Hemp Protein
Summary
Hemp protein has two human trials. In 35 adults with mild hypertension, 50 g/day for 6 weeks lowered 24-hour blood pressure slightly versus casein (grade D). In 34 trained adults, 60 g/day during 8 weeks of lifting gave results similar to soy, with small sex-specific differences (grade D). Its protein quality score (PDCAAS about 46–66%) is modest; lysine is the limiting amino acid.
Key facts
- Ground meal or protein concentrate from hemp seeds (Cannabis sativa) after the oil is pressed out[2][1]
- 24-hour blood pressure versus casein (D); muscle and strength gains during resistance training versus soy (D)[3][4]
- PDCAAS 46–51% for hemp seed meal and 63–66% for dehulled seed; lysine is the first limiting amino acid[2]
- FDA had no questions about GRAS status for hemp seed protein powder (GRN 771); hemp seed ingredients contain only trace THC[1]
- None for hemp protein itself; it counts toward total protein intake[1]
- 2 graded human outcomes on this page
- October 10, 2026
How it works
ProposedHemp protein supplies amino acids for muscle protein synthesis, though its low lysine and lower digestibility make it a less complete source. In the blood pressure trial, hemp protein lowered plasma ACE and renin activity and raised nitric oxide compared with casein.[2][3]
What the human research says
Human trials only, one row per outcome. The form column shows what each trial actually tested. Grades follow our evidence-grading policy.
At a glance: strongest evidence per outcome
| Outcome | Grade | Effect | Strongest evidence | Rows |
|---|---|---|---|---|
| Blood pressure | Grade D | Improved | Crossover RCT · n = 35 · 2024 | 1 row |
| Muscle | Grade D | Mixed | RCT · n = 34 · 2024 | 1 row |
Every graded row
| Outcome | Effect | Grade | Best evidence | PMID |
|---|---|---|---|---|
| 24-hour blood pressure versus casein | Improved | Grade D | Crossover RCT · n = 35 · 2024 Adults with mild hypertension (systolic 130–160 mmHg) Form: Hemp seed protein powder, alone or with 5 g hemp-derived bioactive peptides · Dose: 50 g/day · Duration: 6 weeks per treatment, 2-week washouts Compared with casein, 24-hour blood pressure was 133.5/78.9 mmHg after hemp protein and 128.1/76.0 mmHg after hemp protein plus peptides, from 135.1/80.0 mmHg (P<0.0001). Plasma ACE and renin activity fell and nitric oxide rose versus casein. | 38710445 (opens PubMed)Source [3] |
| Muscle size, strength and fatigue during resistance training versus soy | Mixed | Grade D | RCT · n = 34 · 2024 Resistance-trained young men and women (mean age about 30) Form: Hemp protein product (40 g protein and 9 g oil per 60 g) · Dose: 60 g/day · Duration: 8 weeks of training about 4 times a week Hemp increased elbow flexor thickness in women, while soy did so in men; men on hemp kept more twitch torque after a fatigue test than men on soy. The abstract reports only these sex-specific differences. | 37847288 (opens PubMed)Source [4] |
Forms
| Form | Elemental % | Absorption (human data) | GI tolerance | Studied for |
|---|---|---|---|---|
| Hemp protein powder or concentrate (pressed seed meal) | Varies[1][2][3][4] | Protein digestibility 90.8–97.5% for hemp seed meal in a rat assay; PDCAAS 46–51%.[2] | The trial abstracts do not report adverse events; FDA had no questions about GRAS status for hemp seed protein powder.[1][3] | Both human trials (50–60 g/day) |
| Hulled hemp seed (hemp hearts) | Varies[1][2] | Removing the hull raised digestibility and PDCAAS to 63–66%.[2] | Food ingredient; FDA accepted GRAS status for hulled hemp seed (GRN 765).[1] | Food use; not tested in outcome trials |
Studied doses
Doses studied in human trials ranged from 50 to 60 g/day of hemp protein powder, for 6 to 8 weeks. The training trial's 60 g provided 40 g of protein and 9 g of oil.[3][4]
Interactions
Published interactions only: each row cites a source. No row means none was found in our sources, not that a combination is safe.
None found in our sources.
Who should be careful
- Needing a complete protein source
- Hemp protein is low in lysine and has a PDCAAS of only 46–66%; single plant proteins generally aid recovery less than whey.[2][5]
- Strict THC limits
- Hemp seed foods can carry trace THC from contact with other plant parts; some hemp seed oils tested above EU limits.[1][7]
- Low blood pressure
- Hemp protein lowered 24-hour blood pressure slightly versus casein in people with mild hypertension.[3]
Talk to your pharmacist or clinician before starting a supplement, especially if you take prescription medicines.
Safety
Hemp protein is a food ingredient with a clean short-term record; the main issue is trace cannabinoids.
- GRAS status
- FDA had no questions about the conclusion that hemp seed protein powder, hulled seed and seed oil are GRAS for their intended food uses.[1]
Food sources
| Food | Serving | Amount |
|---|---|---|
| Dehulled hemp seeds (hemp hearts) | 30 g | 10770 mg[2] |
How to read the label
- Label dose vs clinical doseTrials used 50–60 g of powder a day, about two typical scoops or more. Check grams of protein per serving, since hemp powders vary from about 40% protein upward.[3][4][2]
- Hemp protein is not CBDHemp seed protein contains only trace THC and CBD and cannot make you high; CBD or THC added to food is prohibited in the US.[1]
- Seed meal vs hulled seedDehulled seed has higher protein quality than whole seed or hull-containing meal.[2]
Cost per studied dose, without the sales pitch
Compare any product you already have by the amount it delivers, not by capsule count or front-of-pack weight.
Cost per studied dose
Enter the price, servings and the amount per serving from your label.
Frequently asked questions
Is hemp protein a complete protein?
Not fully: lysine is its limiting amino acid, giving a PDCAAS of about 46–66%, comparable to some grains and pulses.[2]
Does hemp protein build muscle?
In an 8-week trial in trained adults, 60 g/day performed about like soy, with small differences by sex.[4]
Can hemp protein lower blood pressure?
In one 6-week trial in mild hypertension, 50 g/day lowered 24-hour blood pressure slightly compared with casein.[3]
Will hemp protein make me high?
No. FDA says hemp seed ingredients contain only trace THC picked up during processing and cannot make consumers high.[1]
Sources
- [1]FDA Responds to Three GRAS Notices for Hemp Seed-Derived Ingredients for Use in Human Food (constituent update, December 20, 2018). U.S. Food and Drug Administration, 2018. fact-sheet
- [2]Evaluating the quality of protein from hemp seed (Cannabis sativa L.) products through the use of the protein digestibility-corrected amino acid score method.. J Agric Food Chem, 2010. animal-study
- [3]Hemp seed protein and its hydrolysate compared with casein protein consumption in adults with hypertension: a double-blind crossover study.. Am J Clin Nutr, 2024. crossover-RCT
- [4]Effects of hemp supplementation during resistance training in trained young adults.. Eur J Appl Physiol, 2024. RCT
- [5]Effect of Plant-Based Proteins on Recovery from Resistance Exercise-Induced Muscle Damage in Healthy Young Adults-A Systematic Review.. Nutrients, 2025. systematic-review
- [6]Cannabis-derived food products: a global review of THC exposure, safety and forensic frameworks.. Food Chem Toxicol, 2026. review
- [7]Quantification of sixteen cannabinoids in hemp seed edible oils and the influence of thermal processing on cannabinoid contents and profiles.. Food Addit Contam Part A Chem Anal Control Expo Risk Assess, 2024. observational
What changed
- First draft. Every PMID checked against NCBI E-utilities esummary (title and year taken from the record) and abstracts read for the cited rows.
- Adversarial review pass: every evidence row re-read against its PubMed abstract. Official source opened before citing: FDA constituent update on GRAS notices GRN 765, 771 and 778 (December 20, 2018). No NIH ODS, NCCIH or LPI page covers hemp protein. Industry ties: Manitoba Harvest supplied the protein for the blood pressure trial (PMC11251217); funding for the training trial is not stated in PubMed. Retraction, expression-of-concern, erratum and withdrawn checks on all 6 PMIDs: none flagged. Page set indexable. Independent browser review (4 parallel reviewers, every evidence row checked against its abstract on the Vercel preview) found: protein-powder tolerance wording (abstracts silent on adverse events) and mechanism citation scope; fixed.