When it comes to our diets, three nutrients reign supreme: Carbohydrates, fats and proteins. These are the macronutrients, and together they’re what give our bodies fuel. Scientists have been speaking up lately about the potential harms of eating too many carbohydrates, and how dietary fats aren’t the enemy we once thought they were. But protein is the crucial third part of the macro trifecta, and focusing on getting enough of it just might be the easiest and most productive thing you can do for your dietary health.
Proteins are made of amino acids, which are the building blocks of our bodies — they make up the cells in our muscles, bones, cartilage, skin, hair and nails. When something breaks, we need protein to repair it. And when our bodies digest food, we need enzymes, which are also proteins, to break food down.
Today, most people aren’t necessarily protein deficient. But research shows that increasing the amount of protein in your diet beyond the current Recommended Daily Allowance (RDA) can have a wide range of health benefits, from weight loss to improved mental health, strength building and more.
Protein – You are Made of It
Eating enough protein is critical to make sure your body has the supplies it needs to stay strong and recover after injuries and illnesses. We’re not talking Schwarzenegger-level musculature, either. Protein builds all bodies of any size.
When you eat protein, it’s broken down into amino acids, which are used to make basic biological components all throughout your body. Our muscles are made of protein, but so are numerous other tissues like our bones and cartilage, skin and even our hair and nails.
Take collagen, for example. Collagen is the most abundant structural protein in the body, and it’s critical for maintaining healthy skin, joints and even blood vessels. Studies have shown that diets rich in collagen lead to improved skin hydration and fewer wrinkles, and can help with joint pain, especially for those with osteoarthritis (de Miranda et al. 2021, Woo et al, 2017).
That’s not to say you shouldn’t pay attention to protein intake when you’re trying to get fit. When you’re exercising, eating enough protein is critical for building new muscles. For example, a study from the Netherlands had two groups of young men do the same exercises, but gave one of them extra protein the night before. Those who got the protein boost ended up stronger by the end of the study than those who didn’t (Snijders et al. 2015).
Researchers have reported that increased protein intake is the best way to add muscle and lose fat when exercising regularly (Antonio et al. 2020). There’s also evidence it can help improve bone density, especially in the lumbar spine which can help with lower back pain (Shams-White et al. 2017).
Protein for Weight Loss
One of the most compelling reasons to eat more protein comes from studies showing the macronutrient can help us lose weight. Cutting pounds carries a range of benefits for anyone who’s overweight, reducing the risk of cardiovascular disease and cancer, and improving everything from the immune system, to sleep, sex drive and more.
(Read more: High-Protein Breakfasts Help Blood Sugar Control)
The simple explanation for the link between protein and weight loss is that protein keeps you feeling full. Unlike carbohydrates, which can lead to a “sugar crash,” protein keeps hunger levels suppressed for longer, meaning it’s far easier to fight the urge to snack. (Fats have much the same effect in the body as well, helping prolong periods between meals.)
In one study, researchers put overweight, middle-aged men on a diet that restricted the amount of calories they ate. Those who ate a high protein diet (25 percent of their calories, compared with 14 percent for the baseline group) were significantly less preoccupied with thoughts of food and were less prone to late-night snacking, the researchers report (Leidy et al. 2011).
In 2016, a team of researchers based at Purdue University reported that across 28 different studies, increased protein consumption was consistently linked to feeling more satiety, the state of lacking hunger (Dhillon et al. 2016). A similar review study from the University of Brasilia looked specifically at people who were overweight or obese and also found that most studies linked protein consumption to improved satiety (de Carvalho et al. 2020).
Protein for Brain Building
If you think eating protein is just for hardcore athletes, think again: More protein in your diet can improve your brain function, too. Remember that proteins are broken down into amino acids, which every part of our bodies use.
One study found that in adults over 60, people who reported eating more protein — especially from meat, eggs and legumes — did better on cognitive tests compared to those who ate less protein or who got their protein mostly from dairy (Li et al. 2020a).
Likewise, increased protein consumption may improve mental health. In a survey of almost 18,000 adults over 18, those who ate more protein in their diets reported fewer depressive symptoms (Li et al. 2020b). Another study points out that lower amounts of dietary protein was associated with poorer cognitive health among people with certain mental health disorders (Dickerson et al. 2020).
But as readers of these pages know, the right dietary fats also play a crucial role here. The fat known as DHA is central to the brain’s signal processing power. So seafood, which offers abundant protein and DHA, is justifiably termed “brain food.”
How Much Protein Should You Eat?
Many studies that report a link between increasing dietary protein and health benefits don’t actually prescribe a specific amount to eat. The current RDA is 0.8 grams of protein, per kilogram of body weight, per day. That’s not much: 54 grams of protein for a 150-pound person, or 73 grams for a 200-pound person. (To appreciate how small these totals are, remember there are about 28 grams in one ounce.)
Researchers from the University of Missouri looked across a wide range of studies and concluded that a healthier target is between 1.2 and 1.6 grams per kilogram per day (Leidy et al. 2015). For a 150-pound person, that’s 82 to 109 grams per day; for a 200-pound person, it’s 109 to 145 grams. They suggest aiming for 25 to 30 grams of protein per meal.
(Read more: The Many Health Benefits of Shrimp)
Is it hard to eat that much protein? Not at all. For comparison, a hard-boiled egg comes with 6 grams of protein, and a half cup of cooked black beans has 8 grams. But to really get protein bang for your buck, turn to lean meats and seafood. A single 6-ounce serving of wild Alaskan silver salmon delivers a whopping 37 grams of protein!
It’s important to remember that not all protein is created equal. Proteins from animals, like meat, dairy and seafood are considered “complete” proteins, meaning they contain all of the essential amino acids our bodies need. Proteins from plants typically don’t contain every amino acid we need, meaning you’ll need to consume multiple sources of protein to get all of the essential amino acids. (And even then, you’ll miss out on nutrients such as vitamin b12, choline and DHA.)
If you’re not sure how much protein you’re already eating, try tracking your food intake for a few days. Many free “calorie counter” apps will sum up daily macronutrient consumption for you, or you can keep a tally manually with some simple arithmetic. Just remember to check the nutrition label to find out how many grams of protein are in a serving of your food — and pay attention to the listed serving size.
And is it possible to eat too much protein? Some have warned that “excessive” protein places a dangerous burden on kidneys, but unless the kidneys are already damaged, that concern does not appear to hold up under scientific scrutiny.
The Bottom Line
Eating more protein leads to a wide range of health benefits because the amino acids they contain are used throughout our bodies. Previous dietary recommendations for protein were likely too low, and researchers now recommend boosting protein consumption for most people.
Some of the healthiest protein sources out there are lean meats, eggs and seafood. Wild Alaskan sockeye salmon (36 grams of protein per serving) is of course a good choice, but you might also try a can of wild skipjack tuna (34 grams of protein), some salmon lox (12 grams) or some wild Pacific spot prawns (17 grams).
And of course, these choices exemplify one of protein’s greatest virtues – they are all delicious!
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de Carvalho, Kênia MB, et al. "Dietary protein and appetite sensations in individuals with overweight and obesity: a systematic review." European Journal of Nutrition (2020): 1-16.
de Miranda, Roseane B., Patrícia Weimer, and Rochele C. Rossi. "Effects of hydrolyzed collagen supplementation on skin aging: a systematic review and meta‐analysis." International Journal of Dermatology (2021).
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Weigle, David S., et al. "A high-protein diet induces sustained reductions in appetite, ad libitum caloric intake, and body weight despite compensatory changes in diurnal plasma leptin and ghrelin concentrations." The American journal of clinical nutrition 82.1 (2005): 41-48.
Woo, T., et al. "Efficacy of oral collagen in joint pain-osteoarthritis and rheumatoid arthritis." Journal of Arthritis 6.2 (2017): 1-4.