Hickory Nuts: Nutrients, What Research Shows and Safety

Hickory nuts are the kernels of hickory trees in the genus Carya, such as shagbark hickory (Carya ovata) and shellbark hickory (Carya laciniosa). The pecan is a close relative from the same genus (Carya illinoinensis). They are a tree nut: the part eaten is the kernel inside a hard shell. This page covers hickory nuts as a food, keeps them apart from oils and supplements, and says plainly that we found no human research on them.

Read this first

• Hickory nuts are a tree nut. Tree nut allergy can be life-threatening and is outgrown in fewer than 10% of cases. [3] For trouble breathing or swelling of the lips, mouth or throat, call 911 (or your local emergency number). [4][5]
• We found no study of hickory nut allergens, so we cannot say how closely they match pecan or walnut. People with a tree nut allergy should ask an allergist first. [3]
• Whole or chopped nuts are choking hazards for young children (CDC). [7]
• Hickory nuts are energy dense: about 186 kcal in one ounce (28 g). [1]
• Evidence in short: Proper evidence not found in the sources we read for hickory nuts eaten as food in people. Lab work exists on a related species (Chinese hickory) only. [2]

What is in it (USDA values)

Source: USDA FoodData Central, "Nuts, hickorynuts, dried" (FDC 170177). [1] The USDA household portions are 1 ounce (28.35 g), 1 nut (3 g) and 1 cup (120 g), so an ounce is roughly nine nuts. USDA lists no value for vitamin E or ALA in this item. % Daily Value uses the FDA 2016 Daily Values; values vary with species, growing place, roasting and storage.

USDA lists about 32.6 g of monounsaturated and 21.9 g of polyunsaturated fat per 100 g, which is most of the fat. [1] We did not read a source that measured plant compounds in shagbark or shellbark hickory kernels, so we describe none. A 2014 lab study of the kernel oil of Chinese hickory (Carya cathayensis, a different species) found about 70% oil, about 80% unsaturated fatty acids and some free-radical scavenging in test-tube assays. [2] That is lab-only evidence on another species and does not show a benefit from eating hickory nuts.

What research says

Eaten as food versus other forms. The tree nut trials used whole nuts as food. The only hickory-specific research we found tested an oil from a different species in the lab. We could not see funding statements in the abstracts we read. An observational link (people who eat nuts are healthier) is not proof that nuts caused it.

How much is a normal serving

The USDA household portion is 1 ounce (28.35 g), about 186 kcal. [1] This is the figure from the USDA file, not a prescription. How much to eat is a choice for you and your clinician or dietitian. USDA values are for dried hickory nuts; roasted, salted or coated nuts differ, so read the label. Hickory nuts are mostly gathered from wild or small-scale trees and sold in small amounts; we do not cover foraging or shelling them here.

Safety, allergy and medicines

• Tree nut allergy. The NHS lists tree nuts, with walnuts and pecans named as examples, among foods that can cause allergy; symptoms include hives, swelling of lips, face and eyes, wheezing, and they can start right away or days later. [4] MedlinePlus says tree nut allergies tend to last a lifetime, and severe reactions can start right away or within two hours. [5] See nut and seed allergy basics.
• Pecan, walnut and other nuts. A review says walnut and pecan are highly cross-reactive and that the current guideline after one tree nut allergy is strict avoidance of all tree nuts; the extent of cross-reactivity among other tree nuts is unclear. [3] We found no study that tested hickory nuts, so any link with pecan is not shown by the sources we read. An allergist can say which nuts you can eat.
• Labels. Under U.S. law the type of tree nut (for example almonds, pecans, walnuts) must be declared on food labels. [6] Since January 2025 FDA guidance no longer lists hickory nut among the tree nuts for labeling, so a product with hickory nuts names them in the ingredient list but not necessarily in a "Contains: tree nuts" statement. [10] Pecan, a close relative, is still on the list.
• Emergency. For wheezing, trouble breathing or swallowing, or swelling of the face, lips or tongue after eating, call 911 or your local emergency number; use prescribed epinephrine first. [5]
• Choking in young children. The CDC lists whole or chopped nuts and seeds as choking hazards for young children. [7] See foods for babies and toddlers.
• Calories. One ounce is about 186 kcal. [1] Pooled nut trials found no significant weight gain with nut-enriched diets. [9]
• Medicines and kidneys. We did not find a source we could read about medicine interactions or kidney-diet limits for hickory nuts, so we make no claim either way. A pharmacist can check. See foods and medicine interactions.

Choosing, storing and food safety

• We did not read an official source on rancidity or mold in hickory nuts. For storage, mold and aflatoxin basics, see storing nuts and seeds.
• Check the label for added salt, sugar or flavorings and for allergy warnings about shared equipment.

Related pages

• Pecans
• Walnuts
• Nuts and seeds for heart health: what trials found
• Food allergy basics and emergency signs
• Foods for babies and toddlers