The common mistake people make about eating protein

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You might be trying to eat more protein . You might also be considering the quality of that protein. But have you considered the timing of when you eat it?

Most people are not getting their protein at times of the day that support their body’s optimum use of this nutrient, research suggests.

Shorts

Lots of us eat protein in a skewed pattern through the day, getting almost none at breakfast , a small amount in our lunch, and most of it with our evening meal.

But if protein intake is distributed more evenly through the day, the body can make better use of it, research suggests.

“Most people have very little protein at breakfast,” said Dr Emily Arentson-Lantz, a nutrition researcher at the University of Texas Medical Branch. “If you spread your protein evenly over the day, then you see a better [muscle-building] response.”

Protein goals under debate

Protein is a key part of our diet because it is essential for building and maintaining muscles, as well as many other tissues. Good sources are all kinds of meat and fish, eggs, yoghurt and cheese, as well as beans, peas and pulses.

Just how much protein we need is up for debate. The NHS says we need to eat 0.75g per kg of body weight per day. That translates to about 45g a day for a woman and 55g for a man.

With half a chicken breast containing about 30g, those amounts may not seem out of reach. Indeed, because of the guidelines, it is often claimed people in the UK eat more protein than they really need, and so the current protein craze is misplaced.

But some experts say that target is wrong. It comes from 35-year-old guidelines that worked out how much daily protein people need to avoid becoming acutely ill. The analysis did not work out the optimum amount of protein that would keep people as healthy as possible over the long term.

What’s more, the amount was calculated for someone who is sedentary. Exercise raises your protein requirements.

“This was intended as a minimum maintenance level. But many people want to know what they should do to remain strong, independent and mentally sharp throughout life,” said Dr Chris Macdonald, a behavioural scientist at the University of Cambridge.

Target should double

In the journal, Frontiers in Nutrition this week, Dr Macdonald argued that recent research suggests the daily target for active adults should be about twice the NHS 0.75g/kg figure. This echoes a similar recommendation in 2022 guidelines for athletes from the British Association of Sport and Exercise Sciences.

Assuming we should indeed be aiming for that doubled protein intake, a high-protein breakfast becomes essential for two reasons.

The first is that with the higher target, a typical man would need 120g of protein in a day – and it becomes hard to eat most of that in a single sitting. In a traditional British meal of meat, potatoes and vegetables, for instance, most of the protein would be coming from the meat, and even a whole chicken breast would have only 60g.

Hitting the higher target becomes more realistic if you spread it over, say, three meals with 30g of protein, plus 30g within snacks.

This is especially important for older adults, who are prone to having just cereal or toast for breakfast, said Professor Leigh Breen, a physiologist at the University of Birmingham. “Breakfast and lunch and snacks are great opportunities for people to get up to their required protein intake,” he said.

The second reason for needing a more evenly distributed protein intake is that if we have a large dose of protein in one sitting, the muscles cannot use it all straight away, and so it is thought the surplus is used for energy instead.

How much protein turns to muscle

Exactly how much protein can be turned into muscle from one meal is debated, with figures of 20g to 30g often cited.

The idea was challenged by a study from 2023 , which found that people asked to consume 100g of protein in a shake continued using it to build muscle and other tissues for more than 12 hours afterwards.

And there was more muscle building after the 100g dose than with a comparison 25g dose. “This work highlights that tissues have a much higher capacity to incorporate protein-derived amino acids than previously assumed,” said the researchers.

But perhaps we should not jump to conclusions. The study was carried out on 36 “recreationally active” young men, who had just done an hour of weight training before their protein shake. “Exercise primes our muscle to be much more active,” said Dr Lantz.

“If you are young and healthy and regularly doing resistance exercise, then perhaps yes, you could exceed that 20 to 30 grams of protein at a meal, and your body would still be using it. But if that’s not your lifestyle, maybe we don’t know.”

In other words,…