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Peer-Reviewed Research Only

What's Really In Your Supplements?

Clinical evidence for every ingredient. No hype. No guesswork. Backed by peer-reviewed trials.

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Condition Guides
279+
Ingredients Analyzed
1,700+
Products Tracked
2,600+
Clinical Studies Cited

Editor-Featured

Quality-verified supplements our team endorses

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Toniiq 1000mg Ultra High Strength St. John's Wort Capsule

1000mg Ultra High Strength St. John's Wort

Toniiq
(3,483)
Staff Pick
Limited time deal20% offClinical doseTested
1000mg per capsule (4:1 concentrated extract, 0.3% hypericin)

Highest potency per capsule in this roundup at 1000mg concentrated extract. Third-party tested. 120 capsules provide a 4-month supply at 1 capsule/day. The 4:1 concentration ratio means 1000mg is equivalent to 4000mg of raw herb.

Sunergetic Premium Berberine Supplement Capsule

Premium Berberine Supplement

Sunergetic
(7,202)
Therapeutic doseThird-Party Tested, Non-GMO
1,200mg berberine HCl per serving (2 capsules)

Exceptional value at $0.30/serving with a full 1,200mg clinical dose from 2 capsules. Third-party tested and Non-GMO verified. One of the best-selling berberine products on Amazon with 15,000+ reviews and a 4.5-star average.

Sunergetic Magnesium Oxide Citrate 500mg Capsule (Vegetable)

Magnesium Oxide Citrate 500mg

Sunergetic
(4,222)
Clinical doseGMP manufactured; third-party testing not publicly disclosed
500mg magnesium per 2-capsule serving; 60 servings per bottle

One of the highest-rated magnesium supplements on Amazon with 4,222 reviews at 4.6 stars. The oxide + citrate combination provides both broad mineral supply (oxide) and better-absorbed citrate component. At $16.95 for 60 servings, value per dose is exceptional.

Sunergetic Electrolyte Capsules Keto Capsule

Electrolyte Capsules Keto

Sunergetic
(2,351)
Proprietary blendGMP Certified
Full-spectrum electrolyte blend per serving

The capsule form delivers four electrolytes in WHO-aligned ratios without the sugar load that makes sports drinks problematic. Ketogenic and low-carb dieters excrete sodium and potassium at accelerated rates and respond particularly well to supplemental repletion — this is the most evidence-driven choice for that cohort. Over 2,350 reviews averaging 4.5 stars.

VERIFIED

Third-Party Tested

Products verified by independent labs for purity and potency.

REVIEWED

Evidence Based

Every article reviewed by our editorial team against published research.

CURRENT

Updated July 2026

Research and recommendations refreshed with the latest clinical data.

03

Featured Ingredients

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Magnesium
S
Mineral Supplement

Magnesium

Magnesium may help some people sleep better, especially when intake is low or poor sleep is tied to stress, muscle tension, or restlessness. It is not a sedative, and sleep trial results are mixed, but magnesium glycinate is commonly preferred before bed because it is generally well tolerated and less laxative than citrate or oxide.

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Strong

Vitamin D3

Fat-Soluble Vitamin

Vitamin D3 is essential for bone health, immune function, and mood regulation. An estimated 42% of U.S. adults are deficient. Most adults benefit from 1,000-4,000 IU daily, and a 2017 meta-analysis found supplementation reduced the risk of acute respiratory infections by 12%.

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Strong

Omega-3

Essential Fatty Acid

Omega-3 fatty acids (EPA + DHA) reduce inflammation, support heart and brain health, and may improve mood. The REDUCE-IT trial showed high-dose EPA (4g/day) reduced cardiovascular events by 25%. Most adults benefit from 1,000-2,000mg combined EPA+DHA daily.

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Strong

Probiotics

Live Microorganisms

Probiotics are live beneficial bacteria that support gut health, immunity, and mood through the gut-brain axis. A 2018 meta-analysis found significant IBS symptom reduction with multi-strain probiotics. Benefits are strain-specific — choose based on your health goal. Typical dose: 10-50 billion CFU daily. Look for third-party tested products with verified potency through the expiration date.

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Strong

Ashwagandha

Adaptogenic Herb

Yes, ashwagandha is one of the most clinically studied adaptogens, with over 22 published clinical trials backing its benefits. A 2019 meta-analysis found it reduced stress scores by 44% and cortisol by 23% compared to placebo. The recommended dose is 300-600mg of root extract (KSM-66, standardized to withanolides) daily.

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Strong

Melatonin

Neurohormone

Melatonin is the most well-studied natural sleep supplement, shown in a meta-analysis of 19 RCTs to reduce sleep onset latency by 7-12 minutes and improve sleep quality. Importantly, more is NOT better — doses as low as 0.5mg can be as effective as 5mg for sleep onset. It is also the best-evidenced supplement for jet lag.

06 / Our Standards

Our Research Standards

Every article is written and reviewed by our editorial team against peer-reviewed clinical research, and cites its sources. We never recommend products based on business partnerships.

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