What is protein?
Protein is an important macronutrient, essential for normal growth and bodily functions. They are nitrogen-containing substances that are formed by molecules called amino acids, and serve as the major structural component of muscle, bone, skin, and hair. In addition, amino acids are used to produce hormones, enzymes and haemoglobin that carries oxygen around your body. From the 20 amino acids found in protein, 9 of these are ‘essential’ and must be obtained from your diet.
There are many sources of protein available, but not all proteins are the same. It’s important to be conscious of the type, quality, and quantity of protein consumed in your diet daily.
What are the benefits of consuming protein?
Proteins are the building blocks of life, and the benefits go much further beyond building and maintaining lean muscle mass.
Protein is also important for:
- Repairing damaged cells and tissue
- Boosting your immune system, helping to fight infection and inflammation
- Producing enzymes important for many chemical reactions
- Producing hormones such as estrogen, insulin, and thyroid hormone
- Fluid balance in the body
- Regulating pH balance
- Supplying energy, although it is not our main fuel source
- Transporting cells and storing nutrients
- A wide variety of important nutrients for optimal health including: iodine, iron, zinc, vitamins especially B12, and essential fatty acids.
What foods are high in protein?
‘Complete’ protein sources, meaning they contain all 9 essential amino acids that our body needs, include:
- Red and white meat such as chicken, beef, pork, lamb, veal, kangaroo, and turkey
- Fish seafood such as tuna, salmon, white fish, prawns, crab, lobster, mussels, oysters, scallops, and clams
- Milk and milk products like custard, yoghurt and cheese
Plant sources include:
- Legumes and beans, including lentils, chickpeas, red kidney beans
- Raw nuts and seeds
- Tofu and tempeh
Most plant foods are referred to as ‘incomplete’ protein sources, as they do not include all 9 essential amino acids, however they are still high in dietary fibre, antioxidants and phytonutrients.
Protein and Exercise
Protein and exercise go hand in hand – they work together to maintain optimal muscle health. Exercise stimulates the muscles, and protein provides the building blocks for lean muscle mass growth, repair after training, and ultimately, adapting to your training.
How much protein do I need each day?
Daily protein requirements vary, depending on your daily level of physical activity, type of exercise, and your personal health goals.
If you are engaged in intense training, your body will require more daily protein to enhance recovery, ranging from 1.2 to 2 grams per kilogram of body weight. If you are more sedentary, a regular and varied diet is adequate to meet your daily requirements, from 0.8 to 1 gram per kilogram.
Having protein at each meal across the day makes it easier for your body to use protein and optimise the benefits gained from physical activity. Remember to include different protein-rich foods in your main meals and snacks, to ensure your body is getting a variety of essential nutrients for good health.
By Danielle De Francesco
Accredited Practicing Dietitian (BNutrDiet)
Dani De Dietitian