Slim Metrix Ingredients: All Ten, and the Dose Each One’s Research Used

The one ingredient on this label where a reader can do the whole comparison without leaving the page. Chromium picolinate is the most-studied form of the mineral, and the question it has been asked for thirty years is whether it helps with body weight and glucose handling.

The answer from the 2013 Cochrane review of chromium picolinate is a qualified no. Pooling doses of 200, 400, 500 and 1,000 mcg a day it found a mean difference of 1.1 kg after 12 to 16 weeks, which its own authors described as of debatable clinical relevance, on low-quality evidence. a 2013 meta-analysis in Obesity Reviews reached a similar place, and a 2019 meta-analysis in Clinical Obesity looked at anthropometric measures specifically, and a 2024 dose-response meta-analysis of chromium and body composition ran the dose-response version of the same question in people with type 2 diabetes.

On glucose, a 2011 trial in Endocrine Practice ran 500 mcg and 1,000 mcg daily in people at risk of diabetes and neither arm separated from placebo on the primary measures. a 2017 pilot trial in the Journal of Dietary Supplements used 1,000 mcg and 600 mcg arms in a pilot. Against all of that, 50 mcg is a nutritional amount rather than a trial amount, and it is worth reading as a mineral top-up in the formula rather than as the active lever.

The second printed figure, and a sensible one. Zinc gluconate is a common, well-absorbed form, and 5.5 mg is roughly half an adult daily requirement, which makes it a top-up rather than an intervention.

The glycaemic literature is larger than most people expect. a 2019 meta-analysis in the American Journal of Clinical Nutrition pooled 32 placebo-controlled interventions across 1,700 participants and found consistent reductions in fasting glucose, post-prandial glucose and glycated haemoglobin. a 2013 meta-analysis of zinc and glycaemic control and a 2024 dose-response meta-analysis of zinc supplementation cover the same ground with different methods.

The dose most relevant as a comparison is the 30 mg a day used for 14 weeks in a 2003 controlled trial of low-level zinc supplementation, chosen because it sits under the US upper intake level of 40 mg. That trial matters for a second reason: high supplemental zinc interferes with copper, which a 1990 review of zinc toxicity in the American Journal of Clinical Nutrition documents at 100 to 300 mg a day and a 2001 metabolic-unit study of zinc and copper examines at the other end of the range. At 5.5 mg none of that is in play, which is exactly why this is a reasonable amount to put in a daily capsule.

A standardisation without a weight beside it. The percentages describe the material precisely: half of it is epigallocatechin gallate and four fifths of it is catechins of one kind or another. What a capsule contains depends on how many milligrams of that material go in, which is the seller’s to state.

The comparison figures are clear enough. a 2017 meta-analysis of EGCG and energy expenditure reviewed the energy-expenditure work and put a measurable change around 300 mg of EGCG. a 2007 catechin trial in Obesity ran 583 mg of catechins a day against a 96 mg control for twelve weeks and reported a reduction in body fat. a 2016 randomised trial in Clinical Nutrition went to 856.8 mg of EGCG daily in women with central obesity and measured weight and waist changes over the same span.

The sober counterweight is the 2012 Cochrane review of green tea for weight loss, whose pooled estimate across the green tea weight-loss trials was small and not clinically important. The honest summary is that green tea catechins do something measurable to energy expenditure at doses in the hundreds of milligrams, and that what it adds up to over months is modest.

The most pharmacologically active name on this label, and the one that most deserves a conversation with a clinician before the first capsule.

Its metabolic evidence is genuinely strong for a botanical. a 2021 meta-analysis of berberine in type 2 diabetes pooled randomised trials in type 2 diabetes and found improvements across the glycaemic measures; a 2015 meta-analysis in the Journal of Ethnopharmacology covered diabetes, lipids and blood pressure together; a 2018 meta-analysis of berberine and blood lipids looked at dyslipidaemia specifically. a 2020 systematic review of berberine and body weight is the systematic review that addresses body weight directly.

Dose is where the comparison bites. a 2024 meta-analysis that records the doses berberine trials use records the commonest regimen across the trials as 0.9 to 1.5 grams a day, usually split across meals because of how berberine behaves in the gut. A once-daily capsule carrying an unstated weight of 97% material is a different proposition from that, and the 97% describes purity rather than quantity.

Berberine is also the ingredient here most likely to interact with a prescription, because it affects the pathways that clear many common drugs and lowers blood glucose in its own right. a 2019 meta-analysis of the berberine and silymarin pairing and a 2022 meta-analysis of berberine with silymarin on liver enzymes cover the berberine and silymarin pairing, which this formula happens to contain.

The first of the six blend members, and the one where the blend ceiling is least damaging. a 2019 dose-response meta-analysis in Obesity Reviews ran a dose-response meta-analysis across the obesity measures and found its signal on weight and BMI specifically in trials dosing under 500 mg a day and running three months or longer.

That matters because a share of 276 mg is not automatically outside the studied range, which is unusual among blend ingredients. a 2014 meta-analysis of eleven resveratrol trials pooled eleven randomised trials on glucose control and a 2021 umbrella review of resveratrol meta-analyses is the umbrella review across the metabolic conditions.

The catch is absorption. a 2011 review of resveratrol bioavailability sets out why resveratrol reaches the bloodstream in such small proportions that oral dosing is an inefficient way to deliver it, and a 2020 review of resveratrol's adverse effects reviews what happens at the upper end. A modest share of a blend is a modest intervention.

Standardised to 80% silymarin, which is the conventional specification, and then placed inside a total that six ingredients share.

The glycaemic trials used far more. a 2006 randomised trial in Phytotherapy Research gave 200 mg three times a day, 600 mg in total, for four months; a 2018 triple-blinded trial in Phytomedicine used 140 mg three times a day, 420 mg in total, for 45 days. Both reported improvements in glycaemic indices in people with type 2 diabetes.

The ceiling case is the 2012 SyNCH trial in JAMA, the JAMA trial that ran 420 mg and 700 mg three times daily for 24 weeks in chronic hepatitis C and found that neither higher-than-customary dose beat placebo on liver enzymes. a 2017 review of silybin chemistry and bioavailability explains the absorption problem underneath all of it. A share of 276 mg is an order of magnitude below any of those numbers.

The appetite ingredient, and the one with the most specific human dose attached to it. a 2014 crossover trial in Appetite gave capsaicin 2.56 mg with every meal, which is about a gram of red chilli pepper, and measured a rise in the sensation of fullness in energy balance and a fall in the desire to eat after dinner in negative energy balance.

a 2018 meta-analysis of capsaicin and capsiate in human studies pooled the human studies of capsaicin and its non-pungent analogues and found effects on energy expenditure and respiratory quotient that the authors considered supportive.

Two things follow. The trial dose is small, which means a share of a 276 mg blend could plausibly reach it. And the trial dose was given with every meal rather than once in the morning, which a single daily capsule cannot reproduce.

Standardised to 8% ginsenosides, which is a respectable specification for the material. a 2014 meta-analysis of ginseng and glycaemic control pooled sixteen randomised trials of the genus and found fasting blood glucose fell by 0.31 mmol/L against control, a real but small effect.

a 2013 trial of Korean red ginseng in overweight adults is the trial closest to this product’s audience: six grams a day of Korean red ginseng rootlets for twelve weeks in non-diabetic overweight and obese adults.

Six grams is more than twenty times the entire blend. Whatever ginseng is doing in this capsule, it is not reproducing that trial, and the sensible reading is that it is present as a traditional companion to the other botanicals rather than as an active dose.

Standardised to 2% corosolic acid, the constituent most of the research concerns. a 2012 review of banaba and corosolic acid is the review that covers the field, and it describes work across animal models, human subjects and in vitro systems using water-soluble leaf extracts, corosolic acid-standardised extracts and purified corosolic acid.

The review notes that pure corosolic acid has been reported to lower blood sugar within an hour in human subjects, which is the most concrete human finding in this ingredient’s file.

At 2% standardisation, a share of a 276 mg blend delivers a small quantity of corosolic acid by any division. The honest position is that banaba has a plausible mechanism, a thin human evidence base, and no agreed effective dose to compare a blend share against.

The ingredient that is on one piece of the vendor’s artwork and absent from the other, and which the seller’s own list confirms belongs inside the blend.

a 2017 meta-analysis of alpha-lipoic acid and weight pooled randomised trials of alpha lipoic acid and weight and found small reductions, with meta-regression showing no relationship between dose and the change in BMI or weight. a 2018 systematic review of alpha-lipoic acid in obesity reached comparable conclusions and put the safe intake at up to 1,200 mg a day.

That upper figure is the useful one for a blend comparison. Trials in this ingredient run to four figures in milligrams; a share of 276 mg across six ingredients is two orders of magnitude below the ceiling those reviews describe.