Peanuts: Nutrients, What Research Shows and Safety

The peanut (Arachis hypogaea) is not a tree nut. It is a legume, in the same plant family as beans and lentils (Fabaceae), and the pods grow underground. We eat the seeds inside the shell, and we use them like nuts: roasted, salted, boiled, or ground into peanut butter. People eat peanuts for protein, fiber and minerals, and some hope for heart benefits. This page keeps peanuts as a food apart from oils and supplements, and says where the evidence is thin. It also covers the safety questions people ask most: peanut allergy, babies, aflatoxin and calories.

Read this first

• Peanut allergy is a different allergy from tree nut allergy, because the peanut is a legume. Pediatric reviews often discuss peanut and tree nut allergy side by side, but they are listed as separate allergies. [7] For trouble breathing or swelling of the face or throat, call 911 (or your local emergency number). See nut and seed allergy basics.
• Babies: a large randomized trial found that feeding peanut early to infants at high risk lowered peanut allergy at age 5. Talk to your child's doctor before you start, especially if your baby has severe eczema or egg allergy. This is guidance to discuss with a pediatrician, not advice from us. [3][4]
• Peanuts can carry aflatoxin, a poison made by mold. Buy from sealed, in-date products and throw away moldy or shriveled peanuts. [11][12]
• Whole peanuts are a choking risk for young children. [14]
• Peanuts are energy dense: about 160 calories in an ounce. [1]
• Honest summary: eating nuts, peanuts included, is linked to lower heart disease in large observational studies. That does not prove peanuts cause the benefit. Pooled cholesterol trials we read did not include peanuts. [5][6]

What is in it (USDA values)

USDA data for raw peanuts (all types). The USDA household portion is 1 ounce (28.35 g). [1] USDA lists 1 cup as 146 g and 1 peanut as 1 g. [1][2]

Source: USDA FoodData Central item 172430 (SR Legacy). [1] The per-ounce column is the USDA per-100 g value scaled to 28.35 g. % Daily Value uses the FDA 2016 Daily Values; values vary with variety, growing place, roasting and storage. For dry-roasted peanuts without salt, USDA lists 587 kcal, 49.7 g fat and 24.4 g protein per 100 g (about 166 kcal, 14.1 g fat and 6.9 g protein in an ounce). [2] USDA lists no value for omega-3 ALA in the raw item, and 0.025 g per 100 g in the dry-roasted item, which is tiny. [1][2]

By USDA's numbers, about half of the fat in raw peanuts is monounsaturated (24.4 g per 100 g) and about a third is polyunsaturated (15.6 g per 100 g). [1] We did not read a source that measured or tested other peanut plant compounds in people, so we make no claim about them. One 6-month trial in 63 young adults found that eating peanuts or peanut butter shifted blood fat molecules, and a combined analysis linked that pattern modestly to lower type 2 diabetes risk, partly explained by body mass index. This is a small human study with a lab-style outcome, not proof of benefit. [13]

What research says

Eaten as food vs taken as oil, extract or supplement. The cohort and trial results above are for peanuts or peanut butter eaten as food. We did not read trials of peanut oil or peanut extracts, so we say nothing about them. Observational studies cannot prove cause: people who eat nuts often differ in other habits. We did not see industry funding stated in the abstracts we read, but abstracts often leave funding out.

How much is a normal serving

The USDA household portion for raw peanuts is 1 ounce (28.35 g), and 1 cup is 146 g. [1] That ounce gives about 161 kcal raw or 166 kcal dry-roasted. [1][2] A cup of raw peanuts is about 828 kcal (567 kcal per 100 g x 1.46). [1] This is information, not a prescription. We did not read the MyPlate or FDA qualified-claim text, so we quote no official serving advice here.

Salted, honey-roasted and oil-roasted peanuts, and peanut butter with added sugar or salt, differ from the USDA unsalted figures; check the label. Boiling fresh peanuts lowered fat, sucrose and firmness in a lab study and changed the flavor; it did not measure health effects. [10] Whether weight rises with peanut intake is unclear: the small trials above saw no change, and we found no meta-analysis. [16][17]

Safety, allergy and medicines

• Peanut vs tree nut allergy. Peanut is a legume, not a tree nut. Reviews of peanut and tree nut allergy in children describe causes, prevention (early introduction), diagnosis and treatment for both. [7] A review of pistachio allergy notes that pistachio and cashew allergy are closely linked because their proteins are similar; that is a tree nut link, not a peanut one. [8] We did not read a source on how often people have both allergies.
• How common. A 2026 meta-analysis abstract says peanut allergy affects "2% of children and 1% of adults". [9]
• Emergency. For trouble breathing, swelling of the face or throat, repeated vomiting or fainting after eating peanut, call 911. See food allergy basics and emergency signs.
• Early introduction for infants. LEAP showed less peanut allergy at age 5 in high-risk infants who ate peanut early, with no significant difference in serious side effects. [3] The NIAID 2017 addendum guidelines build on this trial; we could not open the NIAID page, so we do not restate its age and testing steps. Ask your pediatrician. See foods for babies and toddlers.
• Aflatoxin. In a Guangzhou study of 1,179 food samples, roasted peanuts contributed most to estimated aflatoxin exposure, especially in young children, and bulk or market products were more contaminated than pre-packaged foods. [11] A review says aflatoxins account for a substantial share of liver cancer worldwide. [18] Aflatoxin is unevenly spread among kernels and roasting does little to rescue a contaminated lot, so contamination has to be controlled before grinding. [12]
• Choking. In a West Bank study of 292 children with airway foreign bodies, about three-quarters were under 3; seeds were the most common object (41.1%) and nuts the next (10.3%). [14] Whole peanuts are a hazard for young children.
• Oxalate and kidneys. A 2026 review lists peanuts among oxalate-containing foods. [15] We did not read a source linking peanut intake to kidney stones, or a renal-diet limit for peanuts. People with stones or kidney disease can ask their clinician. See foods, kidney disease, potassium and oxalates.
• Medicines. Proper evidence on peanuts interacting with medicines was not found in the sources we read.
• Boiled peanuts. We found no source showing that boiling makes peanuts safe for people with peanut allergy. If you are allergic, avoid them.
• Peanut oral immunotherapy is a medical treatment with real risk of reactions. [9]

Choosing, storing and food safety

• Buy sealed, in-date peanuts and peanut butter; throw away peanuts that look moldy, shriveled or discolored, because aflatoxin is spread unevenly and cannot be judged by eye. [12]
• Bulk and market products had more aflatoxin than pre-packaged foods in one study; this is from China and may not apply everywhere. [11]
• A preprint (not peer-reviewed) from Rwanda found that sealed hermetic storage cut aflatoxin by 57% vs sun drying, and that aflatoxin tracked moisture. [19]
• See the guide on storing nuts and seeds.

Related pages

• Nuts and seeds for heart health: what trials found
• Foods for babies and toddlers: choking, honey and allergens
• Nut and seed allergy basics
• Storing nuts and seeds: rancidity, mold and aflatoxin
• Nut and seed butters
• Legumes