What is nuts?

Nuts is one of the many names used to indicate oily achenes produced by different plant species. Also commonly called dried fruit, not to be confused with dehydrated fruit, these foods are today considered a valid ally against metabolic pathologies ; in the section on nutrition we will find out better why.

The nuts can be divided into local and imported.

  • Local nuts: walnuts, hazelnuts, almonds, pistachios and pine nuts.
  • Imported nuts: peanuts, Brazilian nuts, pecans, cashews, macadamia.

Note : Smaller seeds, such as pumpkin, sunflower, flax, etc. should also be included in the dried fruit group. However, compared to those already mentioned, they have a slightly different food consumption. They rarely constitute stand-alone foods and are used above all to enrich other recipes such as: breakfast cereals, salads, breads and analogues etc. On the contrary, nuts represent in themselves a food that can be eaten alone, for example as a snack.

Nutrition

Nutritional characteristics

Nutritional role of nuts

These products do not belong to a specific food group. Botanically speaking, they are considered "fruits" and "seeds"; however, in the context of the 7 fundamental food groups (nutritional classification), nuts do not find a precise location.

The fruits (fleshy like drupes, berries, false fruits - group VI and VII) are rich in water, fructose, potassium, vitamin C and carotenoids; for "seeds" we mean mainly starchy ones, ie cereals, pseudocereals and legumes (group III and IV).

All the characteristics listed above are foreign to nuts, which uses a high percentage of fat and contains excellent levels of fat-soluble vitamins and different minerals; not by chance, from most oil seeds it is possible to obtain an edible oil (usually quite valuable).

Note : the only feature that all these foods have in common is the dietary fiber content.

Calories of nuts

The nuts generally have a very high energy intake, which varies approximately from 550 to almost 750 kcal / 100 g. The lipid fraction contributes to almost all of the caloric intake, followed by a significant dose of protein and negligible amounts of carbohydrates.

The caloric density of nuts requires a moderate consumption.

The Italian guidelines advise not to exceed 30 g per day, a quantity that is already very important in itself, as it provides about 8-9% of the total fat requirement. In order not to "siphon off" other food sources of lipids (for example, seasoning oil), it may be reasonable to reduce the portion to 15 g / day.

Nuts of nuts

The composition of fatty acids is variable, but almost always of good nutritional value. In fact, nuts is an excellent source of so-called "good fats", ie those that have a positive impact on the general state of health. Most of them are unsaturated fatty acids, including both monounsaturated (especially omega 9, particularly oleic acid) and polyunsaturated fats; of the latter category we mention the two essential linoleic acid (and derivatives), essential omega 6, and alpha linolenic acid, essential omega 3. The effects of essential fats on the body, especially in the case of pre-existing metabolic disorders, can be summarized as follows:

  • Reduction of total cholesterol
  • Reduction of LDL cholesterol
  • Triglyceridemia reduction
  • Normalization of arterial pressure
  • Reduction of systemic inflammation
  • Reduction of complications related to chronic hyperglycemia, typical of type 2 diabetes mellitus
  • Blood fluidification
  • As a consequence of the effects already described, reduction of the incidence of atherosclerosis and thrombosis
  • Maintenance of structure and nervous and ocular integrity
  • Benefits on mood and brain activity.

Proteins and carbohydrates from nuts

The nuts contain a variable percentage of simple proteins and glucides. Some believe it can be a good source of amino acids; however, due to the high energy power, it must be taken in portions so small that it does not significantly affect the daily protein balance. The same goes for carbohydrates.

Some exponents of this category, such as hazelnuts, peanuts and walnuts, are rich in arginine. This amino acid has many functions, for example, it acts as a precursor of nitric oxide (vasodilator that fights hypertension) and of creatine; besides it is immunostimulant etc. However, it has not been shown that nuts exercise these functions on the body.

Nuts vitamins

The nuts also have an excellent vitamin content. There are both hydrosoluble molecules of group B and lipophilic nutrients. Among the most abundant B vitamins include B1 (thiamine), B2 (riboflavin) and B6 (pyridoxine).

In the group of liposoluble molecules, the most important factor is certainly vitamin E or alpha-tocopherol. Because of its "delicacy", it is a nutrient that is quite difficult to eat with the right amount of diet; it is negatively affected by oxygen, free radicals, light and heat, which is why it is one of the first nutrients to be negatively affected by conservation. In the body, vitamin E effectively combats cellular aging and acts positively on risk factors related to the increase in cardiovascular risk.

Some exponents of nuts contain vitamin and provitamin A and vitamin D, but in not too interesting percentages.

Nuts of minerals

The nuts contain high concentrations of minerals; some are quite common (such as phosphorus, calcium and potassium), while others are considered more difficult to take in the right quantities. With regard to the latter category, the levels of zinc and selenium, minerals with antioxidant function, supporting the thyroid and participating in the integrity of the skeleton are worthy of note. The concentration of magnesium, an alkalizing mineral often lacking in the body of the athlete, is also excellent.

Other nut antioxidants

The nuts do not only contain vitamin and mineral antioxidants, but also flavonoid polyphenols and coenzymes (especially Q10), which further participate in improving metabolic parameters and decreasing cardiovascular risk.

Kitchen

Tips for buying and storing nuts

As we have already said, the nuts can be local or foreign. Brazilian nuts, pecans, cashews and macadamias available on the market are necessarily imported. Moreover, due to the much lower cost, but at the expense of the quality level, walnuts, hazelnuts, almonds, pine nuts and pistachios can also come from abroad.

Due to the production, storage and transport regulations, the nuts coming from certain corners of the world are not qualitatively comparable to the Italian one. In the past, due to the hepatotoxic mold contamination, certain imported oil seeds have also caused serious health problems for consumers. Today, the controls are much more rigid and the risk of intoxication is decidedly low; however, the disadvantage of the lower overall quality remains.

Many people do not know that, despite the high shelf life, even the nuts are subject to aging. This is why it is advisable to especially prefer the seasonal one, avoiding the purchase in the other months of the year.

Dried fruit does not require refrigeration; however, it should be stored in a cool, dry place.

Note : if breaking the shell you can see traces of white, greenish or black mold, it is necessary to avoid eating the food.