Supplements for Metabolic Health: What the Evidence Shows (2026 Update)
Only about 12% of American adults have optimal levels of every standard metabolic measure without taking related medicine.1 This article reviews what clinical trials have found for five supplements and these measures, from fasting glucose and triglycerides to blood pressure, and where the evidence is limited. Supplements do not replace medicines, and several can interact with them.
When most people hear "metabolic health," they think about weight. But clinically, metabolic health is often assessed using six measures: fasting blood glucose, triglycerides, HDL cholesterol, blood pressure, waist circumference, and HbA1c. In a 2019 analysis of U.S. national survey data (NHANES 2009–2016) published in Metabolic Syndrome and Related Disorders, 12.2% of adults had optimal levels of all of these measures and were not taking any related medication.1
That means about nine in ten adults either have at least one of these measures outside the optimal range or take medicine for one of them. These measures are used to assess the risk of conditions such as type 2 diabetes and cardiovascular disease.
Lifestyle — diet, exercise, sleep, stress management — remains the foundation. Medicines prescribed for diabetes, blood pressure or cholesterol should not be stopped, reduced, switched or replaced because of a supplement. This article covers five supplements that have been studied for metabolic markers, what their mechanisms are thought to be, what the studies show, how strong the evidence is, and what to ask a prescriber or pharmacist.
What Counts as Metabolic Health?
Before discussing supplements, it's worth looking at how metabolic health is measured. One analysis of national survey data used these optimal thresholds:1
- Fasting blood glucose: <100 mg/dL
- Triglycerides: <150 mg/dL
- HDL cholesterol: >40 mg/dL (men) / >50 mg/dL (women)
- Blood pressure: <120/80 mmHg
- Waist circumference: <40 inches (men) / <35 inches (women)
- HbA1c: <5.7%
Each supplement in this article has been tested in human trials that measured at least one of these markers. Results vary, and many trials are small or short. The evidence labels below are our own plain-language summary of the sources cited, not a clinical grade. These supplements can interact with medicines (see the safety notes) and some can lower blood glucose or blood pressure, so ask a prescriber or pharmacist before combining them with any prescription medicine.
Berberine — The AMPK Activator
Berberine is an isoquinoline alkaloid extracted from plants including Berberis aristata and Coptis chinensis. It has been used in traditional medicine for centuries. Clinical trials have since tested it for blood glucose and blood fats, with promising results that come mostly from small, short trials of limited quality (see below). Berberine is a dietary supplement, not an approved treatment for diabetes, and it must not be used in place of diabetes medicine.
In cell and animal studies, berberine activated AMP-activated protein kinase (AMPK), an enzyme often described as the cell's "master metabolic switch," and increased GLUT4 translocation in muscle cells.3 How much of berberine's effect in people is explained by this mechanism has not been established.
In a 2008 randomized, placebo-controlled trial of 116 people with type 2 diabetes and abnormal blood fats (dyslipidemia), berberine 1.0 g a day for 3 months lowered fasting glucose (7.0 to 5.6 mmol/L), HbA1c (7.5% to 6.6%), triglycerides (2.51 to 1.61 mmol/L) and LDL cholesterol (3.23 to 2.55 mmol/L), and these changes differed significantly from placebo. The only side effect reported was mild to moderate constipation in five participants taking berberine.4
Zhang Y, et al. J Clin Endocrinol Metab. 2008;93(7):2559-2565.A 2012 meta-analysis of 14 randomized trials (1,068 participants) found that berberine plus lifestyle change lowered glucose and blood fats more than lifestyle change alone or with placebo. Compared with oral diabetes drugs including metformin, glipizide and rosiglitazone, berberine did not show significantly better glucose control, and the methodological quality of the trials was generally low.5 A 2022 meta-analysis of 37 trials (3,048 participants) found an average HbA1c reduction of 0.63 percentage points compared with control.6 Neither finding shows that berberine is equivalent to a diabetes medicine.
- Fasting blood glucose: About 0.8 mmol/L (roughly 15 mg/dL) lower on average than control in a meta-analysis of 37 trials in type 2 diabetes6
- HbA1c: About 0.63 percentage points lower than control in the same analysis; study quality in this field is often low5,6
- Triglycerides: Lower in trials; berberine alone lowered triglycerides by about 17 mg/dL on average in a meta-analysis of 41 trials7
- LDL cholesterol: Berberine alone did not lower LDL cholesterol significantly in the same analysis (about 9 mg/dL, not statistically significant), and results varied widely between trials7
- Insulin sensitivity: In the 2008 trial, a clamp measure of insulin sensitivity rose with berberine, but the difference from placebo was not statistically significant4
Dose and Timing
Berberine trials have used different doses, for example 1.0 g a day,4 0.5 g three times a day,8 and 0.3 g twice a day.9 Higher doses have not been shown to work better, so do not exceed the dose on the product label. Berberine is poorly absorbed into the blood, yet it can still affect enzymes in the gut and liver.10 Most trials lasted about 3 months, and long-term data are limited. For a full comparison with metformin, see our article: Berberine vs. Metformin: What the Evidence Shows →
Safety: In healthy volunteers, two weeks of berberine reduced the activity of CYP2D6, CYP2C9 and CYP3A4, liver and gut enzymes that clear many medicines.11 In kidney-transplant recipients taking cyclosporine, berberine raised blood levels of the anti-rejection drug.12 Check with a pharmacist or prescriber before taking berberine if you take any prescription medicine. Berberine can add to the blood-glucose-lowering effect of diabetes medicines, and low blood sugar is the main concern if you also take insulin or a sulfonylurea; do not use berberine in place of a prescribed diabetes medicine, and do not stop or change a medicine because of a supplement. Constipation and other digestive effects were the most commonly reported side effects in trials.4,9 In 2026, life-threatening heart-rhythm problems (torsades de pointes) were reported in a few people taking berberine supplements, some of whom were also taking other supplements or medicines.13,14,15 Avoid berberine during pregnancy and breastfeeding: safety has not been established, and laboratory work found that berberine displaced bilirubin from its carrier protein, a concern for jaundiced newborns, although a later review found conflicting evidence.16,17
Magnesium Glycinate — A Mineral Involved in Insulin Signaling
Magnesium is a cofactor in hundreds of enzymatic reactions.18 Low magnesium inside cells has been linked to reduced insulin-receptor tyrosine-kinase activity and worse insulin resistance.19 In a pooled analysis of 35 cohorts, the highest magnesium intake was associated with a 22% lower risk of type 2 diabetes than the lowest intake.20 Observational findings like this do not prove that taking a supplement lowers risk.
A 2012 review reported that 48% of the US population consumed less than the required amount of magnesium from food in 2005–2006.21 Eating less than the required amount is not the same as being deficient. Magnesium losses through the kidneys are increased in diabetes, and some medicines add to this.22
A randomized, placebo-controlled trial of 198 people with metabolic syndrome and low blood magnesium (hypomagnesemia) gave magnesium chloride solution, equivalent to 382 mg of elemental magnesium, daily for 16 weeks. Changes in blood pressure, fasting glucose and triglycerides were significantly greater than with placebo (systolic pressure -3.6 mmHg, diastolic -5.5 mmHg, fasting glucose -12.4 mg/dL, triglycerides -61.2 mg/dL); the HDL cholesterol change was not statistically significant.23 This trial used magnesium chloride in people with low magnesium levels, not magnesium glycinate.
Rodríguez-Morán M, et al. Adv Chronic Kidney Dis. 2018;25(3):261-266.Which Form of Magnesium?
Magnesium comes in several forms. In a small study in volunteers, magnesium oxide was absorbed poorly (fractional absorption about 4%), while magnesium chloride, lactate and aspartate were absorbed better and about equally well.24 Magnesium glycinate (magnesium bound to the amino acid glycine) was not tested in that study, and we did not find trials comparing glycinate with other forms for blood sugar, blood pressure or digestive tolerance, so claims that it is better absorbed or gentler on the stomach have not been established. Any magnesium supplement can cause diarrhea at higher doses.25
- Fasting glucose and insulin resistance: Small reductions in fasting glucose, fasting insulin and HOMA-IR in a meta-analysis of 26 randomized trials (1,168 participants)20
- Type 2 diabetes with low magnesium: In 63 people with type 2 diabetes and low magnesium who were taking glibenclamide (a sulfonylurea), fasting glucose and HbA1c were lower with magnesium chloride than with placebo after 16 weeks26
- Blood pressure: A meta-analysis of 34 trials (2,028 participants) found that magnesium at a median of 368 mg/day for about 3 months lowered systolic pressure by 2.00 mmHg and diastolic pressure by 1.78 mmHg compared with placebo27
- Triglycerides: Lower than placebo in the metabolic syndrome trial above; HDL cholesterol did not change significantly23
Dose and Timing
The trials above used about 370–380 mg of elemental magnesium a day (a median of 368 mg/day in the blood pressure meta-analysis;27 382 mg/day in the metabolic syndrome trial23). The US upper limit for supplemental magnesium in adults is 350 mg a day, set because larger amounts commonly cause diarrhea; some researchers argue the limit should be re-evaluated.25 Add up the magnesium from every supplement and antacid you take.
Safety: Severe magnesium excess is almost exclusively seen in people with substantially reduced kidney function who take large amounts from supplements, antacids or laxatives, so ask a doctor before using magnesium supplements if you have kidney disease.22 Magnesium can reduce the absorption of some medicines: in a small trial in healthy adults it lowered absorption of levothyroxine (thyroid hormone),28 so ask a pharmacist about timing and interactions if you take thyroid medicine or any other prescription medicine. Magnesium may also lower blood pressure and blood glucose slightly, which may add to the effect of medicines for these conditions. Ask a doctor or pharmacist before use if you are pregnant or breastfeeding. For related background, see: Why You Wake Up at 3am — and What Magnesium Has to Do With It →
CoQ10 (Ubiquinone) — Mitochondrial Energy Currency
Coenzyme Q10 is a fat-soluble compound found in the inner mitochondrial membrane, where it serves as an electron carrier in the oxidative phosphorylation chain — the process by which cells generate ATP from glucose and fatty acids. In plain terms: CoQ10 is the essential link between metabolic fuel and cellular energy output.
Statins lower blood levels of CoQ10 because they block an early step in the pathway that also makes it.29 A meta-analysis of 8 placebo-controlled statin treatment arms found that plasma CoQ10 fell by 0.44 µmol/L on average.30 A 2005 review found insufficient human evidence that statins lower CoQ10 in muscle and other tissues,29 and we did not find reliable evidence that low CoQ10 explains fatigue or impaired glucose metabolism in healthy adults.
A 2026 meta-analysis of 64 randomized trials (3,422 participants with metabolic disorders) found that CoQ10 supplements lowered HbA1c by 0.22 percentage points, fasting glucose by about 10 mg/dL, triglycerides by about 6 mg/dL and total cholesterol by about 5 mg/dL on average compared with control, which are small changes.31 Another 2026 meta-analysis of 39 randomized trials found small reductions in fasting glucose and insulin, a change in HbA1c that was not statistically significant, and rated the certainty of the evidence as very low.32
Zhang Z, et al. J Diabetes Res. 2026;2026(1):e5587445.A 2022 meta-analysis of 26 trials in people with cardiometabolic disorders found that CoQ10 lowered systolic blood pressure by 4.77 mmHg on average (moderate-certainty evidence),33 and a 2025 meta-analysis of 45 trials found a 3.44 mmHg reduction in systolic pressure with no significant effect on diastolic pressure.34 These are small effects, and CoQ10 is not a replacement for blood pressure medicine.
- Fasting glucose: About 10 mg/dL lower on average across 64 trials in metabolic disorders;31 certainty of evidence rated very low in another meta-analysis32
- HbA1c: 0.22 percentage points lower on average in the first analysis,31 and not statistically significant (-0.12%) in the second32
- Blood pressure: Systolic pressure about 3–5 mmHg lower on average in two meta-analyses33,34
- Triglycerides: About 6 mg/dL lower on average31
- Statin users: Statins lower blood CoQ10;30 meta-analyses of CoQ10 for statin muscle symptoms disagree, with one finding no significant benefit35 and another finding improvement36
Dose and Timing
Trials in the meta-analyses above used a range of doses; one dose-response analysis found the largest blood pressure effect at about 100–200 mg a day.33 We did not find reliable evidence that the ubiquinol form works better at lower doses than ubiquinone. CoQ10 is fat-soluble, and labels commonly advise taking it with a meal that contains fat.
Safety: CoQ10 was generally well tolerated in trials; nausea and other digestive complaints have been reported, and in a safety review they were not clearly related to dose.37 CoQ10 may reduce the effect of warfarin in some people: one case report described a weaker warfarin response that returned to normal when CoQ10 was stopped,38 although a small crossover trial of 24 people taking 100 mg/day found no change in INR or warfarin dose.39 If you take warfarin, talk to your prescriber before starting CoQ10. CoQ10 may lower blood pressure and blood sugar slightly, so tell your prescriber if you take medicines for either; one case report linked CoQ10 to insulin autoimmune syndrome with severe low blood sugar.40 For statin users, see our article: CoQ10 and Statins: What the Evidence Shows →
Omega-3 Fatty Acids (EPA/DHA) — Triglycerides
Omega-3 fatty acids — specifically eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) from marine sources — lower blood triglycerides at high doses, which is their best-supported use for metabolic health.41 Kinetic studies in humans show that they reduce the release of triglyceride-carrying VLDL particles from the liver, but the biochemical mechanism in humans remains uncertain.42
Omega-3s have also been studied for inflammation and blood sugar. A 2022 meta-analysis of 46 trials in type 2 diabetes found that omega-3 supplements lowered triglycerides, HbA1c (by 0.19 percentage points) and C-reactive protein, but had no significant effect on fasting blood sugar, insulin resistance or adiponectin.43
The American Heart Association's 2019 Science Advisory concluded that prescription omega-3 products (EPA+DHA or EPA alone) at 4 g/day are an effective and safe option for lowering triglycerides, by 30% or more in people with very high triglycerides (500 mg/dL or above); in that group EPA+DHA products raised LDL cholesterol, while EPA alone did not.41 The REDUCE-IT trial of a prescription EPA drug (icosapent ethyl, 4 g/day) in 8,179 statin-treated people with raised triglycerides and cardiovascular disease or diabetes found fewer cardiovascular events (17.2% vs 22.0%; hazard ratio 0.75), but more hospitalizations for atrial fibrillation or flutter (3.1% vs 2.1%).44 A trial of a 4 g/day EPA+DHA prescription formulation (STRENGTH) found no reduction in cardiovascular events.45 These results apply to prescription products and do not show that over-the-counter fish oil has the same effects.
Bhatt DL, et al. N Engl J Med. 2019;380(1):11-22. | Skulas-Ray AC, et al. Circulation. 2019;140(12):e673-e691.- Triglycerides: 30% or more lower at 4 g/day of prescription EPA+DHA or EPA in people with very high triglycerides41
- Cardiovascular events: 25% lower relative risk with prescription EPA (4 g/day) in REDUCE-IT; no benefit with 4 g/day prescription EPA+DHA in STRENGTH44,45
- C-reactive protein: Lower in a meta-analysis of trials in type 2 diabetes, with no significant effect on adiponectin43
- Blood pressure: Small reductions on average (-1.52/-0.99 mmHg systolic/diastolic) in a meta-analysis of 70 trials, larger in untreated high blood pressure46
Dose and Timing
The AHA advisory notes that a 2002 AHA statement recommended 2–4 g a day of EPA+DHA for lowering elevated triglycerides, and concludes that prescription products at 4 g a day are an effective and safe option for very high triglycerides.41 These are medical uses that should be decided with a prescriber. Check the label for the amount of EPA and DHA per serving, which is often lower than the total oil listed. Taking fish oil with a meal is commonly advised.
Safety: In a 2021 meta-analysis of seven large cardiovascular trials (81,210 participants, mean age 65), marine omega-3 supplements were associated with a higher risk of atrial fibrillation (hazard ratio 1.25), and the risk was greater in trials using more than 1 g a day (hazard ratio 1.49) than in trials using 1 g a day or less (1.12).47 A 2026 meta-analysis of 35 trials found a significant increase only in people at high cardiovascular risk taking more than 1,500 mg a day.48 If you have a heart rhythm condition or heart disease, take a blood thinner such as warfarin, or have surgery planned, talk to a prescriber before taking fish oil, especially above about 1 g a day: a meta-analysis of 11 trials found no overall increase in bleeding with omega-3, but high-dose purified EPA was linked to more bleeding,49 and one case report described a rise in INR after a patient taking warfarin doubled their fish oil dose.50 Fish oil may also lower blood pressure slightly, which may add to the effect of blood pressure medicines.
Chromium + L-Carnitine — Two Compounds Studied for Glucose Control
Chromium and L-carnitine are different compounds that are sometimes sold together. The evidence for each is summarized separately below.
Chromium is an essential trace mineral that has been tested, mostly as chromium picolinate, for glucose control in people with type 2 diabetes. How it might work is not settled. A 2014 meta-analysis of 25 randomized trials found that chromium supplements lowered HbA1c by 0.55 percentage points on average, with better glucose control at more than 200 µg a day; the risk of adverse events did not differ from placebo at usual doses, but long-term benefit and safety remain to be investigated.51 In a Cochrane review of 9 trials in overweight or obese adults, chromium picolinate lowered body weight by about 1.1 kg after 12 to 16 weeks, an effect of debatable clinical relevance, and adverse events were reported in only three studies.52 Rare hypersensitivity reactions, including delayed skin reactions, have been reported with chromium picolinate.53
L-Carnitine is an amino acid derivative that transports long-chain fatty acids across the inner mitochondrial membrane. In a 2024 meta-analysis of 21 randomized trials in type 2 diabetes, each 1 g/day of L-carnitine was associated with a small reduction in HbA1c (0.16 percentage points) and in body mass index (0.37 kg/m², low-certainty evidence), and results varied widely between trials.54
A 1997 randomized trial by Anderson and colleagues in Diabetes assigned 180 people being treated for type 2 diabetes to placebo, 200 µg or 1,000 µg of chromium a day (as chromium picolinate) for four months; participants kept taking their usual medicines. After four months, HbA1c was 8.5% with placebo, 7.5% with 200 µg and 6.6% with 1,000 µg a day, and fasting and 2-hour glucose were lower in the 1,000 µg group.55 This was a single trial from the 1990s; a later meta-analysis found a smaller average HbA1c reduction (0.55 percentage points).51
Anderson RA, et al. Diabetes. 1997;46(11):1786-91.- Chromium — HbA1c: 6.6% on 1,000 µg a day versus 8.5% on placebo after 4 months in one trial in type 2 diabetes;55 about 0.55 percentage points lower on average in a meta-analysis51
- Chromium — insulin: Fasting and 2-hour insulin fell in both chromium groups in the same trial55
- L-Carnitine — HbA1c: About 0.16 percentage points lower per 1 g/day in a meta-analysis of 21 trials in type 2 diabetes, with high variation between trials54
- L-Carnitine — body mass index: About 0.37 kg/m² lower per 1 g/day in the same analysis (low-certainty evidence)54
- Chromium + biotin: In a 90-day trial of 447 people with poorly controlled type 2 diabetes taking oral diabetes medicines, chromium picolinate (600 µg) with biotin lowered HbA1c by 0.54%, a significant difference from placebo; the combination was compared with placebo, not with chromium alone56
Dose and Timing
Chromium doses in the trials above ranged from 200 to 1,000 µg a day, and the meta-analysis found better glucose control at more than 200 µg a day.51,55 The L-carnitine meta-analysis covered doses up to 4 g a day,54 and a systematic review in healthy adults used 1 to 4 g a day for 12 to 24 weeks.57 These compounds have not been tested in combination with berberine or CoQ10.
Safety: In that systematic review, L-carnitine raised fasting blood levels of TMAO, a gut-derived compound thought to promote artery disease; the authors say that long-term effects on heart health need to be studied.57 In a placebo-controlled trial in women taking thyroid hormone (levothyroxine), 2 or 4 g a day of L-carnitine reduced hyperthyroid symptoms, showing that it can counteract thyroid hormone action; people with a thyroid condition or who take thyroid medicine should ask a prescriber before using it.58 Chromium and L-carnitine both lowered blood glucose in trials, and the effect may add to that of diabetes medicines (the main concern is low blood sugar with insulin or a sulfonylurea). Ask a pharmacist or prescriber before use if you take diabetes or thyroid medicine, are pregnant or breastfeeding, or have kidney disease.
Side-by-Side: Mechanisms and Metabolic Targets
| Supplement | Proposed Mechanism | Glucose | Triglycerides | BP | Our evidence summary |
|---|---|---|---|---|---|
| Berberine | AMPK activation in cell and animal studies; effects in people not fully explained | Lower in many small trials | Lower in many trials | No significant effect in one meta-analysis59 | ★★★☆☆ |
| Magnesium Glycinate | Cofactor in insulin signaling; glycinate form not compared with other forms | Small reductions in meta-analysis | Lower in one trial in metabolic syndrome | About 2 mmHg systolic reduction in meta-analysis | ★★★☆☆ |
| CoQ10 | Electron transport in mitochondria; antioxidant | Small reductions; very low certainty in one analysis | About 6 mg/dL lower on average | About 3–5 mmHg systolic reduction in meta-analyses | ★★☆☆☆ |
| Omega-3 (EPA/DHA) | Lower VLDL triglyceride secretion; exact mechanism uncertain | No significant effect on fasting glucose in type 2 diabetes meta-analysis | Lowered at prescription-level doses | About 1.5 mmHg systolic reduction in meta-analysis | ★★★★☆ |
| Chromium + L-Carnitine | Insulin signaling (chromium; not settled); fatty acid transport into mitochondria (L-carnitine) | Small average HbA1c reductions in meta-analyses | Limited data | Not established | ★★☆☆☆ |
Common Misconceptions
"Metabolic supplements are only useful if you have diabetes."
Most of the supplement trials cited in this article enrolled people who already had type 2 diabetes, metabolic syndrome or high triglycerides. We did not review whether any of these supplements prevents prediabetes from progressing to type 2 diabetes. If your blood sugar or other measures are outside the optimal range, ask a clinician about testing, lifestyle changes and whether a supplement is appropriate for you.
"Berberine is a natural alternative to metformin — it works the same way."
Berberine and metformin are not interchangeable. Metformin is a prescribed medicine with decades of safety and outcome data, while berberine is a supplement tested mostly in small, short trials of limited quality. A 2012 meta-analysis found no significant difference in glucose control between berberine and oral diabetes drugs including metformin, but the trials were generally of low quality, so this does not show equivalence.5 Do not replace metformin or any prescribed diabetes medicine with berberine.
"If you eat a 'healthy diet' you get all the magnesium you need."
Many people in the US eat less magnesium than the required amount: 48% did in 2005–2006, according to one review.21 Eating less than the required amount does not by itself mean a person is deficient, and not everyone needs a supplement. Magnesium losses through the kidneys are increased in diabetes,22 and magnesium supplements can cause diarrhea and can build up in people with kidney disease.22,25 Ask a clinician whether a supplement is right for you.
"Omega-3 supplements are just a heart health product — not relevant to blood sugar."
In a 2022 meta-analysis of 46 trials in type 2 diabetes, omega-3 supplements slightly lowered triglycerides, C-reactive protein and HbA1c (by 0.19 percentage points) but did not significantly change fasting blood sugar or insulin resistance.43 Their best-supported effect is on triglycerides at high doses, and they carry safety questions, including atrial fibrillation and interactions with blood thinners (see the omega-3 section).
"CoQ10 is just for people taking statins — healthy people don't need it."
CoQ10 has been tested in people with metabolic disorders, and meta-analyses found small average improvements in glucose and blood pressure.31,33 We did not find evidence that healthy adults need a CoQ10 supplement. Whether CoQ10 helps statin muscle symptoms is unsettled, and CoQ10 can interact with warfarin (see the CoQ10 section).
How These Supplements Were Used in Studies
These supplements are thought to work in different ways, but we did not find any trial that tested all of them together, and berberine, chromium, L-carnitine, magnesium and CoQ10 can each lower blood glucose, so their effects may add up. The box below only illustrates the doses and timing used in the studies cited above. It is not a tested regimen or a recommendation. Talk to a prescriber or pharmacist before taking several at once, especially if you take any medicine.
- Berberine: trial doses ranged from 0.6 to 1.5 g a day; ask your prescriber or pharmacist first, especially if you take any prescription medicine
- Magnesium: the trials above used about 370–380 mg of elemental magnesium a day; the US upper limit for supplemental magnesium is 350 mg a day, so add up all sources, and ask a doctor first if you have kidney disease
- CoQ10: the largest blood pressure effect in one analysis was at about 100–200 mg a day; ask your prescriber first if you take warfarin
- Omega-3: 2–4 g a day of EPA+DHA is used under medical supervision for high triglycerides; atrial fibrillation was more common with doses above 1 g a day in large trials, so check with a clinician before taking high doses
- Chromium and L-carnitine: trials used 200–1,000 µg a day of chromium and up to 4 g a day of L-carnitine; ask first if you take diabetes or thyroid medicine
- Monitoring: if you have diabetes or take glucose-lowering medicine, ask your prescriber how to watch for low blood sugar (shakiness, sweating, confusion) and what to do. Do not change a medicine because of home readings or because of this article
Kasivit Products for Metabolic Health
Kasivit sells the products below. They are listed for reference. The studies cited above did not test Kasivit products, and this article does not claim that any product has the effects reported in them. Check the product label for ingredients and amounts, and ask a prescriber or pharmacist before use if you take any medicine.
Kasivit Berberine for Healthy Metabolism
500 mg berberine HCl per capsule, 60 vegan capsules. Standardized extract. Gluten-free, vegan, no fillers. Berberine can interact with many medicines and is not a replacement for a prescribed medicine; avoid it during pregnancy and breastfeeding, and ask a pharmacist or prescriber before use.
Shop Berberine →
Kasivit Foundation Bundle
Three supplements in a single bundle. A 2026 expert consensus on nutrition support for people taking GLP-1 medicines notes a significant lack of direct evidence,60 and we did not find clinical studies of berberine together with GLP-1 medicines; a 2026 review lists additive blood-glucose lowering as a possible interaction.10 If you take a GLP-1 or any other prescription medicine, talk to your prescriber or pharmacist before adding supplements.
View Bundle — $92.99 →Frequently Asked Questions
- Berberine has the most trials of the five for glucose and blood fats, but most are small and of limited quality. Meta-analyses found lower HbA1c and triglycerides on average; berberine alone did not lower LDL cholesterol significantly. It interacts with many medicines and is not a replacement for diabetes medicine.
- Magnesium supplements lowered blood pressure and fasting glucose slightly in meta-analyses. About half of US adults eat less than the required amount, which is not the same as deficiency. The glycinate form has not been compared with other forms in trials, and people with kidney disease should ask a doctor first.
- CoQ10 produced small average improvements in blood pressure and glucose in meta-analyses. It has not been established that statin users need it, the evidence that it helps statin muscle symptoms is mixed, and it can interact with warfarin.
- Omega-3s (EPA/DHA) lower triglycerides at high, prescription-level doses. Large trials linked omega-3 supplements to more atrial fibrillation, especially above 1 g a day, so check with a clinician first if you have heart disease or take a blood thinner.
- Chromium and L-carnitine have each been tested for glucose control, with small average effects. L-carnitine raised TMAO in one review and can counteract thyroid hormone, and chromium picolinate has rarely caused hypersensitivity reactions.
- These supplements have not been tested together. Several can lower blood glucose and several interact with medicines, so talk to a prescriber or pharmacist before combining them, and never change a prescribed medicine because of a supplement.
Disclaimer: This article is for educational purposes only and does not constitute medical advice. The supplements discussed are not intended to diagnose, treat, cure, or prevent any disease. Do not stop, reduce, switch or change any prescribed medicine based on information in this article; ask your prescriber or pharmacist. Several of these supplements can interact with medicines, lower blood sugar or blood pressure, or be unsuitable for people with kidney disease, thyroid conditions, heart-rhythm problems or bleeding risks, or who take blood thinners. Ask a doctor or pharmacist before use if you are pregnant or breastfeeding, and do not give supplements to children without medical advice. Individuals with diabetes, cardiovascular disease, or other metabolic conditions should consult a qualified healthcare provider before starting any supplement, particularly if they are taking prescription medications.
