On the basis of the high fat content of nuts, they are traditionally considered as foods that provide a high amount of energy. However, epidemiologic and clinical observations do not indicate an association between nut intake and increased BMI. There is a notorious variability in macronutrient composition among nuts, although they have some consistent patterns. Nuts contain all major macronutrients: protein, carbohydrate, and fat. The total protein content is relatively high, which makes them a good source of plant protein (especially for vegetarians). Although nuts contain low amounts of some essential amino acids, this is not a nutritional concern due to the complement of protein. In addition, nuts have a low lysine:arginine ratio, which is inversely associated with the risk of developing hypercholesterolemia and atherosclerosis. Carbohydrates are the second highest macronutrient in nuts in terms of total calories provided. The fat fraction is characterized by a high amount of unsaturated fatty acids and a low content of saturated fatty acids. In conclusion, the high content in unsaturated fatty acids, the low lysine:arginine ratio, and the presence of other bioactive molecules (such as fibre, phytosterols, vitamin and other antioxidants, and minerals) make the addition of nuts to healthy diets a useful tool for the prevention of cardiovascular heart diseases.As we define them today, tree nuts (almonds, Brazil nuts, cashew, hazelnuts, macadamia nuts, pecans, pine nuts, pistachios and walnuts) originate from Anatolia. From there, the cultivation of tree nuts was introduced in Greece, then in Italy during the Roman Empire, and finally it was extended to all of Europe during the Middle Ages. The growing of tree nuts was introduced in America in the 16th century (Lemoine, 1998). Nuts are part of the Mediterranean diet, although their per capita consumption is relatively low (2-9 kg/year). Traditional Mediterranean nuts include almonds, hazelnuts, walnuts, peanuts and pistachios. Typically in Mediterranean diets, nuts are incorporated into many dishes, such as snacks (roasted and salted almonds, hazelnuts, and pistachios), sauces ('romesco' and 'pesto'), cold soups, such as 'ajoblanco' in Spain, cakes, pastries, and cookies ('turrón', 'nougat', walnut cakes, 'menjar blanc', 'amaretti'). Because of their high-energy content, nuts have been introduced into sports snacks and supplements.With today's busy lifestyles, nuts are a convenient, tasty and easy snack that contributes to a healthy lifestyle. In addition to their tastiness, tree nuts and peanuts are both cholesterol-free and rich in important nutrients, including vegetable protein, fibre and unsaturated fatty acids. They also contain relevant micronutrients, such as folic acid, niacin and vitamins E and B 6 , and minerals such as magnesium, copper, zinc, selenium, phosphorus and potassium.Nuts are part of the US Food Guide Pyramid and Mediterranean Diet Pyramids. Experts recommend eating a variety of foods from the five food groups every day in order to obtain ...
