Protein is having a moment, with supermarket and health food store shelves groaning 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 consume protein powders regularly.
And the cost does not seem to be an impediment. Check out the protein shakes sold at Joe and the Juice, the coffee and juice bar chain. Last year it posted a record profit of £45m, helped by the introduction of protein shakes.
Your ultimate beet and berry protein shake (containing strawberries, beet powder, banana, date puree, collagen, whey protein and ‘sproud m*lk’ (a milk alternative made with pea protein and pea oils). rapeseed and oats) costs £9, per instance.
Protein is vital for energy, growth, tissue repair and maintenance of our body, especially bones and muscles.
Joe and the Juice reported a record £45m in profits last year, helped by the introduction of protein shakes.
Supports the function of organs such as the brain, heart and liver. It also plays a vital role in maintaining aspects of the body’s normal functioning: for example, our antibodies, an essential part of the immune system, and hemoglobin, which transports blood throughout the body, are proteins. Too little protein could affect your immunity and the speed or quality of wounds.
So should we all embrace (literally) the trend of protein shakes and bars to increase our intake?
The risks (including kidney stones and cavities) can outweigh the benefits if you overdo it.
The average adult already consumes higher than recommended levels of protein (45 g per day for women, 55 g for men): women eat 67 g per day and men 85 g, according to the National Diet and Nutrition Survey of the government.
And it’s not hard to see why.
For a woman, for example, to eat the recommended amount of protein in a day, she could have one egg (6g) for breakfast; 6 ounces of plain Greek yogurt at lunch time (18 g); eat a handful of walnuts (4 g); and 2oz of cooked chicken for dinner (14g) and a latte (3g).
The requirements of athletes and regular gym goers may be slightly higher, as their body needs protein to repair and build muscles that are broken down during exercise.
“This is about an additional 1.2 to 2 g per kilogram of body weight per day for resistance training and maintaining muscle mass, and about an additional 1.6 to 2.8 g per kilogram of body weight per day. day during periods of strength gain,” says Dr. Nicolas Berger. Senior Lecturer in Sport and Exercise Science at Teesside University. So if you weigh 60 kg (9.4 pounds), you’ll need about 100 g more protein to build strength.
And it’s not just regular exercise that means your protein needs increase, but getting older means you need more to maintain muscle strength.
Older people need an extra 1.2 to 1.5g of protein per kg of body weight per day, according to a 2020 study by the University of Sheffield. They should consume between 25 and 30 g of protein in each of their three daily meals.
The requirements of athletes and regular gym goers may be slightly higher, as their body needs protein to repair and grow muscle that is broken down during exercise.
This is to prevent muscle wasting, which in turn can help prevent falls and general weakness, as well as certain illnesses such as pressure ulcers, and to speed recovery from surgery; Too little protein can affect wound healing and your ability to fight infection.
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.
“In general, it is best to get protein from natural sources such as beans, legumes, soya, nuts, fish, eggs and meat,” says Lucy Jones, dietitian and clinical director at NHS weight management provider Oviva.
«These foods provide protein and other essential nutrients, such as fiber, vitamins, minerals and beneficial fats.
“Opting for whole foods for your protein intake ensures a more balanced intake of all nutrients, something that is often overlooked when using protein supplements.”
However, another concern regarding protein bars and shakes is their added ingredients, such as sweeteners and sugars.
“Protein bars and drinks claim to be a convenient way to increase or maintain protein intake, aid muscle recovery, support muscle weight loss or gain, and even claim to be complete meal replacements,” says Dr. Berger.
“But this is not always true and they often have very little quality protein (that is, a type that does not provide the nine essential amino acids necessary for muscle production or is in a form that our cells cannot easily use) – as well as many other poor quality added ingredients.’
Common additives of concern, he says, include artificial sweeteners like sorbitol and mannitol, which can cause bloating and digestive upset.
“The common thickener carrageenan is linked to inflammation, while the stabilizers guar gum and xanthan gum can cause digestive discomfort in sensitive people,” he adds.
‘These ingredients also make these options ultra-processed foods (UPFs), foods that have been linked to weight gain and, increasingly, diseases 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 sugar. “Many protein bars have added sugar to improve their taste,” says Raggi Munjal, a dentist in South Yorkshire.
“So if you eat these bars regularly, one a day, for example, they can cause cavities like any chocolate bar would, due to the attack of the sugar on the teeth.”
They are also often high in calories for what is essentially a snack rather than a proper meal, which can increase unhealthy weight gain. (Joe and the Juice Beets and Berries protein shake contains 371 calories, for example.)
“And the irony is that you don’t need to have excess protein, even if you are an athlete,” adds Jon Dearing, an orthopedic surgeon at Carrick Glen Hospital in Ayr, who specializes in sports injuries.
“Excess protein will simply be removed without being broken down or used by our cells.”
However, consuming too much protein can overwhelm this process. As Bhaskar Somani, professor of urology at Southampton University Hospital, explains, it can hinder kidney function and lead to kidney stones – pebble-shaped pieces of minerals. This happens when there is too much waste in the body and too little fluid to remove it, which can then combine with calcium in the urine to form stones.
“Stones can block the ureters (the tubes that run from the kidneys to the bladder), causing infections and, if untreated and undetected, can 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 with no previous history. And when I ask them about their lifestyle, I find out that they drink protein shakes. The quickest I’ve seen a patient develop a stone after starting them is six weeks!’
Meanwhile, earlier this year, researchers at the University of Pittsburgh found that consuming more than a fifth of your calories from protein can activate a type of white blood cell that can in turn clog arteries with plaque, a substance that It damages vessels and disrupts blood flow. .
Poor blood flow is linked to an increased risk of strokes and heart attacks.
So does anyone really need protein shakes?
Dr Tom Crisp, a consultant in sports and exercise medicine at Queen Mary University of London, is unequivocal. ‘The hype surrounding protein bars and shakes is the biggest downside.
‘Our daily needs amount to approximately one 8-ounce steak. Anything more than that is just an expensive way to make you pee more often.”
This is because excess protein is excreted from the body through urine, causing us to go to the bathroom more.
“If you do, for example, competitive weightlifting, you may 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 excessive amounts. It is simply a collective movement. However, they are selling us the idea that we should pay a premium for it.’
Joe and the Juice did not respond to a request for comment.