Should you worry about protein deficiency?

Recently, consumer demand for high-protein food has exploded.

Protein powders, candy bars with added protein, protein shakes, protein bagels, protein coffee, and yogurt with extra protein; the list goes on. 

These products will be familiar to anyone who’s ventured into a grocery store over the last few years. But this is a relatively new phenomenon. A few decades ago, no one in the Western world — aside from professional athletes — was worried about protein intake.

Why are companies heavily marketing products with high-protein claims, and do we need this extra protein we're being sold?

First off, let’s ask why we need protein in the first place.

What does protein do in the body?

Protein really is a jack-of-all-trades. It has its fingers in a surprising variety of physiological pies.

For instance, enzymes, which shimmy along chemical reactions in the body, are all protein-based. 

Their jobs include breaking down food in your gut, helping DNA replicate, and destroying toxins in the liver. To say enzymes are important is an understatement, but that’s only one of protein’s functions.

Famously, muscles are mostly protein, as are hair and fingernails. Bones and skin also rely on protein to work and grow.

Other proteins of note:

  • Hemoglobin: The compound that carries oxygen throughout the body.

  • Keratin: A structural protein in skin, nails, hair, and more.

  • Collagen: Another crucial structural protein.

  • Insulin: A hormone that controls blood sugar.

  • Immunoglobulins: Major players in your immune system. 

We could go on, but it’s already clear that you wouldn’t get far without protein in your life.

Proteins are long chains of intricately folded amino acids. In all, about 20 amino acids make all the proteins we need. 

Our bodies can synthesize all of them except nine, which are called “essential” amino acids, and you need to take them in through food. 

How much protein do you need?

The Dietary Guidelines for Americans 2015–2020 recommend that: 

  • Females aged 19 or older need 46 grams (g) of protein daily.

  • Males aged 19 or older need 56 g of protein daily.

The World Health Organization (WHO) recommend 0.83 g of protein per kilogram of weight each day. That works out to around 0.36 g per pound of body weight. 

So, for someone who weighs 150 pounds (lbs), that’s 54 g of protein per day. For someone who weighs 200 lbs, that’s 72 g per day.

As a rough guide, protein should account for roughly 10–35% of your total calories each day.

It’s worth noting that these are just guidelines, though. For example, people training hard for an elite sports event may need to consume more. For most people, however, these levels will be adequate.

But what does this mean in practice? Here are a few food examples:

  • wholegrain rice: 1 portion (75 g uncooked) = 7 g protein

  • walnuts: 1 portion (30 g) = 4 g protein

  • peanuts: 1 portion (30 g) = 8 g protein

  • baked beans: 3 tablespoons = 6 g protein

  • lentils: 3 tablespoons = 9 g protein

  • tofu: 1 portion (100 g) = 8 g protein

  • grilled chicken breast without skin: 100 g = 32 g protein

  • lean grilled beef steak: 100 g = 31 g protein

  • baked fish: 1 serving (140 g) = 25 g protein

  • canned tuna: 100 g = 24.9 g protein

  • cheddar cheese: 1 serving (8 g) = 8 g protein

  • eggs: one medium egg = 7 g protein

  • milk: 1 serving (200 milliliters) = 7 g protein

So, if you were to eat an egg for breakfast (7 g), a cheese salad for lunch (8 g), a grilled chicken breast with whole grain rice for dinner (39 g), and a handful of peanuts as a snack (8 g), you’d have consumed 62 g of protein. 

And that’s without taking into account any milk you might have in your coffee and the plants in your cheese salad, all of which contain at least some protein.

Do we need extra protein?

In industrialized countries, protein deficiency is rare. For example, in the United States, on average, adults eat more than 90 g per day, which is well above the recommended daily amount.

We should note that protein demands change with age. Some older adults, for instance, may consume too little protein. And this can contribute to muscle loss as you age.

Lower protein intake could be for a number of reasons, including changes to older adults' sense of taste and smell. 

Also, a significant proportion of people in long-term care and some people with cancer have protein deficiency. 

Serious athletes first started focusing on their protein intake almost 100 years ago. And research in the 1940s showed that consuming more protein increased muscle mass in power and strength athletes.

At first, these athletes focused on eating more protein in food. It wasn’t until the 1970s and 80s that protein powders hit the shelves. 

Today, it’s not just competitive athletes who choose protein-heavy supplements and snacks.

Anyone who frequents a gym will know that many non-athletes consume jugs of protein-laced fluids before, during, and after a workout. But for these folks, it is unlikely that their protein needs are much different than more sedentary people.

We asked Kate Bermingham, Ph.D., one of ZOE’s nutrition scientists, whether people who visit the gym a few times each week need protein supplements.

She told us, “A food-first approach is ideal — you can consume foods post-workout that also contain other nutrients that help the body recover, such as milk.”

Why is protein so popular again?

The title of a 2013 Wall Street Journal article joked that “When the Box Says 'Protein,' Shoppers Say 'I'll Take It'” — and that seems about right. But why?

There are probably several reasons.

In a social media-savvy world, where every moment can be captured, beautified, shared, and liked, we are becoming increasingly aware of how we look. 

The curves of our bodies can be viewed by millions in an instant. And scientists have linked social media to negative body image.

Perhaps because of this relatively new window into our private lives, people are keen to get an edge when it comes to looking good. So, if a protein supplement might help us look more buff, we’ll take it. 

Added to this, there’s the role of fad diets and food myths, which are deeply embedded in our psyche.

For instance, some sections of the health-conscious community are dead against fats. 

Although the latest research shows that good quality fats are good for your health, scientific findings take time to trickle down. And they can take even longer when the food industry is making money out of the misunderstanding — low-fat foods are big business.

Other sections of the population are vehemently opposed to carbs. The rise of the keto diet is a case in point. But, again, nutrition science shows that carbs, particularly fiber, are important for a healthy gut and beyond.

Regardless of the science, for some people, fats and carbs — two of our three macronutrients — are viewed with suspicion. This means that the only guilt-free macronutrient left is protein. 

Tired of restriction

Another psychological factor might play a part: Fat-free, carb-free, and gluten-free diets have all been popular recently, and they all require cutting something out of your diet. 

The protein craze, however, means adding something in. Finally, we have a dietary change that doesn’t involve restriction!

Additionally, there’s evidence that protein can make you feel fuller for longer. So, in theory, this could help boost weight loss. However, this depends on the type of protein-rich foods you're eating.

As Kate explains, “evidence suggests protein has satiating effects. But a food-first approach is preferable as part of a balanced diet.”

The role of food companies

And here’s where food manufacturers come in. They're always watching and waiting for an opportunity to hawk a new type of product. 

Foods and supplements with added protein have become fashionable. “The food industry follows trends, and, currently, the market is flooded with high-protein products,” says Kate. 

Some of these products are unhealthy — such as chocolate bars — so including high-protein claims can be misleading, and “should not be allowed!” 

Adding protein to existing products is a relatively simple and lucrative idea. So, pushing high-protein ultra-processed foods was a no-brainer.

And if the wrappers of these “sports” bars, juices, and powders show athletes looking pumped, they’ll fly off the shelves.

In the ZOE program, no foods are banned. Our at-home test helps us understand how your body works. This means we can provide tailored nutrition advice. Rather than focusing on restrictions, we can show you the best foods to help you toward your long-term health goals.

What’s the take-home?

If you're an elite athlete, an older adult, or someone in long-term care, you might benefit from upping your protein intake. If you're anyone else, on average, you are likely to be eating enough protein already.

Consuming protein supplements and foods with added protein is unlikely to do you much harm (up to a point), but it’s also unlikely to do you much good.

There is some evidence that increasing protein in your diet might aid weight loss, but most studies focus on protein-dense foods rather than supplements. 

Ultra-processed snacks with extra protein often include added sugar, fat, and sodium, so it’s best to eat these foods sparingly.

At ZOE, we know that a balanced diet with lots of fresh produce is the key to good health. But our research has found that everyone’s body is different.

We’ve shown that everyone has different blood sugar and blood fat responses to food.

Our at-home test measures these responses, and by taking a poop sample, we can analyze your gut bacteria, too. Using all this data, we can provide tailored nutrition advice to suit your body and help you on your path to your health goals. 


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