Doctor's Best · Citrulline · Powder
Is Doctor's Best L-Citrulline Powder underdosed?
Verdict
3 g per servingone dose · studies use 4–5.33 g of l-citrulline
Below research doseOne serving contains 3 g; studies use 4–5.33 g in one dose before training. The label's directions allow 1 serving a day.
One serving gives 3 g, so reaching the low end of what studies use (4 g) takes 1.3 servings at once; it ranks 3rd of 16 citrulline supplements here by dose.
To reach the research dose. It would take 2 servings at once (2 scoops), 6 g, to reach the 4 g studies use, more than the label's directions, which allow 1 serving a day.
What the label says
- L-Citrulline per serving
- 3 g in 1 scoop (3 g)
- Servings a day
- 1 serving a day
- L-Citrulline a day, as directed
- 3 g
- Research dose
- 4–5.33 g Evidence: Weak
Suggested adult use: Take 1 scoop daily with 8 oz. of water or beverage of your choice, before workouts, or as recommended by a nutritionally informed physician.
More about l-citrulline: forms, timing and the studies behind the dose.
Same category, compared
All 16 citrulline supplements we checked, ranked by dose (commission never changes the order). Studies use 4–5.33 g of l-citrulline; servings counted to 4 g.
| Product | Per serving | Servings to reach it | Form |
|---|---|---|---|
| BulkSupplements L-Citrulline 3000 mg Capsules | 3 g | 1.3 at once | Capsules |
| BulkSupplements L-Citrulline Powder | 3 g | 1.3 at once | Powders |
| Doctor's Best L-Citrulline Powder (this product) | 3 g | 1.3 at once | Powders |
| Nutricost L-Citrulline Powder | 3 g | 1.3 at once | Powders |
| Best Naturals L-Citrulline 2000 mg Tablets | 2 g | 2 at once | Tablets |
| Kaged Citrulline | 2 g | 2 at once | Powders |
| Micro Ingredients L-Citrulline Malate 2:1 | 2 g | 2 at once | Powders |
| NutraBio L-Citrulline (Fermented) | 2 g | 2 at once | Powders |
| Nutricost L-Citrulline Malate 2:1 Powder | 2 g | 2 at once | Powders |
| NOW L-Citrulline 750 mg Capsules | 1.5 g | 2.7 at once | Capsules |
| NOW L-Citrulline Pure Powder | 1.5 g | 2.7 at once | Powders |
| Nutricost L-Citrulline 1,500 mg Capsules | 1.5 g | 2.7 at once | Capsules |
| Double Wood L-Citrulline 1200 mg Capsules | 1.2 g | 3.3 at once | Capsules |
| NOW Sports L-Citrulline 1,200 mg Tablets | 1.2 g | 3.3 at once | Tablets |
| Swanson L-Citrulline 850 mg Capsules | 850 mg | 4.7 at once | Capsules |
| Amazing Formulas L-Citrulline 750 mg Capsules | 750 mg | 5.3 at once | Capsules |
Where the reference doses come from
- L-Citrulline, 4–5.33 g: Gough et al., 2021; Vårvik et al., 2021.
- Label data: National Institutes of Health, Office of Dietary Supplements. Dietary Supplement Label Database, 2026. https://dsld.od.nih.gov/. Label 302684, including its servings a day.
For a supplement taken as one dose we judge one serving, and show the most the label allows in a day. Read the full methodology or the corrections log.