High Protein Foods

About protein

Protein is a macronutrient that is essential for our bodies; it is found in the body in muscle, tissues, hair, skin, and bones. Protein is made up of many building blocks called amino acids, which are linked together by peptide bonds.1 There are two different types of amino acids: essential and non-essential.

Essential amino acids cannot be formed in the body and are therefore obtained from the diet; they include the following: 

• Histidine 
• Isoleucine 
• Leucine 
• Lysine
• Methionine
• Phenylalanine 
• Threonine 
• Tryptophan
• Valine 

Non-essential amino acids include amino acids that our bodies can synthesize; they include the following:

• Alanine
• Asparagine 
• Arginine 
• Aspartic acid 
• Cysteine 
• Glutamic acid 
• Glutamine 
• Glycine
• Proline 
• Serine 
• Tyrosine 

Amino acids are used in various metabolic processes and they help to maintain the proper function and structure of the body. They are essential for infant growth, tissue formation,  and milk formation in pregnant and lactating women. 

Creatine is a source of energy for muscle contraction in the body. It is made naturally in the body and consists of three amino acids– glycine, methionine, and arginine. Individuals may also choose to supplement with creatine to improve their athletic performance. 

Protein has a higher thermic effect (20%-30%) when compared to carbohydrates or fats. This means the body works harder to break it down, resulting in greater energy use. It benefits individuals trying to lose weight or gain greater muscle mass through strength training and a higher protein intake.^2,3

Protein has many functions in the body: 

• Appetite regulation
• Weight loss
• Maintaining muscle strength
• Wound healing
• Fight infection
• Repair of old cells
• Generation of new cells
• Hormone formation
• Enzyme formation 
• Transport of DNA and RNA
• Cell membrane formation
• Transport of oxygen 

Foods that are high in protein

Foods that contain all nine essential amino acids are labelled as ‘complete’ proteins and are usually animal products. The majority of plant foods are labeled as ‘incomplete’ as they do not contain all the nine essential amino acids.

Complete protein examples: 

• Meat 
• Fish
• Eggs 
• Dairy products 
• Quinoa

Incomplete protein examples: 

• Soy and tofu
• Beans 
• Pulses 
• Nuts 
• Seeds 

FAQs

What can protein do to our body?

High protein consumption is great for muscle growth and maximizing resistance or strength training adaptations in athletes. In order to benefit from this, it is advised to aim for around 1.6g of protein per kilogram of body weight daily for muscle growth.⁴

Proteins make up the structural components of many enzymes, which allow reactions to happen at a greater rate. Proteins also aid in immunity by recognizing and defending the body against bacteria or viruses.¹

How much protein do we need every day?

Your protein intake is dependent on your weight, age, pregnancy status, and activity levels.

Below is a table of recommended daily intake values of protein to ensure all the needs of the group are being met.⁵

The daily requirements stated above enable you to meet your basic daily protein needs, which represent the minimum amount of protein required to keep you healthy. They may be exceeded depending on your lifestyle. 

Older people may require more protein to avoid risks of sarcopenia, which is a condition that leads to loss of strength and muscle mass in the elderly. Due to reduced mobility and reduced immune function, a high protein intake is essential. The requirements may be as high as 2g/kg body weight for individuals with severe illnesses.^6,7

What will happen if we lack protein in our bodies?

Protein deficiency is quite rare, however, in low economic countries a lack of protein intake can lead to various complications.⁸

• Loss of muscle mass
• Strength reduction 
• Loss of balance 
• Anaemia due to lack of oxygen delivery to the cells 
• Stunt growth in children 
• Increase infections 

For those struggling to gain access to meat and high protein foods, or have a reduced protein intake due to dietary choices (e.g vegetarians) whey protein could be a good alternative as it contains all of the essential amino acids without the requirement of meat consumption.⁹

Is too much protein harmful?

Many foods that are high in protein also tend to be high in total fat and saturated fat, and this has previously been linked to an increased risk of cardiovascular diseases. High protein diets also tend to be quite high in red and processed meats, which have been associated with the risk of health problems such as cancer.¹⁰ It is therefore advised to eat a balanced diet with both plant and animal protein sources. 

Some individuals may exceed their daily caloric intake as a result of trying to consume high levels of protein, which can lead to weight gain. Conversely, due to the higher thermic effect of protein, it may be more beneficial for long-term weight loss when compared to carbohydrates or fats. Additionally, protein provides 4 calories per gram whereas fat provides more than double (9 calories) meaning that a diet higher in protein may be more efficient when the goal is weight loss.¹¹

For those with pre-existing kidney disease, a diet with excessive amounts of protein over time can put a strain on the kidneys, which can eventually result in kidney damage.12 Too much protein consumption can also cause discomfort and indigestion which can lead to exhaustion. It is advised to consume fibe and drink plenty of water to prevent constipation.  

Summary

Proteins are made up of amino acids and are essential for carrying out various functions and processes in the body. Although protein deficiency is quite rare, in developing countries, it can cause health complications and, in some cases, can be life-threatening. 

It is important to note that a higher protein intake can help individuals with muscle growth and repair, especially those undergoing moderate or intensive training. However, that’s not to say that a high protein intake cannot cause weight gain if eaten in a calorie surplus.