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Best Supplement Guides

If you just want the answer - which one should I actually buy? - start here. Each guide pairs the evidence rating for the ingredient with our execution scores for the products, so the top pick is the one that earns it, not the one that paid for the slot. Every pick is independently scored and kept current.

Best Vitamin D3 Supplement

Top pick: Kirkland Signature Kirkland Signature Vitamin D3 50 mcg (2000 IU) - $0.02/day

10 products scored

Strong Evidence
95/100

Best Magnesium for Sleep

Top pick: Doctor's Best Doctor's Best High Absorption Magnesium Glycinate Lysinate - $0.17/day

15 products scored

Likely Effective
90/100

Best Magnesium Glycinate

Top pick: Doctor's Best Doctor's Best High Absorption Magnesium Glycinate Lysinate - $0.17/day

15 products scored

Likely Effective
90/100

Best Fish Oil Supplement

Top pick: Sports Research Sports Research Triple Strength Omega-3 - $0.22/day

12 products scored

Strong Evidence
86/100

Best Creatine Supplement

Top pick: Naked Nutrition Naked Creatine - $0.18/day

10 products scored

Strong Evidence
93/100

Best Ashwagandha Supplement

Top pick: Nootropics Depot KSM-66 Ashwagandha Extract 300mg - $0.38/day

10 products scored

Likely Effective
91/100

Best Multivitamin

Top pick: Kirkland Signature Daily Multi Vitamins & Minerals - $0.03/day

14 products scored

Likely Effective
91/100

Best Probiotic Supplement

Top pick: NOW Foods Probiotic-10 25 Billion - $0.30/day

10 products scored

Likely Effective
86/100

Best Collagen Supplements

Top pick: Naked Nutrition Naked Collagen - $0.70/day

13 products scored

Mixed Evidence
90/100

Best Turmeric Curcumin Supplement

Top pick: Thorne Meriva SF (Soy-Free) Curcumin Phytosome - $0.67/day

11 products scored

Mixed Evidence
90/100

Best Vitamin B12 Supplement

Top pick: Nature Made Nature Made Vitamin B12 1000 mcg - $0.07/day

8 products scored

Strong Evidence
91/100

Best Zinc Supplement

Top pick: Jarrow Formulas Zinc Balance 15 mg - $0.10/day

8 products scored

Strong Evidence
90/100

Best Melatonin Supplement

Top pick: Life Extension Melatonin 300 mcg (0.3mg) - $0.08/day

8 products scored

Strong Evidence
91/100

Best Whey Protein Isolate

Top pick: Optimum Nutrition Gold Standard 100% Whey - $1.09/day

9 products scored

Strong Evidence
91/100

Best CoQ10 Supplement

Top pick: Nature Made Nature Made CoQ10 200mg - $0.28/day

8 products scored

Likely Effective
88/100

Best Iron Supplement

Top pick: Nature Made Nature Made Iron 65mg (Ferrous Sulfate) - $0.02/day

8 products scored

Strong Evidence
94/100

Best Cod Liver Oil Supplement

Top pick: Nordic Naturals Nordic Naturals Arctic Cod Liver Oil (Lemon) - $0.60/day

10 products scored

Likely Effective
91/100

Best Multivitamin for Men

Top pick: Kirkland Signature Daily Multi Vitamins & Minerals - $0.03/day

14 products scored

Likely Effective
91/100

Best Multivitamin for Women

Top pick: Kirkland Signature Daily Multi Vitamins & Minerals - $0.03/day

14 products scored

Likely Effective
91/100

Best Multivitamin for Seniors

Top pick: Kirkland Signature Daily Multi Vitamins & Minerals - $0.03/day

14 products scored

Likely Effective
91/100

Best Protein Powder for Women

Top pick: Optimum Nutrition Gold Standard 100% Whey - $1.09/day

9 products scored

Strong Evidence
91/100

Best Supplements for Athletes

Top pick: Naked Nutrition Naked Creatine - $0.18/day

10 products scored

Strong Evidence
93/100

Best Supplements for Vegans

Top pick: Nature Made Nature Made Vitamin B12 1000 mcg - $0.07/day

8 products scored

Strong Evidence
91/100

Best Supplements for Runners

Top pick: Nature Made Nature Made Iron 65mg (Ferrous Sulfate) - $0.02/day

8 products scored

Strong Evidence
94/100

Best Supplements for Bodybuilding

Top pick: Optimum Nutrition Gold Standard 100% Whey - $1.09/day

9 products scored

Strong Evidence
91/100

Best Supplements for Women Over 50

Top pick: Kirkland Signature Daily Multi Vitamins & Minerals - $0.03/day

14 products scored

Likely Effective
91/100

Best Supplements for Men Over 50

Top pick: Nature Made Nature Made CoQ10 200mg - $0.28/day

8 products scored

Likely Effective
88/100

Best Supplements for Teens

Top pick: Kirkland Signature Daily Multi Vitamins & Minerals - $0.03/day

14 products scored

Likely Effective
91/100

Best Supplements for Pregnancy

Top pick: Nature Made Nature Made Iron 65mg (Ferrous Sulfate) - $0.02/day

8 products scored

Strong Evidence
94/100

Best Supplements for Breastfeeding

Top pick: Sports Research Sports Research Triple Strength Omega-3 - $0.22/day

12 products scored

Strong Evidence
86/100

Best Supplements for the Elderly

Top pick: Kirkland Signature Kirkland Signature Vitamin D3 50 mcg (2000 IU) - $0.02/day

10 products scored

Strong Evidence
95/100

Best Supplements for Stress & Calm

Top pick: Nootropics Depot KSM-66 Ashwagandha Extract 300mg - $0.38/day

10 products scored

Likely Effective
91/100

Best Supplements for Sleep

Top pick: Life Extension Melatonin 300 mcg (0.3mg) - $0.08/day

8 products scored

Strong Evidence
91/100

Best Supplements for Gut Health

Top pick: NOW Foods Probiotic-10 25 Billion - $0.30/day

10 products scored

Likely Effective
86/100

Best Supplements for Joint Comfort & Mobility

Top pick: Thorne Meriva SF (Soy-Free) Curcumin Phytosome - $0.67/day

11 products scored

Mixed Evidence
90/100

Best Supplements for Brain Health

Top pick: Sports Research Sports Research Triple Strength Omega-3 - $0.22/day

12 products scored

Strong Evidence
86/100

Best Supplements for Heart Health

Top pick: Nature Made Nature Made CoQ10 200mg - $0.28/day

8 products scored

Likely Effective
88/100

Best Supplements for Muscle Recovery

Top pick: Naked Nutrition Naked Creatine - $0.18/day

10 products scored

Strong Evidence
93/100

Best Supplements for Immune Support

Top pick: Jarrow Formulas Zinc Balance 15 mg - $0.10/day

8 products scored

Strong Evidence
90/100

Best Supplements for Hair Growth

Top pick: Naked Nutrition Naked Collagen - $0.70/day

13 products scored

Mixed Evidence
90/100

Best Supplements for Skin Health

Top pick: Naked Nutrition Naked Collagen - $0.70/day

13 products scored

Mixed Evidence
90/100

Best Supplements for Inflammation

Top pick: Thorne Meriva SF (Soy-Free) Curcumin Phytosome - $0.67/day

11 products scored

Mixed Evidence
90/100

Best Supplements for Energy

Top pick: Nature Made Nature Made Vitamin B12 1000 mcg - $0.07/day

8 products scored

Strong Evidence
91/100

Best Supplements for Bone Health

Top pick: Kirkland Signature Kirkland Signature Vitamin D3 50 mcg (2000 IU) - $0.02/day

10 products scored

Strong Evidence
95/100

Best Supplements for Testosterone

Top pick: Nootropics Depot KSM-66 Ashwagandha Extract 300mg - $0.38/day

10 products scored

Likely Effective
91/100

Best Supplements for Weight Loss

Top pick: NOW Foods Probiotic-10 25 Billion - $0.30/day

10 products scored

Likely Effective
86/100

Best Magnesium for Stress & Calm

Top pick: Doctor's Best Doctor's Best High Absorption Magnesium Glycinate Lysinate - $0.17/day

15 products scored

Likely Effective
90/100

Best Magnesium for Muscle Cramps

Top pick: Doctor's Best Doctor's Best High Absorption Magnesium Glycinate Lysinate - $0.17/day

15 products scored

Likely Effective
90/100

Best Magnesium L-Threonate for Cognitive Support

Top pick: Sports Research Sports Research Magtein Magnesium L-Threonate - $1.00/day

10 products scored

Weak Evidence
94/100

Best Fish Oil for Heart Health

Top pick: Sports Research Sports Research Triple Strength Omega-3 - $0.22/day

12 products scored

Strong Evidence
86/100

Best Probiotics for Digestive Comfort

Top pick: NOW Foods Probiotic-10 25 Billion - $0.30/day

10 products scored

Likely Effective
86/100

Best Probiotic for Women

Top pick: NOW Foods Probiotic-10 25 Billion - $0.30/day

10 products scored

Likely Effective
86/100

Best Low-Dose Melatonin

Top pick: Life Extension Melatonin 300 mcg (0.3mg) - $0.08/day

8 products scored

Strong Evidence
91/100

Best Turmeric for Joint Comfort

Top pick: Thorne Meriva SF (Soy-Free) Curcumin Phytosome - $0.67/day

11 products scored

Mixed Evidence
90/100

Best Ashwagandha for Stress

Top pick: Nootropics Depot KSM-66 Ashwagandha Extract 300mg - $0.38/day

10 products scored

Likely Effective
91/100

Best Collagen for Joints

Top pick: Naked Nutrition Naked Collagen - $0.70/day

13 products scored

Mixed Evidence
90/100

Best DIM Supplements for Estrogen Metabolism Support

Top pick: Thorne Hormone Advantage (DIM + Pomegranate + Sulforaphane), 60 caps - $0.85/day

8 products scored

Mixed Evidence
82/100

Best Vitex (Chasteberry) Supplements for Menstrual Cycle Comfort

Top pick: Nature's Way Femaprin Vitex Extract with Vitamin B6, 60 Capsules - $0.30/day

7 products scored

Likely Effective
86/100

Best Myo-Inositol for Cycle Regularity and Ovulatory Support

Top pick: Theralogix Ovasitol Inositol Powder, 90-Day Supply (Myo + D-Chiro 40:1) - $0.83/day

7 products scored

Likely Effective
95/100

Best Enteric-Coated Peppermint Oil for Digestive Comfort

Top pick: IM HealthScience IBgard Peppermint Oil Capsules, 96 Count (2-pack) - $0.57/day

8 products scored

Likely Effective
89/100

Best Saffron Supplement for Mood Support

Top pick: Sports Research Pure Saffron 30mg with affron, 60 Veggie Softgels - $0.50/day

8 products scored

Mixed Evidence
91/100

Best SAMe Supplement for Mood and Joint Comfort

Top pick: Nature Made SAM-e Complete 400 mg, 60 Enteric Coated Tablets - $1.00/day

8 products scored

Likely Effective
92/100

Best Cranberry Supplement for Urinary Tract Health

Top pick: Theralogix TheraCran One Cranberry, 36mg PAC, 90 Capsules (90-Day Supply) - $0.59/day

9 products scored

Mixed Evidence
94/100

Best Valerian Root Supplement for Sleep Support

Top pick: Bluebonnet Nutrition Standardized Valerian Root Extract 250mg - $0.40/day

9 products scored

Mixed Evidence
90/100

Best Ginger Supplement for Digestive Comfort

Top pick: NOW Foods Ginger Root Extract 250mg (5% gingerols), 90 ct - $0.13/day

8 products scored

Likely Effective
89/100

Best Greens Powder

Top pick: NAKED Nutrition Naked Greens (35 Servings) - $0.91/day

13 products scored

Mixed Evidence
77/100

Best Protein Powder

Top pick: NOW Sports Sports Whey Protein Concentrate, Unflavored - $1.23/day

10 products scored

Strong Evidence
90/100

Best Electrolyte Powder

Top pick: Skratch Labs Sport Hydration Drink Mix - Variety Pack - $1.80/day

13 products scored

Likely Effective
77/100

Best Pre-Workout

Top pick: Transparent Labs BULK Pre-Workout - $1.67/day

10 products scored

Mixed Evidence
82/100

Best Meal Replacement Shake

Top pick: Huel Huel Black Edition (Chocolate, 17 Servings) - $3.18/day

11 products scored

Mixed Evidence
78/100

Best Budget Greens Powder

Top pick: NAKED Nutrition Naked Greens (35 Servings) - $0.91/day

13 products scored

Mixed Evidence
77/100

Best Greens Powder Without Proprietary Blends

Top pick: NAKED Nutrition Naked Greens (35 Servings) - $0.91/day

13 products scored

Mixed Evidence
77/100

FDA Disclaimer: These statements have not been evaluated by the Food and Drug Administration. The products discussed on this page are not intended to diagnose, treat, cure, or prevent any disease. Always consult with a qualified healthcare professional before starting any supplement regimen.