Hemp Hearts Benefits: What They Contain and What Is Proven

Hemp hearts are hulled hemp seeds. This page lists what a serving contains, what those numbers mean, and where the evidence stops. All nutrient amounts come from one USDA record. Percent Daily Values are this site’s arithmetic from FDA’s reference values.

What do hemp hearts contain?

A 30 g serving (3 tablespoons) has 166 calories, 9.5 g of protein and 14.6 g of fat. USDA FoodData Central lists hemp hearts as “Seeds, hemp seed, hulled” and gives 3 tablespoons as 30 g.

Daily Values are from FDA’s Daily Value table for adults and children aged 4 and over. FDA calls 20% or more per serving “high” and 5% or less “low”. The full tables per 100 g and per tablespoon are on the hemp hearts nutrition page.

Protein: 9.5 g per serving

Hemp hearts are 31.6% protein by weight, the highest of the six seeds in this site’s seed nutrition comparison. Pumpkin seed kernels are close at 30.2%.

Quantity is not the whole story. House, Neufeld and Leson (2010) measured protein quality in Canadian hemp products with the PDCAAS method. Dehulled hemp seed scored 63 to 66%, and lysine was the first limiting amino acid in every product.

So the 19% Daily Value above is a simple weight calculation. It does not adjust for protein quality. See hemp seeds protein for the amino acid numbers.

Fats: mostly polyunsaturated, with both essential fatty acids

About 78% of the fat in hemp hearts is polyunsaturated: 38.1 g out of 48.8 g per 100 g. Fat supplies roughly 79% of the calories.

The ratio of linoleic acid to total linolenic acid is 2.75 to 1. USDA’s total for linolenic acid includes gamma-linolenic acid (GLA), which is an omega-6. Counting only ALA, the omega-6 LA to omega-3 ALA ratio is about 3.2 to 1.

Linoleic acid and ALA are called essential because humans cannot make them, according to the Linus Pauling Institute at Oregon State University. The same source gives the adequate intake for ALA, set by the US Institute of Medicine, as 1.6 g a day for men and 1.1 g for women. One serving of hemp hearts contains more than that.

Two limits apply. First, ALA is not EPA or DHA, the omega-3s in fish. The Linus Pauling Institute reports studies in which young men converted about 8% of dietary ALA to EPA and 0 to 4% to DHA. Second, no official body cited here sets a target omega-6 to omega-3 ratio. Some papers call a ratio near 3 to 1 “desirable” or “optimal”. That is the authors’ view, not a tested health outcome.

Minerals: magnesium, phosphorus, zinc and iron

One serving provides 50% of the Daily Value for magnesium and 40% for phosphorus. By FDA’s 20% rule, hemp hearts are high in magnesium, phosphorus and zinc. They are a moderate source of iron at 13%.

The same serving is also high in manganese (99%), copper (53%) and thiamin (32%).

These numbers are what the seed contains, not what the body absorbs. The Linus Pauling Institute notes that phytate in plant foods such as whole grains and legumes inhibits zinc absorption. A 2026 review in the Journal of Food and Drug Analysis lists anti-nutritional substances among the known drawbacks of hemp seed. This site found no human study measuring mineral absorption from hemp hearts.

What is not proven

No human trial shows that eating hemp hearts prevents or treats any disease. The clearest statement comes from a review by Rodriguez-Leyva and Pierce (2010) in Nutrition & Metabolism.

The authors wrote that the effects of dietary hempseed in humans “have only been studied to a limited extent”. They added that cardiovascular prevention trials using hempseed had not been performed. Their conclusion was a hypothesis that deserves more research, not a recommendation.

The human trials they reviewed used hempseed oil, not hemp hearts:

Results were inconsistent, and the samples were small. Claims that hemp hearts lower blood pressure, reduce inflammation, aid weight loss or improve digestion are not supported by trials on hemp hearts that this site could find. More on the oil is on the hemp seed oil benefits page.

Limits and cautions

Hemp hearts are a calorie-dense food with few known risks, but four points are worth knowing.

• Calories. At 553 kcal per 100 g, a 30 g serving has 166 kcal. Three servings a day would add about 500 kcal.
• Low fiber. A serving has 1.2 g of fiber, 4% of the Daily Value. The hull holds most of the fiber. See hemp hearts vs hemp seeds.
• Allergy. Anaphylaxis after eating hempseed was reported in the Journal of Allergy and Clinical Immunology in 2003. In 2022 the AAAAI discussed a child who reacted to a smoothie containing hemp seed. Its expert noted that hemp and cannabis allergy has been described and may cross-react. How common this allergy is has not been established in the sources cited here.
• Contaminants. The 2026 review above names heavy-metal accumulation by the hemp plant as a characteristic hazard. It does not give a safe or unsafe intake for hemp hearts.

Regulatory status in the US

FDA has not objected to hulled hemp seed as a food ingredient. On December 20, 2018, FDA completed its review of three GRAS notices from Fresh Hemp Foods, Ltd. They covered hulled hemp seed (GRN 765), hemp seed protein powder (GRN 771) and hemp seed oil (GRN 778). The agency had “no questions” about the company’s conclusion that they are generally recognized as safe for the intended uses.

FDA also states that hemp seeds do not naturally contain THC. Trace amounts of THC and CBD can be picked up during harvest and processing. FDA says eating these ingredients is not capable of making consumers high. The notices do not cover food with added CBD or THC. For the wider legal picture, see hemp vs marijuana.

How hemp hearts compare with other seeds

Hemp hearts lead on protein and magnesium and trail on fiber. Chia has 34.4 g of fiber per 100 g and flaxseed 27.3 g, against 4 g for hemp hearts, per USDA.

The seed nutrition comparison tool puts hemp hearts next to chia, flax, pumpkin, sunflower and sesame for every nutrient. For the two-way comparison, see hemp seeds vs chia seeds.