Carbohydrates, also known as carbohydrates (from the Greek ‘glucos’ = sweet) are substances made up of carbon and water and are mainly contained in foods of plant origin. The food group that contains them in the greatest quantity is cereals. Carbohydrates are an excellent source of energy for the body as they provide the glucose that is indispensable for the most important life functions.
Three main categories of carbohydrates can be recognised in food:
- sugars, which are simple carbohydrates found naturally in fruit, vegetables, milk and dairy products. The most common sugars are fruit sugar (fructose), table sugar (sucrose) and milk sugar (lactose)
- starch, which are complex carbohydrates consisting of many sugar units bound together. Starch is found naturally in cereals, potatoes and legumes.
- fibres, i.e. complex carbohydrates found naturally in fruit, vegetables, whole grains and legumes that our body is unable to use for energy purposes, but whose fermentation in the intestines contributes to the maintenance of the bacterial flora and is essential for regulating the absorption and passage of nutrients and protecting our bodies from numerous diseases.
In the collective imagination, it is often thought that carbohydrates should not be eaten in the evening, because they lead to gaining weight.
This ‘myth’ is based on two main factors:
- the first factor is metabolic in nature, i.e. carbohydrates consumed in the evening hours would cause an increased susceptibility to hyperglycaemia, bloating, their transformation into fat and an increase in body weight and, in addition, would create difficulties in resting.
- The second is hormonal in nature, i.e. hyperglycaemia due to the introduction of sugar would inhibit the peak of growth hormone (GH) during the early hours of sleep. GH is antagonistic to carbohydrates in that it drives the cell to utilise lipid metabolism.
Both grounds are in fact unfounded:
- energy expenditure during sleep is virtually the same as during low-impact activities, such as sitting at a desk or bench. Thus, if one performs sedentary work, the variations in energy are not so significant as to justify the daily distribution of carbohydrates.
- hormonal variations are not so significant in radically changing body composition.
Speaking of benefits, however, including carbohydrates at dinner stimulates the secretion of tryptophan, the precursor of serotonin and the sleep hormone melatonin. The right portion of carbohydrates at dinner, therefore, promotes a good restful sleep and is also well digestible. Moreover, after 6 p.m., carbohydrate consumption is associated with increased leptin production the next day. Leptin is an essential hormone for keeping the metabolism active and is also a substance that suppresses the sense of hunger.
Another important factor to take into account is training.
In fact, if you train in the afternoon/evening, dinner becomes the best time to consume a carbohydrate quota. This is because training affects insulin sensitivity, which remains high in the two hours following exercise, in order to restore glycogen stores and create an anabolic cellular environment that stimulates protein synthesis.
For a healthy and correct diet, rather than focusing on the role of carbohydrates at dinner, it is necessary to pay attention to how many and which carbohydrates one consumes during the day, also starting from the specific situation in which one finds oneself.
In general, in the evening, it is better to favour whole-grain carbohydrates that are rich in fibre, which slows down the absorption of glucose in the intestine, keeping blood glucose constant for long periods. Therefore, go for whole-grain pasta and bread or cereal grains rich in fibre, such as barley, oats, spelt and buckwheat, as well as legumes such as beans, peas and chickpeas.
To allow for better digestion and adequate absorption of nutrients and to reduce the glycaemic peak, it is also advisable to combine carbohydrates with a small portion of fats, preferably vegetable fats, and proteins, especially from fish or legumes.
Here are some examples for dinners:
- wholemeal pasta with rocket and cashew pesto, baked mackerel fillet with pumpkin
- pumpkin and spiced chickpea soup with cabbage and apple salad
- velvety leek and pea soup with salmon steak and wholemeal bread croutons
- chickpea and turkey meatballs with truffled mushrooms
We can therefore state that carbohydrates in general do not necessarily make one fat, and this does not change depending on when they are consumed: one gets fat mainly because of an excess of calories introduced and an incorrect distribution of nutrients in relation to the body's needs.
(Article by Dr. Giulia Daniotti)
