Tomatoes: All Properties

Tomatoes are now a very widespread vegetable and have numerous properties and benefits related to their nutritional characteristics, making them an excellent food to be included in the diet, even in weight loss. The tomato ( Solanum Lycopersicum L. ) is an annual herbaceous plant belonging to the Solanaceae family (the same as the aubergine, peppers, and potatoes ). Originally from southwestern, the fruit is from a botanical point of view a berry, has variable shape and size, and is red due to the typical pigment, lycopene.

Tomatoes: Properties And Nutrients

The nutritional properties of the tomato are linked:

  1. its low caloric power and strong satiating effect ;
  2. the low content of basic nutrients (carbohydrates, fats, proteins);
  3. to the richness of minerals that cover up to one-fifth of the daily requirement.

The nutritional value of tomatoes is two to the presence of minerals and vitamins is a major source of vitamin A and especially of vitamin C.

These are associated with the functions of:

  1. ensure the good condition of bones, teeth, and blood vessels;
  2. perform an antioxidant action ;
  3. play a protective role against infections.

Among the minerals are to be mentioned:

  1. The calcium  (11mg per 100g / 1000mg RDAs)
  2. the phosphorus  (26mg / LARN 700mg),
  3. the magnesium  (10mg / LARN 240 mg),
  4. the potassium (290 mg / LARN 3900mg),
  5. the chlorine  (70mg / LARN 2300mg),
  6. The selenium  (2.30μg / LARN55 micrograms)
  7. the iodine  (1.7μg / LARN 150 micrograms),
  8. the manganese  (0.14mg / LARN2.3 mg),
  9. The chromium  (5μg / LARN 25 g).

Water is the main constituent (about 94g per 100g of product). Followed by carbohydrates (3.5g), proteins (1.0g), and fats (0.2g).

Constituent Value (G / 100 G)
Waterfall 94
Carbohydrates 3.5
Proteins 1.0
Fat 0.2

How Many Calories (Kcal) Do Tomatoes Have?

The caloric intake of tomatoes is quite low: just 20 kcal per 100 grams of the edible part or 100% of the food as it is completely edible, and it is not necessary to remove some components as it is necessary to do in the case of other vegetables (e.g., peppers, aubergines).

How Many Vitamins Does It Contain?

Among the vitamins  should be mentioned:

  1. ascorbic acid  or vitamin C (21mg of 100g / LARN 25mg)
  2. pantothenic acid (0.31mg / LARN 5.0mg),
  3. pyridoxine (0.12mg / LARN 1.3mg),
  4. biotin (4μg out of 100g / LARN 30μg),
  5. l ‘ folic acid  (14μg of 100g / LARN 400μg)
  6. retinol (42μg / LARN 600μg),
  7. the tocopherol  (1.03mg / LARN 12mg)
  8. menadione (22.7 μg / LARN 140μg).


Thanks to its lycopene content, this vegetable is characterized by its high antioxidant power. It is a carotenoid that gives the characteristic red color to the ripe tomato. Lycopene is very effective in neutralizing singlet oxygen, one of the most powerful free radicals. It is synthesized at the skin level and is present when the tomato is ripe when its content varies between 43 and 180 mg in the fresh product. 

The peel contains five times more lycopene than the pulp as it is connected with the berry’s fibrous and less soluble portion. Prolonged cooking breaks the chemical structure of lycopene, making it more active at the cellular level and the presence of seasonings (e.g., oil). There is scientific evidence that lycopene can:

  1. reduce the incidence of prostate cancer,
  2. prevent neurodegenerative diseases such as Alzheimer’s,
  3. lower blood cholesterol levels,
  4. have beneficial effects on pancreatitis, gastritis, atherosclerosis, and cardiovascular diseases.

Do Tomatoes Have A Nickel?

Nickel is an environmental contaminant that causes contact dermatitis with the appearance of redness and itching in some people. It is then said that one is intolerant/allergic to nickel. The term allergy is a misnomer because there is no production of antibodies against nickel. It would be more correct to speak of hypersensitivity. Diagnosis is made through a patch test. The test consists of applying a nickel patch to the skin and observing the skin reaction. 

The positivity to the test manifests itself after 24-48 hours with the appearance of an erythematous wheel and indicates the contact sensitivity to nickel. If there is a positive skin test, this does not necessarily mean that there must also be a reactivity towards the nickel contained in food. The absorption of nickel in the intestine is quite low. Most subjects who are also sensitive to skin contact with nickel do not suffer from food hypersensitivity. 

The systemic nickel sensitivity  ( Systemic Nickel Allergy Syndrome, SNAS ) is quite different. It is diagnosed through an oral challenge, namely, orally assuming a certain quantity of nickel (in the form of nickel sulfate). Any reaction is observed, which may be limited to the skin or involve the gastrointestinal system. Nickel is ubiquitous. We find it in soil and water and therefore also in food. This is why a nickel-free diet is practically impossible. At most, you can opt for a low-nickel diet.

Among the strategies aimed at reducing nickel absorption, we mention:

  1. the addition of vitamin C (in the form of lemon juice );
  2. the use of pectins contained in the albedo of citrus fruits and quinces and able to chelate this metal;
  3. the presence of iron in the meal since iron and nickel compete for the same transport molecule in the intestinal mucosa.

Benefits Of Tomatoes: Are They Healthy?

Due to its nutritional composition, the tomato is an excellent food as it contains precious elements which, in a balanced diet context, contribute to maintaining a good state of health:

  1. the high presence of water contributes to the water supply ;
  2. the micronutrients present allow the proper functioning of vital processes ;
  3. the low caloric density make them suitable also in a diet for weight loss and to ensure satiety;
  4. dietary fibers contribute to digestive functions.

However, there are not only benefits: in the unripe tomato, solanine, a substance capable of causing allergic reactions, is well expressed. Solanine is a glycosidic alkaloid present in several plants belonging to the Solanaceae family. Leaves, fruits, and roots contain variable quantities to defend themselves from the attack of fungi and insects. According to the provisions of the FDA ( Food and Drug Administration ), the maximum acceptable content of solanine is 25 mg per 100 g of product. 

The dose considered fatal to humans is 3-6 mg/kg body weight. Green tomatoes can have a solanine content of around 100mg / 100g, and since we don’t cook them, the alkaloid remains intact and can exert its toxic effect once ingested. The most striking symptoms are those affecting the gastrointestinal system and can resemble bad food poisoning. In ripe tomatoes, we no longer find solanine, but alongside lycopene, alpha-tomatine is also a substance capable of exerting a sensitive anti-inflammatory effect. 

Inflammation is a complex biological process that comes into play whenever we have to defend ourselves against pathogens or when we have to repair the tissue damage. The possibility of modulating the inflammatory state through the ingestion of substances normally present in food represents a fascinating area of ​​research. The term ” nutraceutical ” was coined in recent times by the crisis of the two words “nutrition” and “pharmaceutical.” Alpha-domain is, in effect, a nutraceutical substance.

It is a saponin with anti-tumor, anti-viral, and anti-inflammatory power. Several studies have demonstrated the ability of alpha-tomatine to interfere with the metabolic activity of cancer cells in prostate cancer by inducing programmed cell death ( apoptosis ). Therefore alpha-tomatine and lycopene can act synergistically in preventing prostate cancer, and it is interesting to note that these two substances are found within the same food.

Practical Advice On Using Tomatoes In The Diet

Tomatoes are best consumed when they are in season (late spring and summer), such as a vegetable for lunch or dinner. The classic guideline portion is 200 g, equal to 2-3 tomatoes. They can also be used as gravy. The ideal recipe is a sauce prepared with tomatoes of a beautiful deep red because they ripened on a sunny field in August. 

Once finely chopped, tomatoes must be simmered for at least six hours. This is the procedure used to prepare the ragù of our culinary tradition. The use of extra virgin olive oil and abundant spices enhances the anticancer action. But suppose there is no time to prepare our vegetable ragù, even before thinking about taking lycopene and alpha-tomatine in the form of supplements. In that case, it is worth starting to use triple tomato concentrate. It is a veritable mine of antioxidant molecules.


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