November 19, 2012 9.46 am This story is over 144 months old

Your health: The facts about protein

Practical protein: Local nutritionist Rachel Linstead explains the importance of protein in a healthy diet, and where it comes from.

Incorporating protein into your diet is very important, especially so if you are vegetarian or vegan. The body uses protein for essential processes such as growth, repair, muscle contraction and aiding immunity. Protein provides structural support in skin and bone. Occasionally, your body uses protein for energy, but this only happens when there is an excess of dietary protein/an inadequate supply of dietary carbohydrate and fat.

Amino acids are the building blocks of protein. Twenty amino acids are needed to build the various proteins used in the growth, repair and maintenance of body tissues. Eleven of these amino acids can be made by the body itself (the non-essential amino acids), while the other nine (essential amino acids) must come from our diet, but all 20 amino acids are necessary for health.

Different protein sources are:
Animal:

  • Meat
  • Fish
  • Poultry
  • Game
  • Dairy products (milk, yoghurt, cheese)
  • Eggs

Vegetable:

  • Soy protein (tofu, soy milk, soy mince, tempeh (fermented soybeans), miso (fermented soybean paste)
  • Pulses (peas, beans and lentils)
  • Quorn (mycoprotein made from fungus)
  • Quinoa – pronounced ‘keenwa’ (known as the mother-grain from South America)
  • Nuts and seeds
  • Avocado

However, not all protein is equal. You may have heard of the term “good quality protein” – this refers to whether the protein contains all nine essential amino acids. Though it’s not as simple as that. It’s important to consider the other constituents of the protein.

All animal proteins contain the nine essential amino acids, however some animal protein is high in saturated fat, whereas some vegetable proteins don’t have all the amino acids, but are high in other nutrients like fibre, vitamins and minerals and are naturally low in fat. Most vegetable protein doesn’t contain all the essential amino acids, so vegetarians and especially vegans must get their protein from a variety of sources.

One way to ensure that you are consuming the full range of amino acids is by protein combining. This means eating two or more foods which complement each other in their amino acid levels.

  • Beans on toast
  • Cheese or peanut butter sandwich
  • Rice with beans or peas.

When eating meals or snacks, incorporate protein because this slows the digestion of carbohydrates helping you to feel fuller for longer.

How much protein should I eat?
The UK Department of Health recommends that women have an average of 36g of protein a day and men have 44g. This average though will depend on your life stage, such as pregnant women, very active people or heavy manual workers.

Rachel Linstead is a nutrition consultant at Firecracker, a nutritional therapy and consultancy service for businesses and individuals.