Biblioteca de Ingredientes de Suplementos
Cada página de ingrediente cubre qué es, cómo funciona en el cuerpo, el rango de dosis utilizado en ensayos clínicos, efectos secundarios e interacciones, y qué productos en el mercado lo proporcionan en una dosis efectiva.
Alpha-GPC
Alpha-GPC is a choline compound used both as a nootropic and, in Europe, as a prescription treatment for cognitive decline after stroke. It has better human trial support than most nootropic ingredients, including a 2024 randomised trial in mild cognitive impairment. Its use in pre-workouts for power output rests on a much smaller literature.
Alpha-Lipoic Acid
Alpha-lipoic acid has a clinical record most supplement ingredients do not: a named series of randomised trials, ALADIN, SYDNEY, ORPIL and NATHAN, testing it in diabetic peripheral neuropathy. It is a prescription treatment for that indication in Germany. Its use in general antioxidant and weight products is a long way from the evidence that gives it credibility.
Ashwagandha
Ashwagandha is an adaptogenic herb used in Ayurvedic medicine for over 3,000 years. Modern clinical trials show it helps the body manage cortisol, supports sleep quality, and modestly improves strength output. The most studied form is KSM-66, a standardised root extract.
Bacopa Monnieri
Bacopa is one of the better-supported nootropic ingredients in the catalogue, and one of the slowest. Trials that show an effect on memory almost all run twelve weeks, because the effect does not appear before about eight. Anyone judging it on a two-week trial will conclude it does nothing, which is a formulation and expectation problem rather than an evidence problem.
Berberine
Berberine is an alkaloid from goldenseal, barberry, and several other plants. It has emerged as the most credible non-prescription compound for blood-sugar and metabolic-health support — multiple trials show effects comparable in magnitude to metformin in pre-diabetic and type-2 diabetic populations.
Beta-Sitosterol
Beta-sitosterol is a plant sterol with a better-than-expected record in benign prostatic hyperplasia. A Cochrane review pooling four randomised double-blind trials in 519 men found an improvement of about 4.9 points on the International Prostate Symptom Score, alongside improved peak urine flow. It does not shrink the prostate, which is worth knowing before buying it.
Biotin
Biotin is in almost every hair, skin and nail product on the market, at doses hundreds of times the adequate intake. The evidence for that use in people who are not deficient is close to absent, and there is a real, documented harm that has nothing to do with the hair: high-dose biotin interferes with common laboratory immunoassays, including troponin, and the FDA has issued a safety communication about it.
Bitter Melon
Bitter melon is a staple of blood-sugar formulas, and the meta-analyses on it disagree with each other in an instructive way. Earlier reviews found glycaemic improvement on low-quality evidence; a 2024 meta-analysis of nine randomised trials in 414 patients found no significant effect on fasting glucose or HbA1c and concluded the metabolic effect cannot be determined from the available evidence.
Caffeine
Caffeine is the most reliably effective ingredient in this entire library, and the one most likely to be hidden. Products list it as guarana, green coffee bean or a proprietary blend, and stacking two or three of those is how people end up well past the 400 mg a day that regulators consider safe without realising it.
Chromium Picolinate
Chromium is a trace mineral that appears in most blood-sugar and appetite formulas we review, usually as the picolinate salt. The evidence is a good example of statistically detectable but clinically small: meta-analyses find modest reductions in fasting glucose and HbA1c in people with diabetes, and the NIH assessment is explicit that the clinical significance of that is unclear.
Cinnamon
Cinnamon appears throughout the blood-sugar products we review, and which species is in the capsule matters more than the dose. Cassia, the cheap and common one, contains coumarin at levels that can burden the liver at supplement doses. Ceylon cinnamon has negligible coumarin. Most labels say only 'cinnamon'.
CoQ10 (Ubiquinol)
Coenzyme Q10 is an antioxidant fat-soluble compound found in every cell, with the highest concentrations in tissues with high energy demand: heart, kidneys, liver, and brain. Endogenous synthesis declines with age and is suppressed by statins. Supplementation is most credible for statin-induced muscle pain, heart failure adjunct therapy, and migraine prevention.
Creatine Monohydrate
Creatine monohydrate is the most extensively researched sports nutrition supplement. It increases phosphocreatine stores in muscle, enabling more rapid ATP regeneration during high-intensity exercise. Effects on strength, power, and lean mass are well documented across age groups.
Curcumin
Curcumin is the most-studied bioactive compound from turmeric (Curcuma longa). Plain turmeric powder contains only 2–5% curcuminoids and is poorly absorbed — meaningful clinical effects require a specialised delivery format (phytosome, nanoparticle, or piperine-enhanced) at the right dose.
Fenugreek
Fenugreek is the testosterone ingredient with the most credible trial record, which is a low bar cleared honestly. A meta-analysis of clinical trials found a significant effect on total serum testosterone, and a 2024 dose-ranging trial found saliva testosterone rose across doses, most at 1,800 mg. Effect sizes are modest and much of the literature involves branded extracts studied by their manufacturers.
Garcinia Cambogia
Garcinia is one of the most heavily marketed weight-management ingredients and one where the risk-benefit reads badly. The best meta-analysis found a difference of under one kilogram against placebo, with no data beyond twelve weeks. Against that sits a documented association with acute liver injury serious enough for the NIH LiverTox database to carry an entry on it.
Ginger
Ginger's strongest evidence is for nausea, where it is genuinely effective, and its weakest is for the joint indication it is most often sold for. A double-blind randomised trial of one gram a day in knee osteoarthritis found no improvement in pain, symptoms or quality of life, while broader meta-analyses of Zingiberaceae extracts do find a pain effect. Those two results are both real and worth stating together.
Ginkgo Biloba
Ginkgo is unusual among herbal ingredients in that one specific standardised extract, EGb 761, has been through large randomised trials at a consistent dose. That evidence supports use in existing cognitive impairment rather than enhancement in healthy people, a distinction most supplement labelling ignores.
Glucosamine Sulfate
Glucosamine sulfate is the most-studied form of glucosamine for joint health. The clinical trial evidence is form-specific: glucosamine sulfate at 1,500 mg/day shows consistent modest benefit for knee osteoarthritis, while the more common (and cheaper) glucosamine hydrochloride form does not. This distinction explains why so many trials and consumers report different outcomes.
Green Tea Extract (EGCG)
Green tea extract is the backbone of most thermogenic products we review, standardised to EGCG, its principal catechin. Effects on body weight in trials are real but small, and the more important thing to understand before buying is the safety ceiling: concentrated extracts have a documented association with liver injury that brewed green tea does not.
Horny Goat Weed (Epimedium)
Epimedium is in most male-performance formulas on the strength of icariin, a flavonoid that genuinely inhibits PDE5, the same enzyme sildenafil targets. The honest framing is that this is a real mechanism at a very different potency: laboratory work puts icariin's inhibition well below sildenafil's, and human trials of the herb are close to non-existent.
Hydrolyzed Collagen Peptides
Hydrolyzed collagen peptides are short chains of amino acids derived from animal collagen (bovine, marine, or porcine). The hydrolysis process breaks the long collagen protein into 2–5 kDa peptides that are absorbed intact and circulate in the body, where some appear to signal collagen-producing cells (fibroblasts, chondrocytes) to synthesise more endogenous collagen.
L-Arginine
L-arginine is a conditionally essential amino acid and the direct substrate the body uses to make nitric oxide. It is the most common ingredient in the male-performance and pre-workout products we review, on the reasoning that more nitric oxide means better blood flow. The trial evidence supports a modest effect on erectile function and blood pressure, and much less than the marketing implies for pumps and performance.
L-Carnitine
L-carnitine transports fatty acids into mitochondria, which is why it is sold for fat metabolism. The meta-analyses find a real but small effect on body weight, around 1.2 kg across 37 randomised trials. Its better-supported uses are less advertised: male fertility, where it improves sperm parameters, and cardiovascular secondary prevention.
L-Theanine
L-theanine is an amino acid found almost exclusively in tea leaves. It produces a state of calm focus by promoting alpha-wave brain activity without sedation — the same neurological signature seen during meditation. It is the most-studied non-prescription compound for daytime calm and is frequently paired with caffeine to smooth out the stimulant's edge.
MSM (Methylsulfonylmethane)
MSM is a sulfur compound found in nearly every joint formula, usually alongside glucosamine and chondroitin. The trial evidence is small in both trial count and effect size, and it is inconsistent: a 12-week trial at 3.375 g/day improved WOMAC function and total scores, while an 8-week trial at 3 g/day in 180 people found no significant improvement.
Maca
Maca is a Peruvian root vegetable sold across libido, energy and fertility products. Its most interesting finding is a negative one: the trials that show an effect on sexual desire also show that testosterone and oestradiol do not move. Whatever maca does, it does not do it hormonally, which makes the testosterone-booster positioning it is often given straightforwardly wrong.
Magnesium Glycinate
Magnesium glycinate is a chelated form of magnesium bound to the amino acid glycine. It is the form most often recommended for sleep, stress, and muscle relaxation because it is highly bioavailable and far gentler on the gut than magnesium oxide or citrate at equivalent elemental doses.
Omega-3 (EPA + DHA)
EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) are the two long-chain omega-3 fatty acids responsible for nearly all the health benefits attributed to fish oil. Plant-derived ALA (alpha-linolenic acid) converts to EPA and DHA at very low rates in humans, so direct EPA/DHA supplementation is far more effective than flax or chia for clinical endpoints.
Panax Ginseng
Panax ginseng is the ginseng with the trial record; it should not be confused with Siberian ginseng, which is an unrelated plant. Its most consistent finding is on fatigue, particularly mental fatigue. For erectile function the picture is split: a Cochrane review found the effect trivial against placebo, while a meta-analysis restricted to red ginseng found a significant effect in trials of low methodological quality.
Rhodiola Rosea
Rhodiola is the adaptogen with the most usable clinical record for fatigue specifically, built largely around one standardised extract, SHR-5. Unlike most of this category, its effects show up quickly, within days to a couple of weeks, which makes it easier to evaluate honestly than ingredients that require a three-month commitment.
Saw Palmetto
Saw palmetto is the lipidic extract of the Serenoa repens berry. It is the most-used phytotherapeutic for benign prostatic hyperplasia (BPH) in Europe, with over 50 published clinical trials. Standardised lipid extracts (the form used in clinical trials) consistently show modest improvements in urinary symptoms and a much gentler side-effect profile than 5-alpha-reductase inhibitors like finasteride.
Selenium
Selenium is an essential trace mineral with an unusually narrow window between requirement and toxicity: the RDA is 55 mcg and the upper limit is 400 mcg, a factor of about seven. It also carries one of the clearest cautionary tales in supplement research, the SELECT trial, which enrolled over 35,000 men to test whether it prevented prostate cancer and found instead a signal for harm.
Tribulus Terrestris
Tribulus is one of the most widely sold testosterone ingredients and one of the least supported. A 2025 systematic review of trials in men graded the certainty of evidence as very low and could neither support nor refute its use. Where trials do report a sexual-function benefit, it tends to appear without a matching change in testosterone, which points away from the hormonal story printed on most labels.
Vitamin C
Vitamin C is in a large share of the catalogue, usually at doses far above the 75-90 mg daily requirement. Its best-established supplemental effect is unglamorous: taken regularly it does not stop you catching a cold, but it shortens and softens one slightly. Absorption falls off sharply above about 400 mg in a single dose, which makes the 1,000 mg tablet mostly a well-marketed way to make expensive urine.
Vitamin D3 (Cholecalciferol)
Vitamin D3 is the form of vitamin D produced by skin exposure to sunlight and the most bioactive supplemental form. It functions as a hormone precursor: the body converts it via the liver and kidneys into calcitriol, which acts on receptors in nearly every tissue. Adequate vitamin D status is independently associated with better immune function, bone density, and metabolic health.
Zinc
Zinc is an essential trace mineral involved in over 300 enzymatic reactions. It is particularly critical for immune function, wound healing, taste and smell perception, and male reproductive health. Mild deficiency is more common than people realise — vegetarians, older adults, and people with chronic GI conditions often run low without obvious symptoms.