What are proteins?
Proteins are composed of 20 amino acids. 9 of them are indispensable, because we can get them only from food, while the rest of the body produces itself if it does not receive it from food.
Proteins in the body perform several important functions: they regulate tissue growth and regenerate them, form muscles, affect the quality of skin and hair, maintain water balance and ensure uninterrupted communication between all the systems in our body. In a 76-pound man, about 12 kg of protein: about 6 kg are found in skeletal muscle, and 1.8 kg in blood and skin.
Proteins are contained in plant and animal food, but only the second can provide our body with all the necessary amino acids. However, do not neglect the vegetable protein food, because it contains a lot of other useful trace elements.
- Fish – a source of omega-3 fatty acids and vitamins of group B (B2, B6, B12, folic acid)
- Red meat contains iron, zinc, vitamin B12, magnesium and monounsaturated fats. Recommendations for meat eaters: Eat red meat 3-4 times a week so that the body gets all the necessary vitamins and trace elements.
- Chicken and turkey contain vitamin B12, iron and zinc.
- Eggs contain monounsaturated fats, lutein and zeaxanthin, which are good for vision. Also in eggs there are a lot of vitamins B12, A, folic acid, iron, iodine and selenium.
- Milk, cheese, yogurt contain calcium, vitamins B2, B12 and phosphorus.
Proteins contained in plant foods are “incomplete,” since they do not contain all the essential amino acids that the body also cannot produce by itself.
Soy protein, which contains all the essential amino acids, is an exception, so almost all vegetarians include tofu in their menu. Another good source of “complete” protein (and undervalued by many) is quinoa. Proteinaceous plant food also supplies the body with other beneficial substances.
For example, legumes are rich in dietary fiber, iron, vitamin B, magnesium, phosphorus, and zinc, and soybeans contain isoflavones (natural analogs of estrogen). Tofu is rich in iron and calcium.
How much protein do we need?
The amount of protein needed by the body depends on age, gender, level of physical activity and body weight. Even if the protein product contains a minimum of this substance, it contains a lot of vitamins and minerals.
Scientists say that from 15 to 20% of the daily value of kcal. we must get from protein foods. Daily intake of protein by men should be 105 g, and by women – 71 g. However, these are approximate figures, which depend on many factors.
Who needs more protein?
During periods of increased growth (in children and adolescents), pregnancy and breastfeeding, in case of illnesses and rehabilitation after operations, the body needs an increased dose of protein. Of course, we all know that with heavy physical exertion, it is also necessary for muscle recovery.
Vegetarians and people of age should pay special attention to the nutritional value of their food and also make a choice in favor of protein.
How much protein is in food?
Every day we need to consume about 81 grams of protein in food. This is about 15% of total calories.
You can console yourself by buying a 120-gram steak, eat 120 grams of protein, but no: meat also consists of water and fat.