Proteins

Proteins

Proteins are necessary for the growth and maintenance of body protein. The loss of body proteins is related to many diseases and an increase in mortality (death). An adequate protein intake maintains the ability to adapt to different metabolic and environmental conditions (such as periods of physical and mental stress, drastic changes in environmental temperature, diseases, physical stress, pollution, etc.).

Proteins perform many functions in our body: they have structural functions, allow muscle contraction, transport substances in body fluids and between cells, play the role of chemical messengers in biological reactions, act as regulators in the immune system and in several processes of growth, development and cell differentiation.

The sources of protein in our diet are:

Animal Products: 

• Meats such as beef, chicken, fish, duck, pork, deer, etc. 
• In dairy products such as cheese, milk and yogurt. 
• In eggs.

Choose healthy animal proteins 

Such as eggs, fish, skinless poultry, lean meats (low in fat) such as lean pork and lean beef.

Avoid fatty meats and processed meats such as sausages (hams, mortadella, salami, etc.). 

Choose low-fat dairy products such as mozzarella cheese and cottage cheese. 

Avoid cheddar cheese, cream cheese, blue cheese and others with high-fat content.

Vegetable Products: 

Legumes such as: beans (like black beans, white beans, red beans) chickpeas, lentils, peas, soy, tofu, etc. 

Oilseeds such as peanuts, walnuts, hazelnuts, cashew, pistachio, sesame seeds, sunflower seeds, pumping seeds, and others.

High and low biological value

There are proteins of high and low biological value depending on their composition of essential amino acids (proteins are composed of amino acids; we could say that a protein is a house and amino acids are the blocks which the house is built with).

Proteins of animal products are of high biological value since they have all the essential amino acids unlike the proteins of vegetable products that do not possess all the essential amino acids in the same food, so they are proteins of low biological value.

However, by combining 2 types of foods a protein of high biological value is obtained. For example: combining cereals and legumes, or legumes with oilseeds. Thanks to this, people with vegan diets get all the essential amino acids without the need to eat any animal products.

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Avoid to cook your proteins in unhealthy ways like fried, always prefer healthy cooking ways like baked, roasted, grilled, etc. 

Written by:

Roxana Sanchez

Dietitian - Nutritionist

Posted on September 2019 

References

Hernandez, A. G. (2010). Nutrition Treaty Volume I Physiological and Biochemical Bases of Nutrition. Madrid: Pan-American Medical Editorial.

Hernandez, A. G. (2010). Nutrition Treaty Volume II Composition and Nutritional Quality of Foods. Madrid: Pan-American Medical Editorial.

National Institute of Nutrition. (2012). Energy and Nutrient Reference Values ​​for the Venezuelan Population. Caracas: Corn People.

Mahan, K, Scott-Stump, S, & Raymond, J. (2013). Krause Diet Therapy. Barcelona: Elsevier.

Yeon Lim, M, Benyon, S, & O'Neale Roach, J. (2013). The essential in metabolism and nutrition. Barcelona: Elsavier.