The protein myth - what do you really need

By Leigh Kirk

I’m sure you’ve either asked this question or maybe even answered it – “how can I get enough protein eating just plants?”

Whole food plant-based eating opens up a world of culinary possibilities for exciting and creative combinations of plant-foods in various dishes both traditional and unique!

So why is this the question du jour when someone finds out you eat a whole food plant-based diet? 

I guess it’s just one of those perception things.  We’ve been taught to associate certain macronutrients with certain foods.  Animals = protein; plants = carbs; oil = fat; etc.

Bar Kayma pasta dishPerhaps we are so used to this simplification that we either forget or may not ever realize that all plant foods contain all of the macronutrients–protein, carbohydrates and fat.  That’s right – my blackberries have protein, carbohydrate and fat in them.  So does my broccoli.  And my rice.  In fact, all of my plant foods—grains, vegetables, fruit, nuts, seeds – have protein, carbohydrate and fat.  Surprised?  I’m betting this realization is a eureka moment for many!



Do you really know how much protein you need?

Well, you might be thinking, surely I’ll need to eat a mountain of broccoli to get enough protein for my daily needs? Broccoli just can’t have enough protein compared to a steak?  Ok then, how much is enough?  Do you really know how much protein you need?  Do you know how the human requirement for protein is calculated?  Or have you been culturally conditioned to the belief that you need a steak to get enough protein?

Nitrogen turnover is the long standing, universally accepted method for determining protein need.  We need to consume 8-10% of our daily calories as protein in order to meet this need (this is the Recommended Daily Allowance or RDA) or 0.8 g/kg body weight/day.  It just so happens that eating ONLY plants provides the necessary amount of protein to meet this need.  In addition, the RDA is calculated to include 2 standard deviations above the average estimated requirement (EAR).  This means that virtually everyone’s need is covered by the RDA and many people will be getting more protein than they need from meeting this recommendation.  In other words, you may even be getting more protein than you need from an exclusively plant-based diet!

Adding animal foods to any great extent quickly catapults us well into excess of our requirement.

Adding animal foods to any great extent quickly catapults us well into excess of our requirement.  Another major health advantage of eating whole plant foods is that we get the recommended amount of daily fiber (14 grams per 1,000 calories according to the Institute of Medicine).  Meat does not contain fiber, and the standard American meat and processed food rich diet typically does not deliver adequate fiber.  Not to mention the health promoting benefits of the world of phytonutrients present in whole plant foods!

Let’s get down to the nuts and bolts.  To calculate your protein requirement, multiply your weight in kilograms by the recommended 0.8 g of protein/kg of body weight/day.  For example, if you weigh 120 lbs, in kg this is 54.43 (divide your weight in pounds by 2.2 to convert to kg).  Now multiply 54.43 kg x 0.8 g/kg/day, and you get a requirement of about 44 g/day of protein.  (See the sidebar for an example of how this requirement is met with a day’s worth of whole food plant-based eating.)

Although the example provided contains tempeh (I particularly enjoy fermented foods), you needn’t fall into a regular ‘tofu trap’!  That’s what I call swapping the daily ‘star of the plate’ from a slab of meat to a slab of tofu or other soy-based food products.  You needn’t ever eat tofu to meet your protein needs, and eating the broadest variety of plant foods is beneficial.  Whole food plant-based eating opens up a world of culinary possibilities for exciting and creative combinations of plant-foods in various dishes both traditional and unique!

While tofu and tempeh made from whole soy beans qualify as a whole food, beware of some of the more processed and refined soy-based ‘fake meat’ products that contain many fractional food ingredients and additive.

Track your own protein intake

If you want to track your protein intake for yourself, record a day’s worth of your whole food plant-based eating, listing all of the foods and the quantities of each consumed.  Then use a nutrient database, such as the USDA National Nutrient Database, to look up the protein content of your foods.  Add the protein content together and compare it to your daily protein requirement which you calculated above.  Voila, you will see that you have met your protein requirement!

If you have other concerns such as adequate iron intake, rest assured that you will obtain adequate iron eating a whole food plant-based diet.  Populations in China eating a whole food plant-based diet were found to have higher iron status than Americans eating a meat-rich diet.  Both meat and plants contain iron; meat contains heme iron and plants contain non-heme iron.  Non-heme iron found in plants is more highly absorbed in the presence of vitamin C (also in plants) than heme iron found in animal foods, which explains why people eating less meat can have higher iron levels.

If you are pregnant, nursing or raising young children, I recommend consulting the Physicians Committee for Responsible Medicine for useful resources on whole food plant-based eating for these stages of life.  []

Do you know how to calculate your own protein requirement?

It is recommended that we get 0.8 g of protein/kg of body weight/day.  Convert your weight from pounds to kilograpms (divide your weight in pounds by 2.2 to convert to kg).  Then multiply your weight in kg by 0.8 g/kg/day to determine your requirement for protein.  For example, a person weighing 120 lbs, weighs 54.43 kg and has a requirement of about 44 g/day of protein.

Check out my plant-based menu to see how easy it is to meet (or exceed!) this need(1):

Breakfast = 14.3g

2 slices flourless, sprouted whole grain toast, 8.0g

1 TB peanut butter, 4.0g

Banana, 1.3 g

½ c fresh blueberries, 1.0g

Lunch= 17.5g

Hummus/Veggies/Salad Wrap, 13.0g

½ c black bean & corn salad, 4.5g

Dinner = 26g

2 c steamed mixed veggies w/tamari, 10.0g

1 c tempeh, 12.0g

½ c brown rice, 4.0g

Total = 57.8 (231.2 kcal)

Based on a 2,000 kcal/day requirement for an active female adult, 57.8 g of protein represents about 11.6% of calories as protein, slightly more than the recommended daily intake of 44 g of protein or 8-10% of calories as protein!

(1) Nutrition values from NutriCalc Plus, McGraw Hill Higher Education.  Accessed from: