Hazelnuts

In this Article (Index)

• Hazelnuts
• Health Benefits
• Risks: Allergies
• Nutrients and Bioactive Compounds.
• Phytochemicals
• Vitamins
• Minerals
• Oils and healthy fats
• Fiber
• Closing Comments

Hazelnuts

The common hazel or Corylus avellana is native to Europe and Western Asia. It is a shrub of the Betulaceae family, related to the birch. It can reach a height of over 25 feet (8 m).

Chilean hazelnut or Gevuina avellana was named so by the Spanish conquistadors in the mid 1500s-because it resembles the European hazel. It belongs to a different genus.

It produces an edible tree nut shaped like an oval or sphere up to 3/4 inch long (20 mm) and a similar section. The nuts are eaten raw, roasted, or milled into an oily paste. Its dark brown skin has a bitter taste and is sometimes removed before use.

Global production of hazelnuts is roughly 0.86 million tons.

Health Benefits

Eating hazelnuts is good for your heart. The mechanism by which these nuts improve health is their nutrients: unsaturated fats, dietary fiber, vitamins, especially vitamin E, and minerals, especially potassium. Nuts contain unrefined carbohydrates and are low in sodium. (5)

A 2022 meta-analysis (6) supports this assumption, reporting that eating 29 to 69 g per day of hazelnuts lowers the risk of cardiometabolic disease: "significant reduction in low-density lipoprotein (LDL) cholesterol...Total cholesterol showed a marked trend toward a decrease... and high-density lipoprotein (HDL) cholesterol remained substantially stable." Eating more hazelnuts didn't modify triglycerides or BMI (Body Mass Index) (loss or gain of weight).

In conclusion, a hazelnut-enriched diet decreases low-density lipoprotein cholesterol (LDL-C) in a significant way and shows a trend toward reduction of total cholesterol, without decreasing high-density lipoprotein cholesterol (HDL-C); while triglycerides and body mass index (BMI) remain substantially unchanged. These data show a potentially favorable effect on cardiovascular disease (CVD) prevention Perna et al., (2016)(6)

Risks: Allergies

Tree nuts are one of the Big Eight food groups responsible for over 90% of food allergy cases in the US. The other seven allergy-causing foods are peanut, milk, shellfish, soy, wheat, egg, and fish.

Hazelnuts together with peanut allergies are usually more severe and life-threatening than the allergic reactions caused by eggs, or milk, which are normally mild and short-lived. (1)

Eating hazelnuts provokes an increased immune sensitization by immunoglobin E (IgE) in susceptible subjects. (3)

Hazelnut can trigger allergic reactions that range from minor (itching in the mouth, and tongue) to severe (anaphylactic shock; hives and swelling of the throat, asthma) and even death. (4)

Take care, allergic reactions can be very serious

Check the food label for the listed allergens ("may contain...", and "Contains..."), it should mention tree nuts (for example: almonds, cashews, pistachios, pecans, walnut, hazelnut) and peanuts (also called ground nut by some). The American FDA also requires the specific identification of tree nuts such as coconut, shea nut, and pine nuts. Also check the "processed" text which could read: "processed at a facility that handles nuts".
When in doubt, avoid the product, and always read the label for ingredients and the text in the "Precautionary allergen labeling" (PAL). Eating out: Ask the waiter questions.

Nutrients and Bioactive Compounds

• Phytochemicals
• Vitamins
• Minerals
• Oils and healthy fats
• Fiber

Phytochemicals

Phenolic Compounds

As with all nuts, hazelnuts contain antioxidant compounds (polyphenols) with a preponderance of catechin, epicatechin gallate, and gallic acid. (2)

Vitamins

Hazelnuts are especially rich in vitamin E. The following table shows the content of vitamins in mg per 100 grams (for vitamin A it is International Units -IU). (2)

Minerals

Below are some minerals found in hazelnuts (in mg per 100 grams). (2)

Oils and healthy fats

Hazelnuts have the highest content of oils and fats than any other tree nut: 59.8 to 61.5%.
The fats in hazelnuts are mainly monounsaturated fatty acids or MUFA (80%) with oleic acid as its main individual component. Polyunsaturated fatty acids or PUFA represent 15% of the total fat content, mainly linoleic fatty acid. Hazelnuts have a low content of omega-3 linolenic fatty acid.
Saturated fats are mostly palmitic acid. (2),(3)

The following table shows the fatty acids found in these nuts (g/100 g nut)

Fiber

Hazelnuts are rich in dietary fiber, with values ranging from 6.5 to 9.7%. (2)

Closing Comments

Hazelnuts are a healthy nut to add to your diet as their antioxidants, healthy fats, fiber, vitamins, and mineral content have beneficial health effects.