It’s not a style of eating that most of us talk about anymore: the high-protein diet. Instead, the focus is usually on fats (such as with the keto diet), a particular region (aka the Mediterranean diet) or even a heavily branded one (like the Atkins Diet, South Beach Diet or Dukan Diet).
But this one macronutrient — protein — plays a key role in most diets and eating plans (see the many benefits of a high-protein diet below). Moreover, high-protein foods provide nutrients that are used by every part of the body to develop, grow and function properly.
Because proteins are involved in just about every body function, it’s important that you consume foods high in protein every day, ideally with every meal.
While most people don’t suffer from a protein deficiency, they are more likely to not eating enough protein in their daily diet and can be vulnerable to not getting enough protein nutrition for muscle repair or proper satiety, for example. On a high-protein diet, you are likely to feel more satisfied after eating, and you’re less likely to get the blood sugar highs and lows that lead to cravings and moodiness.
What Is a High-Protein Diet?
A high-protein diet is an eating plan in which at least 20 percent or more of your total daily calories comes from protein. Most high-protein diets aim higher, such as 30 percent of total calories. Most high-protein diets restrict the intake of carbohydrates, so they can go hand-in-hand with low-carb diets but not always.
Getting to such a protein intake goal is easier said than done, as anyone going on a high-protein can report. It requires planning and focus. It also relies on high-protein foods, naturally, such as meats, seafood, dairy, eggs and beans.
Not only are these foods high in protein, but they’re also high in nutrients. One of the first benefits that a high-protein dieter will experience is a reduced appetite, as protein foods are very filling.
What does protein do to your body? Here are some of the top benefits of a high-protein diet:
1. Boosts Muscle Mass
Including plenty of foods high in protein in your diet is necessary to build and maintain healthy muscle mass, while also supporting tendon, ligaments and other body tissue. While high-protein foods are important for bodybuilding, they are also necessary for developing leaner muscles.
When your diet is lacking in amino acids, “muscle wasting” (or muscle atrophy) can take place when your muscle fibers are broken down to support your body’s energy needs.
High-protein foods are especially important after exercise, since physical activity like strength training purposefully damages muscle tissues so they can repair and grow back stronger. For the process to happen effectively, you need some extra protein to help repair the damage.
While protein alone won’t enhance athletic performance, research shows that eating protein benefits performance when eaten before and after exercise. It helps increase muscle recovery, promotes muscle synthesis and serves as effective muscle ache treatment.
2. Helps Manage Your Weight by Filling You Up
Although some research studies show conflicting results regarding high-protein diets versus low-protein diets for maintaining an ideal weight or losing weight fast, there’s plenty evidence that protein helps make you feel full and can prevent overeating.
Studies show that controlled calorie intake in association with a moderately high protein intake can be an effective and practical weight-loss strategy.
Some of the reasons this is true? Protein functions to increase satiety to a greater extent than carbohydrates or fats, helping prevent overeating and snacking.
It’s usually much easier to overeat carbohydrates, especially if they’re refined or sweetened, than it is to overeat healthy protein foods.
Eating protein also creates a process in the body known as thermogenesis, which requires the body to expend more energy (calories) in order to digest food. At the same time, protein helps ward off muscle loss that can result from a low-calorie diet, which makes certain protein foods beneficial for weight loss.
3. Stabilizes Blood Sugar Levels
Insulin is a hormone that’s required for carbohydrates, fat and protein to be metabolized. However, carbohydrates require much more insulin than fat or protein.
The major determinate of blood sugar levels is the glycemic index response from the foods you eat, so while eating high-carb and high-sugar foods results in fluctuations in blood sugar levels, eating high-protein foods does the opposite.
Eating foods with protein has a minimal effect on blood glucose levels and can, in fact, slow down the absorption of sugar during a meal. This means a low-carb, high-protein diet can help prevent spikes in blood glucose, which is especially important for preventing type 2 diabetes, balancing energy levels, and keeping your appetite and mood in check.
4. Improves Your Mood
Certain amino acids from high-protein foods are needed to balance hormones naturally, control your mood and act as a natural treatment for anxiety. According to studies, proteins help neurotransmitters function and synthesize hormones like dopamine and serotonin that calm us and keep our outlook positive.
Many people who are lacking in key amino acids start experiencing weakness, moodiness, and increased anxiety or signs of depression for this reason. Because protein helps stabilize glucose in your blood, it also prevents mood changes, irritability and cravings that can occur due to fluctuating blood sugar levels.
5. Promotes Healthy Brain Function and Learning
Proteins are needed to make enzymes, hormones and neurotransmitters that are critical for cognitive function. As your mother may have told you when you were a kid, eating a healthy breakfast sets the tone for the day and prepares you to learn and remember information.
The brain requires a steady supply of amino acids in order to keep concentration, focus and energy levels up. Studies show that when amino acid deprivation takes place, learning and coordination suffers, but once all necessary amino acids are reintroduced into the diet, learning and motor skills improve.
6. Helps Maintain Strong Bones
Many studies now show that a positive association exists between eating more foods with protein and better bone health. The effects of protein on bones also relate to the specific high-protein foods eaten and intake of important bone-building nutrients like calcium and magnesium.
A diet high in protein from whole, nutrient-rich foods can help heal broken bones and prevent bone weakness, fractures and even osteoporosis by increasing calcium absorption and helping with bone metabolism.
Recent studies on the elderly in the U.S. show that the greatest bone losses occur in people with low protein intake of 16–50 grams per day. It’s believed that when someone eats a low level of protein, insulin-like growth factor production is reduced, which in turn has a negative effect on calcium and phosphate metabolism in the bones and bone formation.
7. Protects Heart Health
Some studies show that an inverse relationship between protein intake and risk of heart disease has been observed in adults, as higher protein diets appear to be one of the natural remedies for high blood pressure. Also, substituting carbohydrate foods with protein results in lower LDL “bad” cholesterol and triglyceride levels.
One reason this might be true is because higher protein diets balance blood sugar and tend to help prevent other heart disease-related causes, including obesity and diabetes.
8. Slows Aging and Promotes Longevity
One of the key roles of high-protein foods is helping the body synthesize glutathione, often called the “master antioxidant.” Glutathione is stored within our own cells and helps us detox and reduce carcinogens that age us.
Animal and human studies both show that adequate protein intake is crucial for the maintenance of glutathione and helps the body stay in a state of balanced “homeostasis.”
Glutathione deficiency contributes to oxidative stress, which plays a key role in age-related diseases like Alzheimer’s disease, Parkinson’s disease, liver disease, cystic fibrosis, sickle cell anemia, cancer and viral infections.
Research shows that diets that include enough foods that are high in protein can help treat muscle loss due to aging (called sarcopenia). A diet that has adequate levels of protein helps slow the aging process by keeping muscle mass intact, supporting strong bones, and maintaining high cognitive and immune function.
In the elderly, amino acid deficiencies can potentially lead to eye problems like cataracts, heart problems, muscle loss, weakness and mood changes.
As you age, your body is less capable of synthesizing amino acids on its own, which is one reason why the amount of muscle you have tends to decrease over the years while fat accumulates. This makes it even more important for you to eat plenty of protein-rich foods to support not only a healthy body weight, but to keep your memory sharp, energy up, and strength and balance in place.
Protein for Vegans/Vegetarians
You don’t have to eat meat or animal products to follow a high-protein diet. There are actually plenty of plant foods high in protein, such as nuts and seeds.
For those of you on a vegetarian or vegan diet, focus on these vegan high-protein foods to increase your consumption:
- beans (black beans, lima beans, pinto beans, chickpeas)
- nuts (almonds, peanuts, pistachios, cashews)
- nut butter (almond butter, cashew butter, sunflower seed butter)
- brown rice
- seeds (chia seeds, flaxseeds, pumpkin seeds, hemp seeds)
- leafy greens (spinach, kale)
How Much Protein Per Day?
We all need a different level of protein based on our exact needs. For example, your body weight, gender, age, and level of activity or exercise all determine how much protein is best for you.
Before determining your macronutrient needs and how many grams of protein per day, it’s important to figure out how many calories you should aim for each day. To do this, you should start by calculating your basal metabolic rate, which is the number of calories that your body needs to function, not including physical activity or exercise.
There are plenty of online calculators available that you can use to figure out your caloric needs. Use our calorie calculator.
There are also some health conditions that require people to either eat more or less protein-rich foods than the average person. And athletes need to eat even more foods for energy and performance, including plenty of quality protein.
That said, there are some general protein guidelines that can serve as a good recommendation to aim for each day. According to the U.S. Department of Agriculture, the recommended daily intake of protein for adults who are at an average weight and activity level is:
- 56 grams per day for men
- 46 grams per day for women
In my opinion, the amounts above are the minimum protein intake you should aim for each day, assuming you are otherwise healthy and are moderately active.
More ideally, I advise that you try to make protein at least 20 to 30 percent of your calories per day. That equates to about 0.6–0.75 grams of protein per pound of body weight, or 1.2–1.6 grams per kilogram.
You can start by making about 30 percent of your plate a high-quality source of protein at every meal. This ensures you eat enough throughout the day to meet your needs and prevents you from overeating carbs and junk foods.
It’s best to eat small amounts of protein throughout the day instead of a very large serving only once or twice. This gives your body the right amount of protein it needs at any given time, since only so much can be utilized at once. (The rest is stored as fat or eliminated.)
Because your body cannot store protein, eating it throughout the day is the surest way to balance your blood sugar levels, ward off hunger and support your metabolism. This is especially important around the time of exercise when protein-rich pre-workout snacks can go a long way.
High-Protein Diet Guidelines
If you seek to follow a high-protein diet, the general rule that I like to follow for consuming protein is eating around 30 percent of your body weight in grams of protein per day. That means about 0.75 grams of protein per pound of body weight, or 1.6 grams per kilogram. So if you weigh 160 pounds, you should be consuming about 120 grams per day.
In fact, studies indicate that diets that average around 0.75 grams of protein per pound, or 1.6 grams per kilogram, can increase weight as well as fat loss, improve body composition and even preserve muscle during the weight loss period.
An easy way to wrap your head around consuming enough protein in one day is to divide the amount of grams you want to eat by the number of meals you consume. If you eat three meals every day and an afternoon snack and want to consume 120 grams of protein, then that’s about 30 grams of protein per meal/snack.
Now break that down even further — 25 grams of protein is about a three-ounce serving (about the size of a deck of cards) of grass-fed beef, organic chicken or wild-caught salmon. Combine your meat with a serving of beans and you have plenty of protein sources in your meal already. Equally, most protein powders average around 20 grams of protein per serving, and a protein shake makes for a great snack or breakfast.
Even leafy greens or vegetables like broccoli and Brussels sprouts contain some protein, so adding these vegetables and raw cheese to an omelet is another great way to consume over 30 grams of protein per meal.
To address your mid-day hunger and hit your protein intake goals, there are plenty of high-protein snacks that you can turn to. Examples of protein-rich snacks include black bean hummus, yogurt bites, deviled eggs and even cashew butter chocolate chip cookies.
Risks and Side Effects
Some people are concerned that kidney or liver function can suffer when their diets are too high in protein. However, there isn’t much evidence that a well-rounded diet that has moderate to high levels of high-quality protein will cause problems in otherwise healthy people.
Similarly, as mentioned earlier, protein seems to help with bone and heart health.
That said, eating very high levels of protein is correlated with some health risks in certain instances.
What happens when you eat too much protein? Eating more calories in general than your body can use, whether from sources of protein or another source, will not result in better health and will contribute to weight gain.
Very high protein might also lead to digestive problems like constipation, changes in blood sugar levels, and possibly bacteria and yeast growth in the gut.
Neglecting other nutrients and eating a large sum of protein can also put stress on your organs while they work to balance your body’s pH level (since animal foods can be acidic in nature) — plus proteins make your body remove more nitrogen waste products from your blood.
Of course, eating a well-rounded diet that’s varied in terms of foods is important for optimal health. Just like you wouldn’t want to consume large amounts of sodium, you’ll find do not want to overcome any food, even high-protein foods.
To sum it up, protein plays a big part in a healthy diet, but quality is key — plus you don’t want to simply load up on high-protein foods all day long without eating enough vegetables, fruit and healthy fats.