Protein

Protein is a macronutrient that is composed of amino acids.  There are 20 common amino acids, which make up most proteins.  Protein, along with carbohydrate provides four calories of energy per gram, as opposed to fat which provides 9 calories of energy per gram.

Protein is an essential nutrient for the growth and repair of all the body’s tissues.  Protein can be used as a source of energy for the body, although this only occurs when a person’s dietary intake of the other macronutrients, namely carbohydrate is insufficient.

We get protein from a variety of food groups including animal foods; meat, seafood, fish and poultry, eggs and dairy products; and some plant foods; namely cereals, nuts and legumes. 

Most national nutrition guidelines advise people to consume at least two serves per day of dairy products and at least one serve per day of lean meat, poultry, seafood, eggs, nuts, seeds or legumes. 

It is generally recommended that protein provides between 10-15% of our daily energy intake.  The research from most western countries shows that people typically achieve, and slightly exceed the recommended dietary intake for protein and protein foods. 

In fact high protein diets have become increasingly popular over recent years; however as many of our food sources of protein are also foods that can have a lot of fat in them (especially saturated fat) then a high protein diet can easily become a high fat diet, with the associated risks of excessive weight gain, diabetes, and cardiovascular disease. 

This is why national nutrition guidelines typically recommend;

• choosing low fat protein options such as changing from full fat milk to low fat milk

• trimming and removing visible fat from meat and poultry such as removing the skin from chicken and cutting the visible white fat of steak

• cooking protein foods in low fat ways such as grilling as opposed to frying where fat can drain away from the food as it cooks

While many people have started to embrace the ‘low fat’ lifestyle, the general research shows that we could all do better – full fat milk is still the most common milk consumed by adults in most countries.  So as a personal trainer, encouraging your clients to choose low fat protein options, remove visible fat, and choose healthy cooking methods will help to significantly reduce their caloric intakes through lowering their fat intake.

There is a fair degree of debate within the health and fitness industry regarding protein intakes for active people as opposed to sedentary people.  Athletes and those involved in very heavy physical work will require slightly more protein than the ‘general’ population as there is a greater demand for growth and repair of body tissues. 

Often ‘recreational’ gym goers (typically young men who want to get big muscles as quickly as possible) consume lots of extra protein thinking it will result in ‘more muscle growth, more quickly’. 

There is however no evidence to suggest that eating more protein makes you grow more, or grow quicker, as the body simply tends to use only what it needs at any given time and stores any excess as body fat, and occasionally converts it to glucose for energy. 

So as long as these recreational gym goers (who may well be your personal training clients) have an adequate protein intake they’d be better off consuming more good sources of carbohydrate to fuel their intense training sessions, and incorporate some recovery sessions so they’re not bench pressing every day of the week!

Interestingly there is also no evidence to support the idea that growing children need more protein than others, as long as they are consuming the recommended serves per day of protein foods.  Again addressing the sources of carbohydrate intake would be more appropriate for young children to ensure they are consuming foods that provide a sustained release of energy to meet their daily energy demands.

Now what if our intake of protein is deficient?  As protein is responsible for growth and repair of all body tissues then a shortage can cause problems with recovery from training (i.e. the body’s ability to repair the damage caused by training may be impaired).  As proteins are also vital for the synthesis (manufacture) of many hormones, antibodies and enzymes then people with diets deficient in protein may have problems with energy production and digestion amongst other things. 

Such problems are generally rare and reserved only for some vegetarians or vegans if they don’t quite have their plant protein intakes balanced.  Vegetarian diets are generally adequate in protein because the proteins of dairy products, eggs, legumes, nuts, breads and cereals are rich in essential amino acids.  Plant-based diets generally include legumes, nuts and seeds, low-fat milk and/or soy products and eggs.  A combination of different plant foods each day should ensure sufficient protein in a vegetarian diet.