Raw or cooked vegetables
It is a well-known fact that vegetables are good and it is important to consume them, but it is not always done correctly: in fact, there are vegetables that are more suitable to be eaten raw, other cooked, and even cooking standards have a fundamental value.
Since we were kids, we have heard that we must eat vegetables and as adults, we became aware of the preciousness of vitamins, minerals, fibers and antioxidants that are contained in them.
Consuming vegetables is an obligatory step to have a healthy and correct nutrition, but this is not enough, since it is essential to do it in the right way.
To make the difference there are two fundamental points: the first one is if a type of vegetable is eaten raw or cooked; the second one is the choice of the type of cooking. Why is it necessary to make this distinction? Aren’t vegetables always good regardless? Well, if we want to take as many present nutrients as we possibly can…not really. Let’s find out why.
Vegetables: why some raw and others cooked?
Vegetables contain different vitamins and various classes of antioxidants that react differently with cooking, increasing or decreasing their bioaccessibility, that is the quantity available for intestinal absorption after being released from the food, and it depends above all on how much and how the food is cooked.
For example, lycopene and beta-carotene are two compounds that we find respectively in tomatoes and carrots or in pumpkin and which increase their availability with cooking, while some vitamins, such as folic acid and vitamin C degrade easily with heat.
There is therefore an important distinction between bioavailability and quantity of a certain nutrient present: to say that 100 g of peppers have 166 mg of vitamin C, for example, does not mean that eating a hectogram of this vegetable effectively you assimilate the total amount of vitamin C, because it depends on the way we cook them.
Let’s see which are the vegetables to be eaten raw or cooked, which in both ways and the reason for these choices, in order to absorb as much nutrients as possible.
Vegetables that should be eaten raw
Below we see vegetables that should be eaten raw to maximize the absorption of the nutrients present. This does not mean that if cooked they hurt, we simply risk losing a good part of the nutrients present.
Lettuce, including all the various types. Digestive and refreshing, lettuce is rich in important mineral salts such as potassium, magnesium, iron, calcium. It is better to be eaten raw for its vitamin C and chlorophyll, powerful antioxidants and antianemics sensitive to cooking, in fact they would be lost with it. Vitamin C, specifically, belongs to the family of thermolabile vitamins, not heat resistant. Boiling in water can result in an average loss of 50% of vitamin C compared to the total content in a common raw vegetable. In the same way, mineral salts are also dispersed if cooked in plenty of water.
Cucumber. With its richness of water and the low intake of calories and fats, cucumber has a strong draining power. It is preferred to consume it raw due to the presence of folate, vitamins C and group B, all thermolabile elements, and for the high presence of potassium and phosphorus. Boiling in water has a highly negative effect on the folate present in common vegetables, causing average losses of 68%.
Rocket has many properties: it is diuretic and antioxidant, antithrombotic, improves intestinal motility and gastric emptying, strengthens the immune system. It is rich of potassium, phosphorus, zinc, iron, calcium, but also vitamin C, K and folate. The consumption of raw rocket ensures all the benefits to the organism.
Vegetables that should be eaten cooked
After seeing which vegetables should be eaten raw, we see below those that should be cooked to improve the bioavailability of nutrients and make them more digestible. In fact, these vegetables, if not cooked, in addition to having a low intake of nutrients, would be very difficult to digest.
Pumpkin. It is a friend of the cardiovascular system, which is also edible by diabetics and a great ally in case of constipation and water retention. The typical orange of the pumpkin is due to the presence of beta-carotene, a carotenoid with pro-vitamin activity since it is a precursor of vitamin A. Beta-carotene increases its bio-accessibility through cooking, especially if steaming or, even better, through boiling. For seasoning, do not forget to add a little oil, since beta-carotene is a fat-soluble vitamin.
Cabbages. Broccoli, black cabbage or cap, cauliflower, brussels sprouts and watercress, they are all vegetables belonging to the cruciferous family and rich in glucosinates, molecules that plants use to protect themselves from any parasites and in humans they perform strong protective and anti-cancer functions. In order not to lose too many glucosinates, we recommend a light pan or steam cooking, using a little water and reducing the cooking time to a few minutes. Some studies have in fact shown how boiling these vegetables can cause a loss of even more than 90% of glucosinolates.
Zucchini. They are highly appreciated for their low calorie content and the numerous fibers that stimulate intestinal regularity. Zucchini are also rich in potassium, vitamins A and group B. They are a good source of carotenoids, especially in the variety with the yellow skin. We recommend steaming for a few minutes to make them more digestible.
Eggplants. They are an excellent concentrate of potassium, phosphorus, magnesium, vitamin A, and have high percentages of water, which make them excellent for facilitating diuresis and having a purifying effect. Like all purple-colored plants, eggplants contain anthocyanins with a strong protective and antioxidant action. A study has shown how grilling these vegetables increases the amount of antioxidants.
Vegetables that can be eaten cooked or raw.
Finally, let’s see those vegetables that should be included in the diet both raw and cooked. This is because they have different characteristics if they are eaten raw or cooked and, therefore, we recommend using them alternately in your diet to optimize the intake of all the nutrients present.
Carrots. They have an excellent content of fiber, minerals (potassium, phosphorus, zinc, calcium) and vitamins (groups B and C) and, above all, they are the main sources of beta-carotene, hence the name chosen for the vegetable. They are diuretic, purifying, with antioxidant properties that help to lower blood cholesterol levels. It is a good practice to vary and alternate recipes using raw or cooked carrots, always adding oil for the dressing, for their important content of vitamin C, thermolabile, and beta-carotene which, on the contrary, is assimilated more after cooking, even prolonged.
Tomatoes. They are rich in water and low in calories and fats, with a discrete vitamin intake given by group B, vitamin C, D and E. They are mineralizing, diuretic, digestive, suitable for diabetics and those who follow a low-calorie diet. Tomatoes contain high concentrations of lycopene, a carotenoid without pro vitamin activity but with a broad antioxidant power. Its bioavailability improves after cooking because the vegetable undergoes tissue shredding and the heat treatment changes the isomeric structure of the molecule, going from a trans to a cis form, more available for absorption. To all this must be added a fat-based dressing such as olive oil, given the liposolubility of lycopene. It is better to choose the alternation between raw tomatoes and cooked tomato sauces in order to be able to extract all the nutrients, as for the carrots.
Peppers. They are satiating, diuretics, antioxidants thanks to the high concentration of water, potassium, phosphorus, fibers, vitamin C, of group B, beta-carotene, and lutein. For many people, raw peppers are indigestible, but it is the best way to stock up on ascorbic acid. As well as for carrots and tomatoes, the option to alternate their consumption from raw or cooked is valid.
Spinach. It is rich in minerals, carotenoids, vitamin C and iron. The presence of ascorbic acid increases the absorption of iron, bypassing the stop given by the chemical form. Cooking spinach increases the availability of carotenoids, while if eaten raw, they will have a higher content of vitamins. If you prefer to eat them after cooking, choose the steamed one, with the addition of a few drops of fresh lemon.
Fennel. It has very few calories (9kcal / 100g), practically zero fat and are abundant in water. Allies of the line for the draining, satiating and carminative action thanks to the fibers and essential oils, fennel can enrich a simple salad thanks to their crunchiness or be enjoyed as a hunger-breaking snack. The high content of vitamin C and potassium means that they are preferable if eaten raw, in terms of nutrients, even if the culinary custom of taking them cooked is very common. In this case, to avoid the dispersion of too many important elements, it is preferable to choose steam or oven cooking, that are more conservative methods.
Asparagus. White, green or violet. Beyond the chromatic difference, asparagus retain all their nutritional characteristics. They are strongly diuretics and purifying, they help to dispose of the tissue stagnation of liquids and to improve kidney activity. They are rich in vitamin C and group B, carotenoids, folic acid, mineral salts such as potassium, phosphorus and calcium. It is advisable to consume them raw to ensure a good supply of folate and ascorbic acid but, on the other hand, not too prolonged steam cooking allows to improve the availability of carotenoids and digestibility. Let’s alternate the consumption between raw and cooked.
How to combine raw and cooked vegetables within meals.
In addition to choose the right way to consume a vegetable, it is important to consider how these side dishes are included in meals and in combination with which foods.
It is a good rule, for example, to start the meal with a portion of raw vegetables: the fibers present in them, in fact, give more satiety, promote digestion and slow down the glycemic peaks by decreasing the absorption of sugars from carbohydrates. Let’s see specifically the best combinations:
Pasta: do we eat a plate of pasta? Let’s avoid a side dish made of cooked starchy vegetables, such as carrots, green beans or fennel: if raw vegetables have diuretic power, cooked ones have a higher glycemic index. We therefore have to prefer a portion of raw vegetables, preferably green leafy;
Meat: raw vegetables are associated with red meat. Salad, fennel, spinach, carrots, radicchio and peppers for example, buffer the acidifying action given by the digestion of proteins and increase the absorption of iron thanks to vitamin C. If you opt for white meat, you can also combine it with cooked vegetables;
Dairy products: dairy products, on the other hand, must be accompanied with cooked vegetables to facilitate intestinal transit and avoid a surplus of minerals that would favor water retention (the classic “caprese” with tomato and mozzarella is so tasty but not optimal nutritionally);
Fish: finally, fish should be better accompanied by raw, uncooked green leafy vegetables.
Cooking vegetables: which one to prefer
The vegetables cooking has the purpose of softening the cellulose present in them, thus making it more easily digestible. There are several ways to cook vegetables, especially if we want to preserve as much nutrients as possible.
Boiling is, in general, “enemy” of vegetables because it involves a massive loss of mineral salts and thermolabile vitamins, except for carrots whose beta-carotene content is made more bioaccessible by cooking, even prolonged, and for the lycopene of tomatoes. The loss is proportional to the size of the pieces (the smaller they are, the greater the dispersion), the amount of water used and the times chosen. The greatest nutrient losses occur with some proteins, certain water-soluble vitamins, especially C and B1, and mineral salts. It is preferable, in general, to choose short boiling times, use a little water or recover the cooking water to drink it later.
Steam cooking is a valid choice, both by using a pressure cooker or by placing a veil of water on the bottom of a normal pot, then keeping the vegetables on a perforated basket, away from the bottom: in this way, you can completely avoids contact with water and the dispersion of vitamins and nutrients. Broccoli, cabbage and cauliflower require 6-7 minutes of cooking; asparagus 6/8 minutes; zucchini 5-6 minutes; spinach 3-4 minutes; peppers 2-4 minutes; carrots 4-5 minutes; eggplants 5-6 minutes.
The grill is also a good alternative for preparing vegetables. In particular, a study has shown that grilling eggplants increases the amount of antioxidants.