College Students in the United Arab Emirates

The use of dietary supplements (DS) is increasing worldwide, however, there are limited studies examining the characteristics of people who take supplements in the United Arab Emirates. To examine the use of DS and their association with sociodemographic/lifestyle factors among college students in the UAE. A cross-sectional study conducted on 452 (18 to 24 years) college students (247 females and 205 males). A self-administered questionnaire that included sociodemographic and lifestyle characteristics, DS use, attitudes, and behavior was used. The prevalence of DS users was 35.6%. Dietary supplement use was significantly more among males than females (P = 0.008). The males preferred protein supplements (29.4%), while females consumed multivitamin and mineral supplements. Dietary supplement use was related to physical activity and the existence of a health problem. Males took DS for medical needs and to increase their muscle mass while females took them for medical needs (P = 0.001). While there a was significant difference between DS users and non-users related to knowledge (P = 0.000). The majority of DS users agreed that supplements are essential for health (68.3%) and only 39.8% agreed it was safe to use. Dietary supplement users source of information was health care providers (30.5%) followed by social media (22.2%). The prevalence of supplement use among college students was moderate among college students in the UAE. The results draw the attention for increasing public awareness about the DS appropriate use and safety from reliable sources so they could make more informed choices.

Pharmacological profiles of compounds in preworkout supplements ("boosters")

Preworkout supplements ("boosters") are used to enhance physical and mental performance during workouts. These products may contain various chemical substances with undefined pharmacological activity. We investigated whether substances that are contained in commercially available athletic multiple-ingredient preworkout supplements exert amphetamine-type activity at norepinephrine, dopamine, and serotonin transporters (NET, DAT, and SERT, respectively). We assessed the in vitro monoamine transporter inhibition potencies of the substances using human embryonic kidney 293 cells that expressed the human NET, DAT, and SERT. The phenethylamines β-phenethylamine, N-methylphenethylamine, β-methylphenethylamine, N-benzylphenethylamine, N-methyl-β-methylphenethylamine, and methylsynephrine inhibited the NET and less potently the DAT similarly to D-amphetamine. β-phenethylamine was the most potent, with IC₅₀ values of 0.05 and 1.8 μM at the NET and DAT, respectively. These IC₅₀ values were comparable to D-amphetamine (IC₅₀ = 0.09 and 1.3 μM, respectively). The alkylamines 1,3-dimethylbutylamine and 1,3-dimethylamylamine blocked the NET but not the DAT. Most of the phenethylamines interacted with trace amine-associated receptor 1, serotonin 5-hydroxytryptamine-1A receptor, and adrenergic α_1A and α_2A receptors at submicromolar concentrations. None of the compounds blocked the SERT. In conclusion, products that are used by athletes may contain substances with mainly noradrenergic amphetamine-type properties.

[Current Problems Associated with Overseas Health Products]

In recent years, consumer interest in health and health foods (e.g., dietary supplements) has increased, and the types of and market for health foods have also expanded rapidly. The safety of health foods is a significant concern in many countries. Numerous adverse events associated with the consumption of health foods have been reported. There are cases that have resulted in serious liver failure, renal failure, and death in other countries. These products may contain undeclared medical ingredients and toxic chemical compounds that are illegally and intentionally added or contain natural plant toxins. Products containing high levels of heavy metals have also been reported to cause such adverse events. Some products remain on the market, even after regulatory agencies alert consumers and issue warnings to their sellers. Moreover, because people can buy health foods from sources overseas via the Internet, adverse effects associated with the use of such products remain a concern. Two cases of adverse events were reported in Japanese individuals who purchased "OxyElite Pro" products imported privately. They are advertised as weight-loss and muscle-building products and have been associated with many cases of liver failure and hepatitis in the USA. In this paper, regulatory systems and adverse events associated with the use of health foods in other countries are discussed.

Investigation and Comparison of Nutritional Supplement Use, Knowledge, and Attitudes in Medical and Non-Medical Students in China

The objective of this study is to investigate and compare the prevalence, knowledge, and attitudes of Chinese university students with respect to nutritional supplements. We conducted a cross-sectional study in several universities around China from January to December 2017, and enrolled a total of 8752 students. Of these, 4252 were medical students and 4500 were non-medical students. The use of nutritional supplements was reported by 58.9% in universities students, with a higher rate for medical students as compared to non-medical students. It was found 24.2% of participants had taken supplements in the past year. Medical students had a higher level of knowledge on nutritional supplements than non-medical students (p < 0.001). The most commonly used nutritional supplements were vitamin C, calcium, and vitamin B. Gender (p < 0.001), household income (p < 0.001), and health status (p < 0.001) were related to the nutritional supplement use after adjustment for related factors. In conclusion, in China, nutritional supplement use was found to be more common in medical students than those studying other disciplines, and was associated with sex, income, and health status. The attitude towards nutritional supplements by medical students was positive. Students’ knowledge levels about nutritional supplements need to be improved

Making Decisions About Supplement Use

The use of dietary supplements is widespread among athletes in all sports and at all levels of competition, as it is in the general population. For the athlete training at the limits of what is sustainable, or for those seeking a shortcut to achieving their aims, supplements offer the prospect of bridging the gap between success and failure. Surveys show, however, that this is often not an informed choice and that the knowledge level among consumers is often low and that they are often influenced in their decisions by individuals with an equally inadequate understanding of the issues at stake. Supplement use may do more harm than good, unless it is based on a sound analysis of the evidence. Where a deficiency of an essential nutrient has been established by appropriate investigations, supplementation can provide a rapid and effective correction of the problem. Supplements can also provide a convenient and time-efficient solution to achieving the necessary intake of key nutrients such as protein and carbohydrate. Athletes contemplating the use of supplements should consider the potential for both positive and negative outcomes. Some ergogenic supplements may be of benefit to some athletes in some specific contexts, but many are less effective than is claimed. Some may be harmful to health of performance and some may contain agents prohibited by anti-doping regulations. Athletes should make informed choices that maximize the benefits while minimizing the risks.

The Prevalence of Dietary Supplement Use among College Students: A Nationwide Survey in Japan

To clarify the prevalence of dietary supplement use among college students, we conducted Internet-based nationwide questionnaire surveys with 157,595 Japanese college students aged between 18 to 24 years old who were registrants of Macromill Inc. (Tokyo, Japan). Among the 9066 respondents (response rate 5.8%), 16.8% were currently using dietary supplements. The prevalence of dietary supplement use did not differ significantly between males (17.1%) and females (16.7%). However, it increased according to their grade (13.1% to 20.5%), and it was higher in medical and pharmaceutical college students (22.0%) compared to others (16.7%). The main purpose of dietary supplement use was for the health benefits in both males and females. Other reasons were to build muscle in males, and as a beauty supplement and for weight loss in females. According to the purpose of dietary supplement use, the most commonly-used dietary supplements were vitamin/mineral supplements in both males and females, then protein and weight loss supplements in males and females, respectively. Although most students obtained information about dietary supplements via the Internet, they typically purchased the supplements from drug stores. Of the students surveyed, 7.5% who were currently using or used to use dietary supplements experienced adverse effects, with no significant difference between genders (8.8% in male, 7.0% in female). In conclusion, the prevalence of dietary supplement use increased with grade among college students in Japan. Some of them experienced adverse effects. Education may be important to prevent adverse effects resulting from supplement use in college.

Adverse Effects of Nutraceuticals and Dietary Supplements

Over 70% of Americans take some form of dietary supplement every day, and the supplement industry is currently big business, with a gross of over $28 billion. However, unlike either foods or drugs, supplements do not need to be registered or approved by the US Food and Drug Administration (FDA) prior to production or sales. Under the Dietary Supplement Health and Education Act of 1994, the FDA is restricted to adverse report monitoring postmarketing. Despite widespread consumption, there is limited evidence of health benefits related to nutraceutical or supplement use in well-nourished adults. In contrast, a small number of these products have the potential to produce significant toxicity. In addition, patients often do not disclose supplement use to their physicians. Therefore, the risk of adverse drug-supplement interactions is significant. An overview of the major supplement and nutraceutical classes is presented here, together with known toxic effects and the potential for drug interactions.

Safety assessment of the dietary supplement OxyELITE™ Pro (New Formula) in inbred and outbred mouse strains

Herbal dietary supplements have gained wide acceptance as alternatives to conventional therapeutic agents despite concerns regarding their efficacy and safety. In 2013, a spate of severe liver injuries across the United States was linked to the dietary supplement OxyELITE Pro-New Formula (OEP-NF), a multi-ingredient product marketed for weight loss and exercise performance enhancement. The principal goal of this study was to assess the hepatotoxic potential of OEP-NF in outbred and inbred mouse models. In an acute toxicity study, significant mortality was observed after administering 10X and 3X mouse-equivalent doses (MED) of OEP-NF, respectively. Increases in liver/body weight ratio, ALT and AST were observed in female B6C3F₁ mice after gavaging 2X and 1.5X MED of OEP-NF. Similar findings were observed in a 90-day feeding study. These alterations were paralleled by altered expression of gene- and microRNA-signatures of hepatotoxicity, including Cd36, Nqo1, Aldoa, Txnrd1, Scd1 and Ccng1, as well as miR-192, miR-193a and miR-125b and were most pronounced in female B6C3F₁ mice. Body weight loss, observed at week 1, was followed by weight gain throughout the feeding studies. These findings bolster safety and efficacy concerns for OEP-NF, and argue strongly for implementation of pre-market toxicity studies within the dietary supplement industry.