The so-called protein revolution has elevated this macronutrient to the forefront of human nutrition. So, what exactly is protein, what foods contain it, and can there be too much of a good thing?
If you’ve been looking at the packaging at your local supermarket lately, you’ve probably noticed the wide variety of protein-packed, high protein, and daily protein intake products available. One recent study bestowed ‘halo status’ on protein health, discovering that it is closely associated with weight management, energy levels, immune health, and overall health. Is the hype, however, justified?
What exactly is protein?
Protein, derived from the Greek photos, which means “first,” is an essential nutrient in our diet. It is essential for muscle growth and repair, as well as enzyme and hormone production. Protein, along with carbohydrates and fat, is one of the three major macronutrients.
Amino acids are the building blocks of proteins, and they’re chemically linked to each other to form various protein combinations. There are 20 different types of amino acids, which are divided into two categories: those that the human body can produce (non-essential amino acids) and those that must be obtained through diet (essential amino acids).”
Why do we require protein?
Protein is found in every cell of the human body and accounts for roughly half of our dry body weight. Protein is broken down in our bodies and helps to maintain muscle mass and metabolism. Protein deficiency can affect almost every aspect of body function, resulting in muscle wasting and a weakened immune system.
How much protein do you actually require?
Protein requirements change with age and vary depending on body weight and gender, According to an expert dietician that protein make up 15-25 per cent of total energy intake. Dietitians in Australia recommend the following protein intake per day for people aged 19 to 70:
- 0.75g per kilogramme of body weight per day for women. For example, if a woman weighs 70kg, her recommended daily intake is 52g.
- 0.84g per kilogramme of body weight per day for men For example, if a man weighs 85kg, his recommended daily intake is around 71g.
- The recommended daily intake for people over the age of 70 is 1g per kg of body weight.
Pregnant women require more protein in their second and third trimesters to ensure the proper development of the baby’s tissues and organs, including the brain. Protein needs to increase to 1g per kilogramme of body weight per day.
What are the best protein sources?
Animal products contain all of the essential amino acids your body requires. This includes red meat, poultry, fish, dairy products, and eggs (egg whites are almost pure protein). Many essential amino acids can also be found in plant-based proteins such as grains, legumes, pulses, and soy products.
For example, Healthline specifies the amount of protein found in the following sources:
- 12 cup raw oats (13g)
- 1 cup of full-fat milk contains
- 8g of protein.1 cup of quinoa contains 8g of protein.
- 28g almonds (approximately 14 cups): 6g protein
- 1 cup chopped broccoli contains 3g of protein.
- 1 egg contains 6g of protein.
- 85g cooked lean beef contains 22g of protein.
- 85g of salmon contains 19g of protein.
It may be easier than you think to meet your daily requirements. For example, if your daily protein requirement is 52g, you’d get even more with milk and oats for breakfast, two eggs for lunch, and fish for dinner.
Do I need to take a protein supplement?
Protein deficiencies are uncommon in Australia, but they can occur in people with special needs, such as those undergoing cancer treatment. People who follow vegetarian or vegan diets must ensure that they eat a variety of plant proteins (see what about plant-based proteins paragraph below) every day. This is to ensure that they receive all of the essential amino acids on a consistent basis.
While protein shakes may appear to be a quick and easy option, getting the same amount of protein from natural foods is just as effective and often less expensive.
Protein shake serving sizes are usually larger than you’ll need in one sitting, given that you’ll be getting protein from other sources in your diet. So you get no extra benefit other than running out of protein powder faster and spending more money on expensive supplements.
A high protein intake may be hazardous, posing risks of decreased heart function, decreased metabolism, mild dehydration, osteoporosis, and bowel disorders.
Protein shakes aren’t always a healthy option; they frequently contain preservatives as well as artificial sweeteners like aspartame and saccharin. If you must have a protein shake on occasion, choose one that is low in sugar and refined grains, preferably made with pea or hemp seed protein powder.
Is it possible to lose weight on a high-protein diet?
If you remember the Scarsdale diet, you remember the 1970s. It was a 14-day high-protein, low-calorie, low-carb weight-loss plan devised by Dr. Herman Tarnower, a cardiologist from Scarsdale, New York. Other high-protein diet weight-loss plans followed, such as Atkins, South Beach, and everything keto.
While many experts considered the Scarsdale diet to be too extreme, if not dangerous, high-protein diets have proven to be an effective weight-loss tool in a variety of situations. Protein lowers levels of the hunger hormone ghrelin while increasing levels of the appetite-reducing hormones GLP-1, peptide YY, and cholecystokinin. In a nutshell, it’s not a miracle: you feel less hungry and thus eat less.
“A high-protein diet is essential for successful weight loss because protein keeps you full while you’re cutting calories,” says Zoe Wilson, an accredited practising dietitian and accredited nutritionist. “However, it’s important to understand that there’s no need to eat massive slabs of meat at every meal.” Protein should account for a quarter to a third of your plate, with vegetables or salad, carbohydrates, and healthy fats rounding out the meal.”
What about proteins derived from plants?
In the meat and dairy aisles, an increasing number of shoppers are opting for plant-based alternatives. Sales of meat substitutes have increased by 60% in the last two years, owing largely to better-tasting products and increased variety. Plant-based meat, dairy, and desserts now have their own ‘alt-protein’ aisle, where soy burgers once languished in a dimly lit corner of the fridge.
Buyers, however, should exercise caution. While plant-based foods are high in nutrients like folate and fibre and lower in saturated fats than meat alternatives, many are low in protein, zinc, and vitamin B12.
Before making significant dietary changes, always consult your doctor.