The supplement industry has exploded in recent decades, growing from about 4,000 products in 1994 to well over 80,000–100,000 today (1,2). In the U.S. alone, the market now exceeds $65 billion annually, and worldwide it is approaching $200 billion (1,2). Despite this growth, supplements are not required to prove safety or effectiveness before being sold – unlike pharmaceuticals – so they bypass pre-market approval for safety or efficacy (3). This regulatory gap leaves consumers exposed to both misinformation and potential harm (4).
Among the most serious risks are organ injuries. Liver damage is the most frequently reported, with more than 75 individual herbs/supplements implicated in liver injury identified in the literature. Common culprits include green tea extract, Hydroxycut weight-loss blends, and other herbs (5). Even botanicals often viewed as benign, such as turmeric or ashwagandha, have been linked to dozens of liver injury cases (6). Muscle injury is another danger: stimulant-heavy pre-workout products have caused cases of rhabdomyolysis, a severe muscle breakdown that can lead to kidney failure (7). The kidneys themselves can also be directly harmed by contaminated supplements. A striking example occurred in Japan, where tainted red yeast rice cholesterol pills (beni-koji) led to over 500 hospitalizations and around 80 deaths from acute kidney damage (8). Even seemingly safe nutrients can pose risks – for instance, chronically high doses of vitamin C have been associated with kidney injury (e.g. kidney stone formation) (9), and herbal remedies containing aristolochic acid (found in some traditional botanicals) have caused permanent kidney failure and urinary cancers in users (10).
Another hidden risk comes from interactions between supplements and medications. Many supplements act on the same pathways as drugs, unintentionally amplifying or undermining their effects. For instance, natural blood-thinners like garlic, ginkgo, nattokinase, or fish oil can all dangerously increase bleeding risk in patients on the anticoagulant warfarin (11). Red yeast rice contains monacolin K (chemically identical to lovastatin) and essentially duplicates the action of a statin – taking both together effectively doubles the dose and heightens the risk of muscle damage or liver injury from excessive statin effect (12). Conversely, St. John’s wort (a popular mood herb) is a potent inducer of drug-metabolizing enzymes, speeding up the clearance of many medications. It can make prescription drugs, such as statins for cholesterol, antidepressants, certain HIV treatments, or oral contraceptives, less effective by sharply reducing their blood levels (13). Indeed, cases have shown St. John’s wort triggering organ transplant rejection and unplanned pregnancies due to these interactions (13).
Long-term risks are also a concern, especially when supplements chronically target key biological pathways. Some nutrients, when taken at high doses, may inadvertently increase the risk of cancer instead of preventing it. For example, large randomized trials found that beta-carotene supplements raised lung cancer rates in smokers by roughly 17% (14). Likewise, extended use of high-dose vitamin E was linked to a significant increase in prostate cancer incidence (about 17% higher in the Vitamin E group of the SELECT trial) (15). At the same time, supplements that stimulate the immune system – such as echinacea or spirulina – have been reported to exacerbate autoimmune conditions (like lupus, multiple sclerosis, or inflammatory myopathies). There are case reports of echinacea and spirulina precipitating flare-ups of diseases such as pemphigus and dermatomyositis in susceptible individuals (16). These findings highlight that what seems beneficial in the short term may cause harm when used chronically or in certain at-risk populations.
Supplements can also interact with each other in ways that produce synergistic effects. Sometimes synergy is positive – as with turmeric and black pepper, where the alkaloid piperine in black pepper boosts curcumin absorption by about 2,000% (17). But synergy can also be harmful. For example, combining multiple stimulants can lead to additive cardiovascular stress, and taking several blood-thinning supplements together multiplies the risk of bleeding. A classic case is the mix of a prescription anticoagulant with herbal and vitamin blood-thinners: one FDA advisory noted that warfarin, ginkgo, aspirin, and vitamin E each have anticoagulant effects – and using them together greatly increases the chance of internal hemorrhage or stroke (18).
A major challenge is that most supplements are never tested in clinical trials, so the majority of products reach consumers without robust evidence of their safety or benefits. What we do know about risks often comes from case reports, medical literature, and adverse event databases, and these are severely underreported overall. For example, the FDA received just 15,000 supplement-related adverse event reports between 2004 and 2013 (19), which is likely less than 2% of the true incidence (FDA analyses estimate over 50,000 supplement adverse events occur each year) (20). This massive underreporting gap underscores why it’s so important to aggregate real-world experiences – it’s the only way to detect patterns of efficacy or harm that would otherwise go unnoticed.
Because most supplements lack strong published data but remain widely used, our focus must shift to ensuring the safety of combinations and user-specific scenarios. This is where OpenHealth comes in. Built by doctors and engineers, OpenHealth helps people navigate the supplement landscape by aggregating user-reported experiences and clinical knowledge, performing deep scientific analyses of biological pathways, and identifying potential risks ranging from organ injury and drug interactions to long-term concerns like cancer or autoimmune triggers. It curates personalized supplement regimens with actionable insights and continuously surfaces the latest scientific literature to keep users informed. With thousands of products on the market and minimal oversight, OpenHealth delivers the rigorous science, accurate data, and personalized guidance needed to make supplement use safer.
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