Protein: Everything You Need to Know
Protein is one of the three macronutrients vital for sustaining life. It is responsible for your body’s optimal maintenance and overall growth and development. Proteins are complex organic compounds made up of a chain of smaller units known as amino acids — you can imagine it as a long string of beads, in which each bead is an amino acid.
Amino acids can be classified as:
1. Essential amino acids: The body cannot produce these and needs to obtain it from the diet.
2. Non-essential amino acids: The body can produce them.
3. Conditionally essential amino acids: The body requires these during special situations like illness or stress.
Proteins are abundantly found in animal foods and some plant-based foods. Animal sources include poultry, meat, eggs, fish, and dairy products, which provide all the essential amino acids that your body requires.
Plant-based sources include beans, vegetables, grains, nuts, and seeds. They need to be consumed in certain combinations as they often lack one or more essential amino acids. This can pose a problem for vegans, vegetarians and those who are not consuming a diverse diet — which includes foods from different food groups.
Why is protein important?
Protein has numerous essential functions in the body. Let us explore some of them.
Aids in the growth and maintenance of the body
Proteins are required for growth and development and help repair and restore the daily wear and tear of the muscles. They are especially pivotal during specific periods of life such as infancy and adolescence, when peak growth is achieved.
Talking about growth, proteins are most known for the role they play in muscle-building. Muscles are made of protein, therefore the quantity of protein you consume should meet the requirements of your chosen physical activity (~1 -2.2g/kg body weight per day) to initiate muscle protein synthesis, which is what builds muscle.
Gives structural support
Your skin, hair, nails, bones, tendons, and various other body parts are made up of proteins, such as collagen, elastin, and keratin. These proteins are fibrous and add stiffness and inflexibility to cells and tissues.
Apart from these functions, proteins also act as transporters of vitamins, minerals, and antibodies to support your immune system by protecting the body from harmful pathogens, bacteria, and viruses.
Acts as a hormone
We have all heard about hormones and how their imbalance can lead to mood swings, hormonal disorders, weight gain, hair fall, or acne. Well, several of these hormones are nothing but proteins. They transmit signals to coordinate biological processes between cells, tissues, and organs.
Helps with biochemical reactions
When you eat something, chemicals called enzymes work along with the stomach acid and digestive juices to break down food and absorb nutrients. These enzymes are also proteins.
Enzymes are also responsible for speeding up various chemical reactions in the body. Functions such as blood clotting, wound healing, energy production, and muscle contraction are dependent on enzymes. If enzymes don’t function properly, you could fall prey to illnesses.
How much protein should you consume?
According to the Acceptable Macronutrient Distribution Range (AMDR), proteins should provide 10%-35% of total calories that are consumed every day.
Another way to calculate daily protein requirements for sedentary individuals is at the rate of 0.8g-1g per kg of body weight. For instance, a person who weighs 60kg must consume an average daily minimum 48g (60 x 0.8 = 48 g) of protein. This amount can be split between four meals a day, so each meal contains 0.2g of protein/kg of your body weight.
It’s important to note that special conditions like pregnancy or lactation may demand different protein requirements.
What happens if you consume too much or too little protein?
Anything, when taken in deficit or excess, may result in potential health risks. The same holds true for protein. Research suggests that excess protein consumption may lead to weight gain. Additionally, some people may also experience symptoms of constipation, diarrhea, or dehydration, especially in case of sudden increment in dietary protein.
Therefore, it’s wise to keep a check on your total calories and gradually increase the protein quantity. Say, an additional 0.2g/ per kg of body weight to the recommended intake over a span of two to four weeks, would be ideal. This would give your body, especially the digestive system, enough time to adapt to the new change in routine.
On the other hand, consuming protein below the recommended intake may result in deficiencies that may include symptoms like edema (swelling of various body parts), problems related to hair, skin and nails, weakness, low immunity, and slow recovery from injuries.
As you see, proteins are indispensable for sustenance and must be consumed in adequate quantities for the body’s efficient functioning. So, be mindful of getting your protein for an optimal diet.
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