Properties of hazelnuts
Nuts are a type of snack that is rich in nutrients, including essential fatty acids, protein, dietary fiber, tocopherols, phytosterols and phenolic compounds. The US Food and Drug Administration (FDA) recommends consuming 42 grams (1.5 ounces) of nuts per day (almonds, hazelnuts, walnuts, pine nuts, pistachios, pecans and peanuts) as part of a healthy diet. In 2016, the European Society of Cardiology (ESC) reported that consuming 30 grams of nuts (walnuts, hazelnuts, almonds) per day reduces the risk of heart and vascular disease (e.g. coronary artery disease). Naturally, they should be unsalted nuts.
An additional confirmation of the nutritional value of nuts can be, among others: nutritional recommendations created by the Food and Nutrition Institute in Warsaw, the Mediterranean food pyramid, the concept of the Healthy Eating Plate.
Fat in nuts
Among natural plant products, nuts are one of the richest sources of fat, and at the same time the composition of fatty acids is beneficial for health thanks to the low (6 - 26%) content of saturated fatty acids (SFA). The rest are mono- (MUFA - monounsaturated fatty acids) and polyunsaturated (PUFA - polyunsaturated fatty acids).
Carbohydrates in nuts
Carbohydrate consumption which provides 55% to 75% of energy is recommended by WHO and FAO experts. In recommended 42 grams of nuts we provide only 1 - 2.5% of energy from carbohydrates and <1% of energy from simple sugars in the 2000 kcal diet, therefore nuts are not a rich source of energy from carbohydrates or simple sugars.
Protein in nuts
Nuts are also a good source of protein. According to WHO and FAO recommendations, protein should cover 10-15% daily energy requirements. Consuming a handful of nuts provides 3-10 g of protein. These is up to 15% for men and up to 19% for women of energy requirements from protein. Moreover, nuts have a low lysine to arginine ratio, which is inversely proportional to the risk of developing hypercholesterolemia and atherosclerosis.
Mineral compounds in nuts
Nuts are also a rich source of a vast number of minerals. 100 grams of some nuts can cover all or the vast majority of the daily requirement recommended for elements like for example iron, magnesium, phosphorus or zinc. The level of sodium in the unprocessed nuts is very low. This can be an advantage for building specific types of diets, e.g. for people with hypertension or kidney failure. Hazelnuts are not a source of sodium.
Vitamins in nuts
The recommended 42 g of nuts provides on average up to 20% of the recommended daily intake of an adult human for vitamins from group B (except for vitamin B12). Nuts are a rich source of thiamine (vitamin B1), vitamins B6, E, and some, especially pine nuts, contain significant amounts of vitamin K. An excellent source of Vitamin E are hazelnuts and almonds. Serving size (42 g) provides over 100% of the recommended daily allowance of an adult male. These amount protects body against free radicals preventing, among the others, aging processes, the development of atherosclerosis or neoplastic diseases.
Antioxidants in nuts
Plant-based food, including nuts, is a rich source of compounds with antioxidant properties. Tocopherols (vitamin E) are considered to be the most important natural antioxidants contained in nut oils. They support fat stability, hence their presence in nuts is desirable, both nutritionally and technologically. Hazelnuts contain vitamin E in the form of α-tocopherol, which shows the most effective preventive activity against coronary diseases. The sterols found in the nuts lower cholesterol level. The mechanism of these compounds action is lowering cholesterol absorption by replacing it with micelles in intestines.