What is hemp protein? Benefits, side effects, and the research

Hemp protein is a plant protein powder made from hemp seeds. The oil is pressed out and what's left is milled into powder. It has all nine essential amino acids, plus fiber and minerals that refined isolates lose, but it is lower in lysine and leucine than whey or soy. The human research is promising in a few areas, mainly blood pressure, but it's small, and nothing shows hemp protein treats any condition. Side effects are usually digestive and mild. This page covers what it is, what the research does and doesn't show, and who should be careful.

How hemp protein is made

Hemp seeds are about one-third oil and one-quarter protein. To make protein powder, the seeds are pressed to remove most of the oil. The pressed "cake" is then milled and sifted. Sifting out more of the fibrous shell raises the protein percentage.

Cantein is cold-pressed mechanically, with no hexane or other chemical solvents, and certified USDA Organic. A 35g scoop of unflavored Cantein has 28g of protein, so the powder is about 80% protein by weight. Because it isn't refined into an isolate, more of the seed stays in: fiber, magnesium, zinc, and iron. More on how it's grown, pressed, and tested: how Cantein is made and tested.

Hemp protein comes from the seed of industrial hemp, not from the flower. It isn't CBD, and it won't get you high (more on THC below).

Nutrition per scoop

Per 35g scoop Cantein Unflavored Cantein Vanilla or Chocolate
Protein 28g 22g
Calories 110 120
Fat 0g 4g (from MCT)
Fiber 2g 2g
Added sugar 0g 0g
Magnesium 417mg (100% DV) 303mg (70% DV)
Zinc 13mg (120% DV) 10mg (90% DV)
Iron 8mg (45% DV) 6mg (35% DV)
Manganese 7mg (300% DV) 5mg (220% DV)
Leucine 1.80g 1.44g

Full ingredient lists: ingredients and nutrition, per scoop. Hemp protein differs from eating hemp seeds or hemp hearts, which are mostly fat: hemp seeds vs hemp protein powder.

How much fiber is in hemp protein?

It depends on how much of the seed's shell is left in. Most of hemp's fiber is in the shell, so sifting more of it out raises the protein and lowers the fiber. That's why hemp powders range from high-fiber, lower-protein blends to concentrated ones like Cantein.

  • Cantein Unflavored: 2g of fiber and 28g of protein per 35g scoop. The fiber is from the seed itself.
  • Nutiva Peak Protein: 6g of fiber and 15g of protein per serving. Nutiva's Fiber Plus has 11g of each (brand pages, checked October 2, 2026).
  • Cantein Protein + Fiber: 6g of fiber per 35g scoop, from added organic acacia, with 26g of protein in Unflavored or 20g in Vanilla and Chocolate.

If fiber is your main goal, a high-fiber hemp powder or Protein + Fiber gets you there. If protein per scoop matters more, a concentrated powder does. Five brands side by side: hemp protein powders compared.

Is hemp protein a complete protein?

Yes, in the technical sense: it contains all nine essential amino acids. But "complete" doesn't mean every amino acid is present in the ideal amount. In hemp, lysine is the one in shortest supply, and that's what holds back its protein-quality scores.

  • PDCAAS: 46–66% across commercial hemp products, depending on how they were processed (House et al., 2010).
  • DIAAS, the newer FAO method: whey and soy scored above 75, while hemp scored below 60 (Herreman et al., 2020).
  • Digestibility: high. Tested hemp products were roughly 84–98% digestible, though these figures come from rat assays, not people.
  • Leucine, the amino acid most tied to muscle building, is about 6.5% of hemp protein against about 11% of whey.

In practice, the lysine gap is easy to fill over a day with beans, lentils, tofu, or dairy if you eat it. The full breakdown, and a calculator for your own targets: hemp protein amino acids.

The main storage protein in hemp seed is edestin, which makes up about 65–75% of the seed's protein.

Benefits: what the research shows

None of these studies used Cantein, and doses and products differ. Here's the honest summary:

Outcome Study What it found The limit
Blood pressure Samsamikor et al., 2024: randomized crossover, 31 adults with hypertension, six weeks per diet 24-hour systolic blood pressure was 133.5 mmHg on 50g/day of hemp protein vs 137.0 on casein One trial, at 50g/day of hemp protein (about two unflavored scoops). Not a treatment.
Blood sugar after a meal Mollard et al., 2021: two crossover experiments, 27 and 16 adults 20–40g of hemp protein in a smoothie lowered the early glucose rise vs a carbohydrate control Hemp did no better than soy, and the smoothies differed in carbs, fat, and fiber.
Gut hormones Neacsu et al., 2022: 10 adults, one meal each The hemp meal produced the highest GLP-1 hormone response of the meals tested Ten people, one day per meal. The natural hormone is not the GLP-1 medication, and buckwheat, not hemp, was most filling.
Strength training Kaviani et al., 2024: 34 trained adults, eight weeks, hemp vs soy Mixed, sex-specific results for muscle thickness and fatigue One small trial. Muscle protein synthesis wasn't measured.

Beyond the trials, the benefits that hold up are nutritional: a lot of protein per calorie, no dairy or soy, and real amounts of magnesium, zinc, iron, and fiber. Our evidence review goes through each study in more detail.

What hasn't been shown

  • That hemp protein prevents or treats high blood pressure, diabetes, or any disease.
  • That it builds muscle as well as whey. No head-to-head trial exists. Hemp vs whey covers what's known.
  • That it causes weight loss. Protein in general helps people feel full, but there's no long-term hemp-specific evidence.
  • That it works like or alongside GLP-1 medications. It doesn't, and nothing suggests it does. If you take one, see protein and fiber on a GLP-1.

Side effects and who should be careful

Digestive upset

The most common complaint with any protein powder is bloating or gas, and hemp isn't exempt. Hemp has a little fiber (2g per Cantein scoop), and any new food every day can take adjusting to. Start with half a scoop in water for a few days. If shakes bother you, why protein powder bloats you has a 12-day test to find the cause.

Allergy

Hemp seed allergy is uncommon, but it exists. Anaphylaxis after eating hemp seed has been reported since 2003 (Stadtmauer et al., 2003), and people with cannabis allergy can react to hemp foods and to some fruits, nuts, and vegetables (Decuyper et al., 2017). If you're allergic to cannabis, or a hemp food has ever given you hives, swelling, or trouble breathing, avoid hemp protein and talk to an allergist.

THC and drug tests

Hemp seeds don't naturally contain THC; traces come from contact with the flower during harvest. The FDA has said hemp seed foods aren't capable of making people "high." When Eurofins tested the hemp protein in Cantein, no THC or CBD was detected. Drug tests are a narrower question. Research suggests ordinary hemp food intake is unlikely to cause a positive result, but we can't promise how any test will come out. Details: does Cantein contain THC?

Heavy metals

All plants take up some metals from soil, and hemp is good at it. It has been studied as a way to clean up contaminated land. In one field trial on polluted soil, hemp seeds took up relatively high amounts of cadmium and nickel, though little lead (Linger et al., 2002). That's why where hemp is grown, and testing, matters. In Eurofins testing of the hemp protein in Cantein, a scoop of unflavored had 0.22µg of lead and 0.49µg of cadmium, both under California's strict Prop 65 levels. Full results and what they mean: lead and heavy metals in protein powder.

Manganese, if you take a lot

Hemp protein is naturally very high in manganese. One scoop of unflavored Cantein has 7mg. The National Academies' upper limit for adults is 11mg a day from all sources, food included. One scoop a day keeps most people comfortably under. Two scoops of unflavored a day (14mg) is over the limit before counting the rest of your diet, so if you want more protein, get the rest from other foods.

Medical conditions

If you have kidney disease, have been told to limit protein, or are pregnant, check with your clinician before adding any protein powder. This page is general information, not medical advice.

How to use it

  • Dose: one scoop is a useful protein serving for most people. For how much protein you need across a day, use our protein calculator, or see 100g of protein without whey or protein after 50 without dairy.
  • Mixing: blend rather than shake if you can. Hemp has an earthy taste and a slightly thicker texture than whey. It thickens if left to sit.
  • Taste: unflavored is nutty and works with fruit, oats, or savory food. Vanilla and chocolate are sweetened with organic monk fruit. Ideas: hemp protein recipes.

A short history of hemp protein

Hemp seed is an old food. It has been eaten in China for at least 3,000 years (Callaway, 2004). Ancient Chinese texts count it among the "five grains" and describe it eaten as a snack, cooked into porridge, pressed for cooking oil, and mashed as a seasoning. Until around the 10th century, before higher-yielding grains spread, it was an important part of the Chinese diet (Liu et al., 2017).

Its protein was among the first that modern chemistry studied closely. In 1892 the American chemist Thomas Osborne described crystallized protein from hemp seed, and in 1894 he named it edestin, from the Greek for "edible." Edestin is still the main protein in hemp seed.

Hemp protein powder is much newer. Canada banned hemp farming in 1938 and allowed licensed commercial growing again from March 1998. In the US, the 2018 Farm Bill removed hemp from the federal definition of marijuana, and that same year the FDA reviewed hemp seed protein powder as a food ingredient and had no questions about its safety.

FAQ

Is hemp protein good for you? It's a nutritious, minimally processed protein with all nine essential amino acids, fiber, and minerals. It's lower in lysine and leucine than whey or soy, and the human research on specific health effects is still small.

Is hemp protein better than whey? For muscle building per gram, whey has the edge in leucine and protein-quality scores. Hemp makes sense if you avoid dairy, want fiber and minerals, or don't get on with whey. Full comparison.

Is hemp protein better than pea protein? They have different strengths. Pea is higher in lysine and leucine, while hemp keeps more fiber and minerals. Hemp vs pea.

Will hemp protein get me high? No. It's made from seeds, which don't naturally contain THC, and Cantein's lab test found none.

Is hemp protein a drug? No. It's a food made from hemp seeds. US federal law excludes hemp from the definition of marijuana, and the FDA has said hemp seed foods can't make you high. THC, the law, and drug tests.

Is hemp protein high in fiber? It varies by brand, from about 2g to 11g per serving. Powders with more fiber have less protein. Cantein Unflavored has 2g; Protein + Fiber has 6g.

Is hemp protein hard to digest? Tested hemp products are highly digestible. Some people still get bloating from any new powder. Start with half a scoop.

Which hemp protein powder should I buy? Brands range from about 43% to 80% protein by weight, and they differ on fiber, origin, price, and whether they publish heavy-metal results. We compared five, including ours: hemp protein powders compared.

Sources

  • House JD, Neufeld J, Leson G. Evaluating the quality of protein from hemp seed products through the use of the protein digestibility-corrected amino acid score method. Journal of Agricultural and Food Chemistry, 2010. doi.org/10.1021/jf102636b
  • Herreman L et al. Comprehensive overview of the quality of plant- and animal-sourced proteins based on the digestible indispensable amino acid score. Food Science & Nutrition, 2020. doi.org/10.1002/fsn3.1809
  • Samsamikor M et al. Hemp seed protein and its hydrolysate compared with casein protein consumption in adults with hypertension. American Journal of Clinical Nutrition, 2024. doi.org/10.1016/j.ajcnut.2024.05.001
  • Mollard RC et al. Acute effects of hemp protein consumption on glycemic and satiety control. Applied Physiology, Nutrition, and Metabolism, 2021. doi.org/10.1139/apnm-2020-0907
  • Neacsu M et al. Hemp and buckwheat are valuable sources of dietary amino acids. European Journal of Nutrition, 2022. doi.org/10.1007/s00394-021-02711-z
  • Kaviani M et al. Effects of hemp supplementation during resistance training in trained adults. European Journal of Applied Physiology, 2024. doi.org/10.1007/s00421-023-05337-7
  • Stadtmauer G et al. Anaphylaxis to ingestion of hempseed (Cannabis sativa). Journal of Allergy and Clinical Immunology, 2003;112:216–217.
  • Decuyper II et al. Cannabis sativa allergy: looking through the fog. Allergy, 2017. doi.org/10.1111/all.13043
  • Linger P et al. Industrial hemp (Cannabis sativa L.) growing on heavy metal contaminated soil: fibre quality and phytoremediation potential. Industrial Crops and Products, 2002. doi.org/10.1016/S0926-6690(02)00005-5
  • NIH Office of Dietary Supplements. Manganese fact sheet (upper limits). ods.od.nih.gov/factsheets/Manganese-HealthProfessional/
  • FDA. FDA responds to three GRAS notices for hemp seed-derived ingredients for use in human food, 2018. fda.gov
  • Callaway JC. Hempseed as a nutritional resource: an overview. Euphytica, 2004. doi.org/10.1007/s10681-004-4811-6
  • Liu FH et al. Ethnobotanical research on origin, cultivation, distribution and utilization of hemp (Cannabis sativa L.) in China. Indian Journal of Traditional Knowledge, 2017;16(2):235–242.
  • Vickery HB. Thomas Burr Osborne, 1859–1929. National Academy of Sciences Biographical Memoirs, vol. XIV, 1931. nap.nationalacademies.org
  • Health Canada. Hemp and the hemp industry: frequently asked questions. canada.ca
  • 21 U.S.C. § 802(16), definition of marihuana, excluding hemp. law.cornell.edu
  • Nutiva Peak Protein and Fiber Plus product pages, checked October 2, 2026: see hemp protein powders compared
  • Cantein nutrition labels: ingredients and nutrition, per scoop