Often times, meat advocates love to use protein as their trump card when debating the merits of their diets with vegans and vegetarians. They just can’t seem to wrap their heads around the notion that a body can get enough of this crucial macronutrient without regular hamburger consumption.
Honestly, they have a point; eating meat makes it incredibly easy to get all the protein a body needs. That said, the average human body – even the active ones – requires far less protein than the average American eats daily. In fact, there’s scientific evidence showing that low-balling protein intake a little can actually increase longevity (1).
Food is made up of four macronutrients: carbohydrates, fat, water, and protein. Carbs and fat are primarily fuel. Protein can function as a fuel in the human body if need be, but it has several other more important roles, including providing structure, regulating fluids and pH, and building muscle.
When you eat protein, the body breaks it down into amino acids. There are several amino acids in protein, but only nine are essential. The body can’t produce these nine by itself, so they absolutely have to be in your diet.
Here’s where things get a little tricky. Animal products have all nine essential amino acids. However, they don’t have a monopoly on them – or on protein in general, for that matter. Meat, eggs, and dairy tend to be predominantly made up of protein, but many veggies, grains, nuts, and seeds also contain some degree of protein. And if you’re smart about it, it’s not that complex to get the big nine without the benefit of animal sources.
There are a few plant-based sources of all nine, including hemp, spirulina, quinoa and soy. While they should certainly play an important role in any vegans diet, be careful not to overdo them. Relying on one food source can be both problematic and boring. You often end up missing out on vital vitamins, minerals, and phytonutrients. Also, especially in the case of soy, it can bring up health issues. Admittedly, the evils of soy are a little overblown, particularly if you stick to the organic, non-GMO stuff, but moderation is still the smart way to go.
So another great way to get all those amino acids is with the old grain/legume double punch. Legumes (beans, peas, etc.) are strong in half the essential amino acids. Grains (barley, wheat, rice, oats, etc) feature the other half. Eat both and you’ll get all nine. And you don’t need to eat them at the same time. Oatmeal for breakfast and chickpeas on your salad at lunch will have same nutritional impact as having them together.
But as I said before, most plant-based foods have some degree of protein in them, so you don’t need to eat rice and beans 24/7. As long as you keep variety in your diet, you should be okay. Fruit tends to be low in protein, however some foods that are particularly protein-rich include broccoli, cauliflower, kale, mushrooms, romaine lettuce (36% protein by calories. Who knew?), and most nuts.
Now that you know how to get the protein, your next question might be “How much do you need?” Odds are, the answer is “Less than you think.” Grab your calculator and your slide rule and I’ll explain why.
The Recommended Daily Allowance for protein is .8 grams per kilogram of body weight (as opposed to pound of body weight, which is a common mistake). However, for active people, that number goes up a little. According to the International Society of Sports Nutrition, exercising individuals should ingest between 1.4 to 2.0 grams per kilogram per day (2), but we’re talking professional athletes here. If you were a yoga instructor, 1.4 grams would be a good target. The rest of us, however, tend not to put as much demand on our bodies, so let’s look to a 2004 study in the journal Nutrition that recommends 1 gram per kilogram of body weight for people who participate in low to moderate endurance activities (3).
If you’re not math-minded, you can stop here. I assure you that a healthy diet filled with plenty of veggies, legumes, and whole grains will hit those numbers just fine. However, for you left-brain yoginis out there, we’ll walk through the math.
First, let’s figure out your weight in kilograms. Take your weight in pounds and divide it by 2.2. Let’s say that you weigh 140 pounds. That means you also weigh about 64 kilograms.
That also means you need about 64 grams of protein a day. But that’s just a ballpark guess. Keep in mind that every body is different, so it’s up to you to experiment with that and find a number that works for you.
But if you happen to be Joe (or Josephine) Average, take that 64 grams of protein and multiply it by 4 (because there are 4 calories in a gram of protein). That comes to 256 calories of protein per day. You see? Not much – about 13% of your total calories if you’re eating approximately 2000+ calories daily.
To put that in perspective, broccoli is about 33% protein calorically. Kale: 22%. Mushrooms: 26%. Chickpeas: 21%. Kidney beans: 27%. Tofu: 40%. Oats: 17%. Almonds: 13%.
Get the picture?
There’s always a chance that your biology is such that you need to get your amino acids from animal sources, but it’s unlikely. So next time you’re faced with the Great Protein Debate, thank the person you’re speaking with for their concern regarding your well-being. Let them know that you’re aware of the role protein plays in the human body and that you’re getting all you need. If they aren’t swayed, invite them over a big, yummy bowl of rice and beans, Caribbean-style. If logic can’t convince them, maybe their taste buds will.
About Denis Faye:
Formerly "weight challenged," Denis Faye shed 50 pounds following a 5-year jaunt through Australia, a trip that helped him become the extreme fitness and sports enthusiast he is today. He’s been a professional journalist for 20 years, writing for GQ, Men’s Journal, Men's Health, Wired, Surfer, Outside, the Los Angeles Times, the New York Times, Los Angeles Magazine, and Pacific Longboarder. His sports include trekking, rock climbing, mountain biking, spelunking, swimming, scuba, swimming, and—most importantly—surfing. Denis currently writes for Beachbody, which provides effective home workout dvds including the popular P90x program and exercise dvds for the new Insanity: Asylum workout.