Why we need protein

Protein is a critical part of our diet. We need it to feel full, have energy, build and repair muscle, process nutrients and boost immunity, among other vital roles.
“Protein is made up of amino acids that are the building blocks of body tissues, including muscles, blood vessels, hair, skin and nails. It’s also involved in the production of enzymes and hormones that help the body to function normally,” says registered dietitian Kaleigh McMordie.
Why are these amino acids so important? There are some amino acids that the body can synthesise, but others, called essential amino acids, we must get through our diet. Animal protein sources, such as meat, fish, milk and eggs, contain all nine essential amino acids. Most plant-based protein sources don’t have the full complement of amino acids in the exact right amounts (there are some exceptions, like soybeans). “That’s why it is important to include a variety of protein sources in order to get all of the essential amino acids, especially for vegetarians,” McMordie says.
If you’re a regular exerciser, protein is especially important, according to diet and lifestyle dietitian and registered nutritionist Keith Akoob. “Protein not only builds muscle, but it also repairs and maintains muscle,” he says. “Muscle cells, like all living tissue, have a life. They eventually need to be replaced, so repair and maintenance are critical roles for dietary protein.”
How much protein we need

There are many elements to consider when determining just how much protein you need on a daily basis. For example, you need to take into account how often you squeeze in a sweat session and how your body’s digestion is functioning. That said, there are some overall guidelines. “The recommended dietary allowance (RDA) of protein for adult men and women is around 50 to 62 grams per day. This will typically prevent any protein deficiencies,” McMordie says.
Though that’s a rough estimate, Chief Culinary Officer Ken Immer notes, “Most often, we hear about recommending protein in specific gram amounts per day. However, that can be misleading because it should be closely tied to your total calorie needs, rather than just an arbitrary number,” he says. “There is a wide range of recommendations when it comes to the ideal percentage of calories from protein. Ten per cent being the absolute minimum.” Experts aren’t certain of the maximum amount, but too much protein is linked with kidney disease, constipation, and cancer risk.
As a general rule, Immer recommends that men aim for 140 grams and women shoot for 110 grams per day. That’s more than the RDA, but still within safe limits. But if you go overboard, the following are some of the negative effects.
You’re in a bad mood

If you keep waking up on the wrong side of the bed, you might want to consider your protein intake. “When we are eating too much protein, we are often not eating enough carbs, like in low-carb or high-protein diets. And our brains actually run on sugar from those carbs,” Immer says.
The easy solution: recognise when you swap out too many carbs for protein, then even out the difference. There’s no need to wolf down a pizza to brighten your mood. Instead reach for complex carbohydrates such as fruit, yoghurt, brown rice, and whole grain porridge. Limit overly refined carbs, which can make you sluggish and moody. And resist the urge to go carb crazy.