The food we eat can broadly be broken down into three ‘macronutrients’ – proteins, carbohydrates, and fats. A healthy diet needs to consist of an appropriate mix of these nutrients from a variety of sources. Aside from the essential omega 3 and omega 6 fats, our body largely utilizes carbohydrates and fats for energy. Dietary protein, however, is absolutely essential for good health. This is because while protein can technically be used as a source of energy, it has a number of vital structural and functional roles:
- All the muscle, cartilage, ligaments and bone in our body is almost entirely made up of proteins. The structure of our skin and hair is almost entirely made up of the proteins collagen and keratin respectively.
- Our body carries out various tasks such as digestion, blood clotting and nerve signalling through enzymes, which are basically specialized proteins.
- The antibodies our immune system makes to fight infections are proteins which recognize harmful microbes.
- Our blood is almost entirely made up of proteins. Haemoglobin is a specialized protein that carries oxygen across our body.
- A number of vital hormones, such as insulin, are proteins.
- Dietary protein helps regulate appetite and increase satiety.
- Adequate protein consumption helps our body recover from exercise and trauma.
Given the absolutely vital role various proteins play in our body, it is a cause for concern that the Indian Dietetics Association (IDA) has claimed that 84% of vegetarian and 65% of non-vegetarian Indian diets are protein deficient, largely because of the digestibility of protein being consumed. Recent research on the body composition of Indians has shown that 7 out of 10 individuals in the 30-55 year age group have low muscle mass and a high-fat mass.
Addressing these issues is as simple as consuming protein from quality sources, in the right amounts.
The amount of protein an individual needs is a frequently debated topic. A bulk of the information available focuses on the protein required for specialized populations, such as athletes and bodybuilders, which is where misunderstandings begin.
When trying to determine the protein we require, context is extremely important. Spending an hour exercising 4-5 times a week but spending most of the day behind a desk is very different from a professional bodybuilder who exercises twice that amount. Excess protein above and beyond our specific needs will add little value and either be used up as energy, stored as fat or removed from the body
The Indian Council of Medical Research recommends a protein intake of
- 0.8 grams per kg body weight for adults with a sedentary lifestyle (desk jobs, no exercise)
- 1 gram per kg body weight for individuals who exercise moderately. This would essentially apply to individuals with light physical activity
- Over 1 and up to 2 grams per kg bodyweight for very active individuals and athletes.
The American College of Sports Medicine (ACSM) and the Academy of Nutrition and Dietetics have similar recommendations, with 1.2-1.7 g/kg bodyweight for strength athletes and 1.2-1.4 g/kg for endurance athletes.
As per these recommendations, protein intake for a 55 kg woman and a 75 kg man would look like:
|Activity Level||Daily recommended protein intake|
|55 kg Woman||75 kg Man|
|Sedentary||44 grams||60 grams|
|Moderate activity||55 grams||75 grams|
|Intense, regular exercise||90 grams||127 grams|
Our body digests dietary protein breaking it down into amino acids, the building blocks of protein. These amino acids enter our blood stream and are utilized by our body to make various tissues such as muscle fibres, collagen, blood cells, antibodies, hair and nails among others.
There are 22 amino acids that our body needs broadly classified as non-essential, conditionally essential and essential.
- Essential amino acids (EAAs): These are 9 amino acids that our body cannot make and it is essential that we obtain them from the food we eat.
- Conditionally essential amino acids: Our body can generally make these 5 amino acids, but may lose this ability in times of illness, stress or physical trauma. In such conditions, we need to obtain them from our diet.
- Non-essential amino acids: Our body can make these amino acids.
Making sure that the protein we consume provides the essential and conditionally essential amino acids is important, and this is where protein quality comes into play.
The nutritional quality of proteins is measured by a score known as the Protein Digestibility-Corrected Amino Acid (PDCAA) score, which rates proteins based on two factors: the amount of essential amino acids in the protein and how easily our body can digest and absorb it.
Animal protein sources such as meat, eggs and dairy tend to have higher PDCAA scores than vegetarian sources of protein, as they tend to contain higher amounts of the EAAs. With the exception of Soy protein, vegetarian sources are generally low in at least one of the EAAs. Animal protein, however, can be more difficult to digest than plant protein. This generally means that less of the amino acids from the protein can be absorbed by the body. The highest PDCAA scores are generally animal proteins that are easy to digest such as eggs and whey protein.
While plant sources of protein have lower PDCAAs than animal sources, it is incredibly easy for vegans to overcome this by combining plant proteins. For example, legumes such as dal have a low PDCAA score because they are low in the EAA Methionine and rich in the EAA Lysine. Rice, on the other hand, is high in Methionine and low in Lysine. It is no coincidence that cultures across the world have developed combinations like these improve the quality of protein consumed.
However, despite the ease of combining plant protein sources, researchers recommend that vegan athletes and recreational fitness enthusiasts aim to consume protein at the higher end of the recommended range, between 1.4 and 2 grams per kg bodyweight.
Protein in the #PerfectPlate
A quarter, or 25%, of a perfect plate of food would consist of protein. Taking the examples of a 55 kg woman and 75 kg man, with office jobs and 4 days of exercise a week, they would need approximately 66 and 90 grams of protein respectively. Incorporating this into your perfect plate is as easy as filling the 25% with any one of the food choices below, which account for 20 g of protein each. For individuals with a higher protein requirement, it is as simple as increasing the quantity shown in the images.
Making sure that our body has the protein it needs will keep us in the best of health, both physically and mentally. Contrary than the complicated, overly technical approach generally found online, getting the right amount of protein is as simple as:
1.Figuring out how much you need: Multiply your weight in kg by 1-2 to get the amount in grams.
2.Split this amount over the number of meals you have in a day.
3.Pick any of the protein sources mentioned above for each of those meals in the appropriate quantity.
In our next post, we will continue to fill up our perfect plate with the next 25% – grains and starches.