Why Protein is Essential

:Protein is crucial to good health as they are the building blocks of life and every cell in the human body contains protein. Our bodies need protein from the foods that we eat in order to build and maintain bones, muscles and skin.  Proteins are made out of smaller molecules called amino acids, which are linked together like beads on a string. These linked molecules form long protein chains which are folded into different intricate shapes. Some amino acids are produced by the body while others are considered “essential” and must be obtained through your diet. There are 20 amino acids that help form the thousands of different proteins in your body. There are many ways in which our body utilizes protein, including some of the following:

• For growth and maintenance
  • Your body’s proteins are in a constant state of turnover and therefore your body needs protein for growth and maintenance of tissues. Under normal circumstances, your body breaks down the same amount of protein that it uses to build and repair tissues. Other times, your body breaks down more protein than it can create, thus increasing your body’s needs. Illness, pregnancy, breastfeeding, recovery from an injury or surgery, older adults and athletes are examples of when a person requires more protein (1).
• To cause biochemical reactions as enzymes
  • Enzymes are proteins that aid in thousands of biochemical reactions that take place within and outside of your cells. Enzymes combine with other molecules (which include vitamins and minerals) to make the reactions take place. Examples include digestive enzymes like lactase and sucrase. Digestion, energy production, blood clotting, and muscle contraction are all bodily functions that depend on enzymes (1).
• Aid in communication between cells, tissues and organs
  • The chemical messengers that aid in this communication are hormones, which are proteins that are made and secreted by endocrine tissues or glands and transported in the blood. Hormones can be grouped into 3 main categories - protein and peptides, steroids and amines. Protein and polypeptides make up most of your body’s hormones and two of the most recognized include insulin and glucagon (1).
• To provide structure
  • Some proteins are fibrous and provide cells and tissues with stiffness and rigidity. These include keratin (found in skin, hair and nails), collagen (most abundant in the body and structural protein of your bones, tendons, ligaments and skin) and elastin (found in many tissues of the body and is incredibly flexible - allowing tissues to return to their original shape after stretching or contracting, such as your uterus, lungs and arteries) (1).
• Helps maintain proper pH balance
  • Proteins act as a buffer system. An example is hemoglobin - it binds small amounts of acid, helping to maintain the normal pH value of your blood. Other buffer systems in your body include phosphate and bicarbonate (1).
• Regulates body processes to maintain fluid balance
  • Albumin and globulin are proteins in your blood that help maintain your body’s fluid balance by attracting and retaining water and if you do not eat enough protein, your levels of these proteins eventually decrease and can lead to negative health effects (1).
• They help form antibodies to fight infection
  • Antibodies are protein in your blood that help protect your body from harmful invaders like bacteria and viruses (1).
• To transport and store nutrients
  • Transport proteins carry substances throughout your bloodstream and into cells, out of cells or within cells. Protein transporters are specific and therefore only bind to specific substances. Proteins, such as ferritin and casein, also have storage roles (1).
• Supply the body with energy
  • Carbohydrates and fats are the first lines of energy, but protein can serve as a valuable energy source during situations of fasting, exhaustive exercise or inadequate calorie intake. Protein contains 4 calories per gram and in a state of fasting (18-48 hours of no food intake), your body breaks down skeletal muscle into amino acids so that you have energy (1).

 
As previously mentioned, some amino acids are produced by the body while others must be obtained through the diet and are therefore considered “essential”. “Nonessential amino acids” are made by the body from essential amino acids or in the normal breakdown of proteins and “conditional amino acids” are needed in times of illness and stress (2).
 
The right amount of protein for any one individual depends on many factors, including activity level, age, muscle mass, goals and current state of health. Animal products such as meat, fish, eggs, and dairy provide provide essential amino acids, but other sources of protein also include:

• Quinoa, amaranth, spelt and teff (ancient grains); sprouted grains
• Legumes (lentils, split peas, beans)
• Nuts and seeds
• Soybean foods (tofu, tempeh and edamame)
• Nutritional yeast
• Seitan (a mock meat made from wheat gluten)

 
It is great to get your protein from a variety of sources as that also increases the variety of other beneficial nutrients as well! Try switching up your protein sources - maybe even create a “meatless” day where you obtain your protein from plant sources that day. Experiment and have fun!
Sources:

1. https://www.healthline.com/nutrition/functions-of-protein#section3
2. https://medlineplus.gov/ency/article/002467.htm
3. https://medlineplus.gov/dietaryproteins.html
4. https://www.healthline.com/nutrition/protein-for-vegans-vegetarians#section15
5. https://www.healthline.com/nutrition/functions-of-protein#section3​

By ​Meghan Rittmaster, RDN, LD
Mackenthun's In-Store Dietitian