Take a quick look around at any of the current fad diets and you will see just how much importance we place on protein. Keto, Paleo, High Protein, Atkins; it seems everywhere you turn there’s a diet recommending you eat a lot of protein. It’s easy to see why people might be concerned about whether or not they’re getting enough of it in their diets. Are you? is this something you need to worry about? Read to learn about protein requirements, how to figure out if you’re eating enough, and the best protein sources to include in your diet.
Table of Contents
- What is Protein?
- What Are Complete and Incomplete Proteins?
- How Much Protein Do You Need?
- Daily Protein Intake for Older Adults
- What if I’m Looking for Optimal Amounts of Protein?
- Can You get too much protein?
- What Are the Best Vegan Protein Sources?
- Spread Protein Throughout Your Day
- What About Protein Supplements and Powders?
- A Quick Note on Protein As a Percentage of Daily Calories
- Are You Getting Enough Protein?
- That’s a Wrap
What is Protein?
Protein is one of the three macronutrients, along with carbohydrates and fats. Unlike carbs and fat, protein is not usually a major source of energy, but it is a crucial component of every cell in your body. Protein is responsible for the growth of cells and tissues including skin, hair, nails, bones, organs, and muscles. Muscles; that’s what most people think of when they think about protein. Gotta have protein to build strong muscles!
Ask most people where they get their protein from and they’ll likely mention any number of animal products. In fact, tell people you’re vegan and, “Where do you get protein from?” is probably the first question you’ll get. It’s incredible how conditioned we are to think that protein only comes from eating meat, dairy, and eggs. Protein is present in all plant foods; vegetables, whole grains, roots, and even fruit. Your best protein sources, however, are beans, nuts, seeds, and soy products like tempeh and tofu.
Protein is made up of 20 different amino acids, which are broken into two main groups: essential and nonessential amino acids. There are nine essential amino acids, so named because the body cannot produce them itself and so we must get them from food. The other 11 are nonessential because your body is able to synthesize them on its own through normal metabolic processes.
After you eat a meal containing protein, your liver takes the individual amino acids and turns them into proteins that your body can use. Some proteins may get used to make antibodies that will help your immune system fight viruses. Others may help with DNA synthesis or chemical reactions. And some will help repair and build muscles to help you recover from your workouts. Whether you get your protein from an animal or plant, the process of breaking it down into usable amino acids is the same.
In a nutshell, you eat a food that has protein, your digestive system breaks the whole protein into all of its individual amino acids, and then your liver puts the amino acids back together in specific patterns that your body will use to rebuild and repair.
What Are Complete and Incomplete Proteins?
For a long time the theory was that only animal products and soy were “complete” proteins. Complete proteins contained all of the amino acids in sufficient quantities. Plant-based sources of protein were considered incomplete as they were thought to be lacking or low in one or more of the essential amino acids.
Because of this distinction, it was recommended that vegetarians and vegans eat specific combinations of plant products at each meal that “complemented” each other. Complimentary foods contained a higher amount of one or two amino acids that the other food was lacking. The two foods together then made a complete protein, giving your body all of the amino acids it would need. Some popular examples of complementary foods are, rice and broccoli, rice and beans, and pita and hummus.
How did we discover that some foods are incomplete? The idea grew from research completed in 1952 which looked at human requirements for the 8 essential amino acids (we now know there are 9). William Rose and his colleagues looked at the largest amount of amino acids required by any single subject they looked at, and then doubled it! They figured this would “definitely be safe.” (1)
Okay, I like being safe. But if we compare Rose’s calculations with” the amount of each essential amino acid provided by unprocessed complex carbohydrates” we see that “any single one or combination of these plant foods provides amino acid intakes in excess of the recommended requirements” from 1952. (2) I’ll say that again; in excess of amounts that were double the largest amount any subject was observed to need. Furthermore, it was found that mixing foods to make a complementary amino acid composition is unnecessary. (3)
In fact, there is not one documented case of protein deficiency in any individual that is meeting basic human calorie needs!
So, we know that you can get complete proteins from plants, without the need for animal products. But how much protein do we need to eat each day to make sure we have all of the amino acids we need?
How Much Protein Do You Need?
The answer will probably surprise you. it’s likely less than you’ve heard.
If you’ve spent much time in the gym you have likely heard one gram per pound. That’s every fitness trainer’s motto. One gram of protein for every pound of bodyweight. Some will break that down a bit further to one gram of protein for every pound of lean body mass. Lean body mass is how much you weigh without body fat. Just your muscles, skin, bones, and tissues.
One gram per pound is more protein than we need!
The Recommended Daily Allowance (RDA) for protein is set at 0.8 grams per kilogram (2.2 pounds) of body weight each day. The RDA represents the average daily level of intake sufficient to meet the nutrient requirements of nearly all (97 percent to 98 percent) healthy people. (4) This number was not meant to be optimal mind you, just to ensure you aren’t deficient.
Using this recommendation, the average 200-pound person needs about 72 grams of protein each day. That’s a far cry from the 200 grams per day recommendation based on the one gram per pound model!
Not accounting for an individual’s body weight, adult men need about 56 grams a day and adult women need about 46 grams a day. And let me give you a little hint here; if you’re eating enough calories, you are getting at least that much! Meeting the RDA protein requirement is actually very easy.
That covers amounts needed for the average adult man and woman, but because protein is so important for growth and repair, we should look at special times during the life cycle that people may need more.
The following amounts are based on the Revised Reference Values for the Intake of Protein published in 2019 (5):
- Babies need about 10 grams a day.
- School-age kids up to high school need 19-38 grams a day.
- Teenage boys and girls need around 50 grams a day.
- During pregnancy, women need 55 (2nd trimester) to 70 (3rd trimester) grams each day.
- While breastfeeding, women need 71 grams each day.
Daily Protein Intake for Older Adults
Older adults are another population that requires more protein than the general adult population.
Sarcopenia is the progressive loss of “muscle mass, strength, and function” that occurs with aging, and is one of the major threats to living independently as we get older.
There are several reasons for this including a more sedentary lifestyle as people get older. But the primary reasons for age-related muscle loss are due to the fact that elderly adults are less responsive to the anabolic stimulus of protein than younger adults, coupled with the probability of increased insulin resistance in the elderly. (6)
The good news is sarcopenia is both avoidable and reversible! A higher protein intake for elderly populations can combat age-related muscle loss.
Higher protein consumption can overcome this, and help older adults maintain their muscle mass.
How much more do the elderly need? Several studies have shown that an intake “consistent with the upper end of the Acceptable Macronutrient Distribution Range (AMDR) (as much as 30%-35% of total daily calories) may prove to be beneficial.” (7)
Based on this research, an intake of 1.2g/kg should be sufficient for elderly men and women 65 years of age and older. The Mayo Clinic recommends an intake even as high as 1.5 g/kg.
Remember, however, that your body can only use so much protein at any one time. In order to maximize muscle protein synthesis, the best recommendation is to simply try and eat 25 to 30 grams of protein with each meal. (8)
What if I’m Looking for Optimal Amounts of Protein?
So we know that 0.8 grams of protein per kilogram of body weight will keep us from being deficient in protein, but what about optimal intakes?
In 2007, 40 nutrition researchers from around the world gathered at the first-ever Protein Summit. More than 60 reconvened in 2013 to update the protein discussion. Their goal was to look at everything from general metabolic health to weight management, aging, and even maintaining muscle.
Looking at all of the evidence presented at the Summit, a recommendation of up to twice the RDA, so 1.6 grams of protein per kilogram of body weight was determined to be “a safe and good range to aim for.”
This is in keeping with recommendations for the National Council on Strength and Fitness (NCSF), one of the governing bodies through which I held my personal trainer certification. Their recommendations are (9):
- Sedentary lifestyle: 0.8-0.9g/kg of bodyweight (BW)
- Daily physical activity: 1.0-1.2 g/kg of BW
- High-intensity endurance training: 1.3-1.5g/kg of BW
- Bodybuilding or heavy strength training: 1.6-2.0g/kg of BW
Even at the highest recommendation, those for bodybuilders and heavy strength training, the amount required is still less than one gram per pound.
When working with clients who are looking for overall general health, I recommend aiming for 1.2g/kg. That is a safe, research-based intake for optimal health for everyone above the age of 18. If you’re looking for overall general health, find your body weight in kilograms (BW in pounds divided by 2.2) and multiply by 1.2. This will tell you how much you should try and hit each day.
If you are actually counting calories, look back at the end of the day and see how much protein you ate. If you were a bit low, adjust your foods for the next day, but don’t worry much about it. My guess is, if you’re eating a whole-food, plant-based diet including legumes, nuts, seeds, tempeh or tofu, and whole grains, you’re probably getting more than 1.2g/kg.
When I work with athletes, people looking to gain muscle, or those with weight loss goals, I place more emphasis on protein intake. I recommend this population consumes double the RDA, 1.6g/kg. This is quite a high intake of protein, but well within research-based guidelines, and clients have been successful with these amounts.
Can You get too much protein?
Yes, but it’s not likely you will. For normal healthy adults, long-term protein intakes even as high as two grams per kilogram of BW is perfectly safe, with a tolerable upper limit set at 3.5 grams per kilogram of BW. (13) For our 200-pound subject, 3.5g/kg would be a whopping 318 grams of protein a day! That’s the same as eating about 1 pound of meat!
Alright, before you get super excited about eating a ton of protein let’s take a further look.
Protein and carbohydrate each supply four calories for each gram eaten, while fat gives you nine calories per gram. That’s how you go from eating grams of food to total daily calories.
If you are eating a balanced diet (50-60% carbs, 20-25% fat, and 20-25% protein) and you go absolutely nuts eating protein, you can end up eating far too many calories. It doesn’t matter where your calories come from, if you eat more calories than you burn, you will gain weight. In order to eat a lot of protein and keep your calories in check, you would need to drop your carbs and/or fat.
Let’s say you do that.
Our bodies want to use protein as a building block, not as a major source of energy. If you are in an extremely fasted state or eating a very low-carb diet, your body may turn protein into glucose and used it as energy through a process called gluconeogenesis. This is not what your body wants to do, however. We are meant to run on carbs.
And, since your body can’t store excess protein, once your needs are met, the leftover is used for energy or stored as fat. Again, excess calories from any source will be stored as fat.
Balancing your carbohydrates, fats, and proteins and eating the right amount of calories for you is a much healthier option. This will allow your body to use food the way is designed to, and still get enough protein to meet any fitness goal you have.
Now, depending on the form of protein you choose, excessive protein intake can lead to elevated blood lipids (fat in the blood) and heart disease because many high-protein foods are also high in total fat and saturated fat. High protein intake, especially from animal protein, can also be hard on the kidneys.
The kidneys are a very robust organ, but they will be strained by certain medical conditions, including high blood pressure (10) and insulin resistance (11). If you have elevated blood pressure, high cholesterol (12), type 2 diabetes, or a diagnosed kidney concern, you will want to watch and keep your protein intake toward the lower recommended range.
When it comes to protein, more is not necessarily better. Studies have repeatedly shown that more protein, in the 40 grams per meal range, is no more beneficial at one time than 15 to 25 grams. (14) Eat a healthy, balanced diet, with enough calories to fuel your body without adding excess body fat, get enough protein, and you have a recipe for success.
What Are the Best Vegan Protein Sources?
The healthiest protein options are plant sources, such as soy, nuts, seeds, beans, and lentils.
In fact, The Cleveland Clinic polled six dietitians on their top four sources of protein, and the winners were (15):
- Beans and legumes meaning all types of dried beans, split peas and lentils
- wild salmon
- Greek yogurt
Plants for the win, again.
Beans, lentils, split peas, tofu, and tempeh are your major plant-based protein hitters. Not necessarily every one of these every day, but some of them every day. Add in some nuts (walnuts, almonds, pecans, and pistachios), seeds (chia seeds, hemp hearts, and flaxmeal), and nut butters (always opt for all-natural) and you’ve got plenty of options to hit your protein goals and keep your diet exciting.
As an added bonus, walnuts, almonds, chia seeds, hemp hearts, and flaxmeal will provide you with ALA, which converts to all-important omega-3 fatty acids.
Spread Protein Throughout Your Day
Your body can only use so much protein at any one sitting. Your body will use what it can at the time, and then use the rest for energy or store it as fat.
Additionally, eating protein more often will keep protein levels more even throughout the day.
As a general rule, aim to get about 15 grams of protein at each sitting if you are including protein in your snacks. Five meals a day, that would put you in the 75 grams of protein per day category, which is a good spot to be for more adult men and women.
If you typically stick to three meals each day, try and get closer to 25 to 30 grams at breakfast, lunch, and dinner.
What About Protein Supplements and Powders?
I love ’em. Always have. I can’t even think back to a time when I didn’t have a jar of protein in my pantry.
While they aren’t necessary for general health (you’ll get plenty of protein for general health by eating a whole-food, plant-based diet), if you are an athlete, beyond the age of 40, or trying to gain muscle or lose weight, making sure you are aiming for higher amounts of protein, in the 1.2 – 1.6 grams per kilogram of bodyweight category is a good idea. Protein supplements can help you reach those numbers without absolutely stuffing you.
Here are some things to look for in a protein supplement.
- 200 calories or less. We want added protein, not a lot of added calories.
- 2 g or less of saturated fat. This is pretty easy with vegan protein powders.
- No trans fats or partially hydrogenated oils
- 5 g of sugar or less
- I like to look for a protein blend, like plant protein and pea protein from a variety of sources,
- 15 to 20 grams of protein with each scoop.
The best vegan protein powder on the market today is made by Vivo Life. Both their Perform with BCAA and Ritual are amazing. Few ingredients, they blend incredibly well, and they are by far the best-tasting product on the market.
A Quick Note on Protein As a Percentage of Daily Calories
When I talk about protein with individuals, I stick to the numbers I talked about earlier in this article. But I balance this with how many calories the person is eating each day. I never recommend anyone eat more than 25 percent of their daily calories from protein. And I cap that at 3,000 calories a day.
That leaves 75 to 80 percent of your calories to be earned through carbs and fat.
Are You Getting Enough Protein?
Now you know how to check. I’m not asking you to meticulously count your calories every day from here on out to make sure you’re getting enough. But track your food for a week and see where you’re at.
Never tracked calories before? Read Getting Started With MyFitnessPal to learn how to set up a free calorie tracking app, and then give one week a go.
I think you’ll find that you’re getting all you need, but if you’re not, change up your food choices. Add in more tofu, tempeh, and beans to get big protein packages in smaller serving sizes. Or throw in a smoothie using Vivo Ritual as a base protein. After a few days, you’ll have a great idea of how to eat to easily hit your protein needs each day.
Don’t overcomplicate things.
That’s a Wrap
Protein is essential for general health, and you definitely want to make sure you are getting enough. While eating enough calories each day should ensure you are getting enough protein to avoid a deficiency, reaching optimal protein intakes for maintaining muscle, gaining muscle, and losing weight require a bit more purpose. Legumes, nuts, seeds, tofu, tempeh, and whole grains should set the foundation for your protein needs. Protein supplements can be helpful and convenient, but should not be used to take the place of a balanced diet. Eat 15 to 25 grams of protein at each meal, spread throughout the day, and keep reaching toward your fitness goals.
Questions, comments, or concerns? Toss them in the comments below, and keep working hard.