The dark truth about protein shakes: Doctors reveal the deadly health problems they can cause – and why they’re the ‘the biggest con in supplements’

Protein is having a moment as supermarket and health food store shelves groan under the weight of shakes and bars. It is estimated that around one in ten people in the UK eat a protein bar once a week, while a similar number regularly consume protein powders.

And costs don’t seem to be an obstacle. Look at the protein shakes sold at Joe and the Juice, the coffee and juice bar chain. Last year it reported record profits of £45 million, helped by the introduction of protein shakes.

The latest Beets and Berries protein shake (which contains strawberries, beetroot powder, banana, date puree, collagen, whey protein and ‘sproud m*lk’ (a milk alternative made with pea protein and rapeseed and oat oils) costs £9, for example.

Protein is essential for energy, growth, tissue repair and maintenance of our bodies, especially bones and muscles.

Joe and the Juice reported record profits of £45 million last year, helped by the introduction of protein shakes

It supports the function of organs such as the brain, heart and liver. It also plays a crucial role in maintaining aspects of normal body function: for example, our antibodies, an essential part of the immune system, and hemoglobin, which transports blood around the body, are both proteins. Too little protein can affect your immunity and how quickly or well wounds heal.

So should we all – quite literally – join the trend of protein shakes and bars to boost our intake?

The risks (including kidney stones and tooth decay) can outweigh the benefits if you overdo it.

The average adult already consumes more than the recommended amount of protein (45 grams per day for women, 55 grams for men) – women eat 67 grams per day and men 85 grams, according to the government’s National Diet and Nutrition Survey.

And it’s not hard to understand why.

For example, if a woman wants to eat the recommended amount of protein per day, she can have one egg for breakfast (6 grams); 6 oz plain Greek yogurt at lunch (18 g); snack on a handful of nuts (4g); and 2 oz cooked chicken for dinner (14 g) and a milky coffee (3 g).

The demands of athletes and regular gym-goers may be slightly higher because your body needs proteins to repair and grow muscles that are broken down during exercise.

‘It’s about 1.2g to 2g extra per kilogram of body weight per day for endurance training and maintaining muscle mass – and about 1.6g to 2.8g extra per kilogram of body weight per day during periods of strength gains,’ says Dr . Nicolas Berger, a senior lecturer in sport and exercise science at Teesside University. So if you weigh 60kg (9st 4lbs) you will need about 100g more protein to build strength.

And it’s not just regular exercise that increases your protein needs; Just getting older means you need more to maintain your muscle strength.

According to a 2020 study from the University of Sheffield, older people need around 1.2 to 1.5 grams of extra protein per kg of body weight per day. They should consume 25-30 grams of protein with each of their three daily meals.

The demands of athletes and regular gym-goers may be slightly higher because your body needs proteins to repair and grow muscles that are broken down during exercise.

This is to prevent muscle wasting, which in turn can help prevent falls and general frailty, as well as certain diseases such as pressure ulcers, and to speed recovery after surgery. Too little protein can affect wound healing and your ability to fight infections.

The optimal way to get protein, experts say, is from whole food sources, in part because many protein-rich foods are also important sources of other nutrients.

‘It is generally better to obtain protein from natural sources such as beans, legumes, soya, nuts, fish, eggs and meat,’ says Lucy Jones, dietitian and chief clinical officer of Oviva, an NHS weight management provider.

‘These foods provide protein and other essential nutrients, including fiber, vitamins, minerals and beneficial fats.

‘Choosing whole foods for protein intake ensures a more balanced intake of all nutrients, which is often missed when using protein supplements.’

However, another problem with protein bars and shakes is the added ingredients, such as sweeteners and sugars.

“Protein bars and drinks claim to provide an easy way to increase or maintain protein intake, promote muscle recovery, support weight loss or muscle growth – and even claim to be complete meal replacements,” says Dr. Berger.

‘But that’s not always true and they often have very little quality protein [i.e. a type that doesn’t provide all nine essential amino acids needed for muscle production or is in a form that can’t easily be used by our cells] – and many more poor quality added ingredients.’

Common additives of concern, he said, include artificial sweeteners such as sorbitol and mannitol, which can cause bloating and digestive problems.

‘The common thickener carrageenan has been linked to inflammation, while the stabilizers guar gum and xanthan gum can cause digestive problems in sensitive individuals,’ he adds.

‘Such ingredients also make these options ultra-processed foods (UPFs) – foods that have been linked to weight gain and increasingly to conditions such as type 2 diabetes.

‘As such, this could overshadow any health benefits.’

Dr. Nicolas Berger, Senior Lecturer in Sport and Exercise Science at Teesside University

And then there’s the sugar. ‘Many protein bars have sugar added to improve the taste,’ says Raggi Munjal, a dentist from South Yorkshire.

‘So if you eat these bars regularly, say one a day, they can cause tooth decay like any chocolate bar, because of the sugar attack on the teeth.’

They also tend to be high in calories, essentially serving as a snack rather than a proper meal, which can increase unhealthy weight gain. (For example, the Joe and the Juice Beets and Berries protein shake contains 371 calories.)

‘And the irony is that there’s no need to have excess protein, even if you’re sporty,’ adds Jon Dearing, an orthopedic surgeon at Carrick Glen Hospital in Ayr who specializes in sports injuries.

‘Excess protein is simply removed, without being broken down or used by our cells.’

However, having too much protein can overwhelm this process. As Bhaskar Somani, professor of urology at University Hospital Southampton, explains, it can hinder the function of the kidneys and lead to kidney stones: pebble-like pieces of minerals. This happens when there is too much waste in the body and not enough fluid to flush it away, which can then combine with the calcium in the urine to form stones.

‘The stones can block the ureters – the tubes from the kidneys to the bladder – which can lead to infections and, if left untreated and unrecognised, even lead to loss of kidney function and even kidney failure,’ says Professor Somani.

‘I have had quite a few young patients come to me with kidney stones without a history. And when I ask about their lifestyle, I discover that they use protein shakes. The fastest I’ve seen a patient develop a stone after starting it was six weeks!’

Meanwhile, researchers at the University of Pittsburgh found earlier this year that consuming more than a fifth of calories from protein can activate a type of white blood cell that can in turn clog arteries with plaque – a substance that damages blood vessels and restricts blood flow. disrupts. .

Poor blood flow is linked to a higher risk of stroke and heart attacks.

So does anyone really need protein shakes?

Dr. Tom Crisp, consultant in sports and exercise medicine at Queen Mary University of London, is unequivocal. ‘The hype around protein shakes and bars is the biggest negative.

‘Our daily requirement is approximately one steak of 250 grams. Anything more than that is just an expensive way to make you pee more often.”

That’s because excess protein is excreted from the body through urine, causing us to go to the toilet more often.

“For example, if you do competitive weightlifting, you might need a little more, but not much,” he adds.

Dietitian Helen Bond, spokesperson for the British Dietetic Association, agrees.

‘Most people have enough protein in their diet; it is a myth that we need excess amounts. It’s just bandwagoning. Yet we are sold the idea that we have to pay a premium for it.’

Joe and the Juice did not respond to a request for comment.