1 Jul 2019

Are we eating enough protein?

From Nine To Noon, 11:28 am on 1 July 2019

Over the past three decades Australia's national science agency CSIRO has conducted ongoing research into diet and lifestyle.

Part of that research has focussed on protein as part of a balanced diet.

The findings of various studies suggest protein and resistance exercise are the ticket for maintain good health as we age and both contribute to maintaining a healthy weight.

Professor Grant Brinkworth, principal research scientist in clinical nutrition and exercise at CSIRO, told Kathryn Ryan we need to eat more protein than is currently recommended and spread it more evenly across the day.

CSIRO has just released a book, CSIRO Protein Plus, which contains a raft of information, including how you can improve your body composition for better weight management and ways to incorporate protein rich meals across the day, rather than just at dinner.

In the past, guidelines suggested 15 to 18 percent of your total energy should come from protein.

“Now the evidence is we should probably have, to optimize our health, protein intakes of about 1.2 to 1.6 grams per kilogram of our body weight of protein, which translates to 25 percent to 30 percent of your total energy from protein,” Brinkworth says.

Although most of us are probably getting that much protein already, we’re not getting it evenly, he says.

And we don’t get our protein from the right sources, he says.

“We find that too many people get their protein from discretionary foods, which are all those foods that contain the added sugars, salts and the unhealthy fats.”

His message is to eat more protein evenly across the day, and to focus on more core nutrient-dense foods.

Because we tend to load up on the proteins at night, he says.

More evenly distributed protein can help control weight and increase muscle mass, Brinkworth says.

“If we have higher amounts of muscle mass, it means we have a higher resting metabolic rate, which again, which will increase our energy expenditure across the day, which will help us to maintain a low body weight.”

So, what are the best sources of protein?

The advantage of animal protein is they contain all the essential amino acids. Good plant sources include soy and lentils, chickpeas, beans and nuts, he says.

“So you can see that you can easily put together a nice palette of foods across the day using these great protein sources.”

Cutting carbs and upping healthy fats should also be part of the dietary mix, he says, because this can help normalise blood glucose levels.

The good fats are the mono and polyunsaturated fats - derived from foods such as oily fish, olive oil and avocados.

Protein is also vital as we age and naturally start to lose muscle mass – a process called sarcopenia. Evenly distributed protein across the day and resistance exercise are shown to help prevent muscle mass loss, he says.  

Another advantage of eating more good fats and proteins as opposed to carbs is we feel fuller, he says.

“Protein will make people feel fuller, and they'll tend to eat less at the next meal.

“There's another theory called the protein livery hypothesis that suggests humans need sufficient amounts of protein and as soon as we meet those protein needs, we simply stop eating.”

CSIRO Protein Plus, contains information on how you can improve your body composition for better weight management and ways to incorporate protein across the day. It includes recipes - here are three of them: poached egg hash, eggplant parmigiana toasts and chargrilled marinara.