If you are a long term vegan, or someone who has done their ‘nutrition homework’ throughout their transition into veganism, you will most definitely read a few articles about the protein deficiency myth.
Most vegans are aware that if they follow a varied whole-food vegan diet, consisting of a good amount of pulses, nuts, and greens, combined with a sufficient calorie intake, protein deficiency is something they do not need to worry about. Still, I have decided to post a more detailed analysis into the subject and take into consideration a few factors that may vary from person to person. Again, I will stress that too many vegans are trying to prove a point of ‘no supplements needed’ without taking into consideration the fact that each body is different and there is no ‘one size fits all’ answer for a question concerning each individual’s body and health.
Clarifying Protein Needs
In summary, although protein is a key nutrient, responsible for ‘building’ our organs, including skin, hair, nails, and muscles, we don’t need huge amounts of it. The RDA recommends that we take in 0.8 grams of protein for every kilogram that we weigh (or about 0.36 grams of protein per pound that we weigh) (1). This recommendation includes a generous safety factor for most people. When we make a few adjustments to account for some plant proteins being digested somewhat differently from animal proteins and for the amino acid mix in some plant proteins, we arrive at a level of 0.9 gram of protein per kilogram body weight (0.41 grams per pound). If we do a few calculations we see that
The protein recommendation for vegans amounts to
close to 10% of calories coming from protein. For example, a vegan male weighing 174 pounds could have a calorie requirement of 2,600 calories. His protein needs are calculated as 174 pounds x 0.41 g/pound = 71 grams of protein. 71 grams of protein x 4 calories/gram of protein = 284 calories from protein. 284 divided by 2,600 calories = 10.9% of calories from protein.
If we look at what vegans are eating, we find that, typically, between 10-12% of calories come from protein 3. This contrasts with the protein intake of non-vegans, which is close to 14-18% of calories.
So, in the United States it appears that vegan diets are commonly lower in protein than standard American diets. Remember, though, with protein, more (than the RDA) is not necessarily better. There do not appear to be health advantages to consuming a high protein diet. Diets that are high in protein may even increase the risk of osteoporosis (4) and kidney disease (5). Overconsumption of protein may cause problems for your hear.t It may also promote the growth of cancer cells, cause digestive problems, and harmful mineral imbalances.
Sample Menu Showing How Easy It Is To Meet Protein Needs
1 cup Oatmeal
1 cup Soy Milk
1 medium Bagel
2 slices Whole Wheat Bread
1 cup Baked Beans
5 oz firm Tofu
1 cup cooked Broccoli
1 cup cooked Brown Rice
2 Tbsp Almonds
2 Tbsp Peanut Butter
Protein Recommendation for Male Vegan
[based on 0.9 gram of protein per kilogram body weight for 70 kilogram (154 pound) male]
Even the original advocate of combining proteins, Frances Moore Lappé, author of Diet for Small Planet, eventually recanted her theory and concluded that acquiring protein from a plant-based diet was “much easier” than she had thought. Vegans eating varied diets containing vegetables, beans, grains, nuts, and seeds rarely have any difficulty getting enough protein as long as their diet contains enough energy (calories) to maintain weight.
We actually have a biological requirement for amino acids, not for protein. Humans cannot make nine of the twenty common amino acids, so these amino acids are considered to be essential. In other words, we must get these amino acids from our diets. We need all nine of these amino acids for our body to make protein.
Amounts of Foods Providing Recommended Amounts of Essential Amino Acids
12-3/4 cups of cooked corn OR 8 large potatoes OR 2-1/2 cups of tofu OR 15-1/2 cups of cooked brown rice
Any one of the above foods, eaten in the amount specified, would provide the recommended amounts of all essential amino acids for an adult male. Women would need about 20% less of each food due to lower recommendations. This concept is illustrated below:
Adult RDA,154 lb male (1)
12-3/4 cups corn
8 large potatoes
2-1/2 cups tofu
15-1/2 cups cooked rice
Source: USDA Nutrient Database for Standard Reference, Release 24, 2011.
Notes: Amounts of amino acids are in milligrams. Try=tryptophan, Thr=threonine, Iso=isoleucine, Leu=leucine, Lys=lysine, Met+Cys=methionine+cysteine, Phe+Tyr=phenylalanine+tyrosine, Val=valine
Before looking deeper into this point, I would like to stress the following – this information is valid for vegans and non-vegans alike! A vegan diet is not necessarily responsible for the following phenomenon! This is just an important piece of information everyone should be aware of.
I started looking into this topic, because I have always considered myself as a healthy eating individual. I eat huge amounts of nuts, fruits, veggies, and all the good stuff we are supposed to. I have also limited my intake of refined sugar and gluten over the last few years. My blood tests are perfect, and I don’t have any deficiencies. Yet, after making close observations to my body, I discovered that with the amount of physical activity I do, I cannot make it without a protein powder supplement. This is despite the fact that I am clearly getting enough calories and protein from my food alone! I spent a few months without a supplement, and I was feeling chronically fatigued, unable to complete my workouts and my physical strength plummeted quite visibly. On the contrary, within a few days of taking a high quality protein supplement, my physical condition changed quite noticeably.
This led me to the idea that our bodies absorb nutrients in different ways
Before I present some scientific facts on this topic, I will share some personal observations. Have you noticed that certain people go to the gym, eat right, and take protein supplements, and their muscles are still hardly visible? While others, who barely exercise and don’t watch their diets nearly as much, have lean well defined muscles and strong bodies? This led me to the idea that we all process nutrients in different ways, and therefore we must make close observations to what is happening in our system – even if physical and blood tests show that everything is balanced (including hormones).
What Makes the Body Not Absorb Nutrients?
Fiber isn’t just for helping you relieve yourself, it has a role in nutrient absorption too. One type of fiber in particular, called soluble fiber, from oats, beans and fruits, helps nutrient absorption. When soluble fiber reaches your gut, it forms a gel. As the gel goes through your intestines, it slows down food passage, giving vitamins, minerals and macronutrients adequate time to be absorbed. Without fiber, foods may travel through too quickly, which you’ll notice if you routinely have loose, watery stools.
It’s also possible to have too much fiber in your diet (this can easily happen to vegans, including me). Excessive fiber inhibits absorption of certain nutrients, so make sure you get just enough without going overboard. Every 1,000 calories in your diet means you’ll need 14 grams of fiber — 28 grams for a 2,000-calorie diet, the Dietary Guidelines for Americans 2010 states.
Celiac disease is an autoimmune disorder that causes your immune system to panic when gluten is present in your body. Gluten is a generally harmless protein in wheat, rye, barley and products coming into contact with these grains. With celiac disease though, your immune system thinks gluten is dangerous and goes into attack mode. As a result, your system starts destroying the villi that line your intestinal tract. Because the job of villi is to absorb nutrients as they pass, if you have celiac disease and continue to consume gluten, nutrient absorption diminishes as villi become damaged.
If your bowels aren’t functioning properly, no matter how balanced your diet is, you won’t be absorbing all of the nutrients you need. Crohn’s disease, diverticulitis, inflammatory bowel disease and colitis are just a few of the conditions that lead to inflammation in your intestines. Certain foods may trigger inflammatory outbreaks, causing damage to villi and intestinal walls, although sometimes inflammation stems for unknown reasons. If you undergo bowel surgery and have to part of your intestinal tract removed, nutrient absorption becomes further inhibited, since most nutrients absorb in your intestines.
Lactose Intolerance (not applicable for vegans, but good to know!)
Lactose is a natural sugar from dairy that breaks down with a specific enzyme called lactase. If your body doesn’t produce enough lactase though, you can’t digest lactose. You’ll experience abdominal cramping, bloating and diarrhea in as little as 30 minutes after consuming a lactose-containing food, the University of California San Francisco Medical Center explains. By continuing to have lactose in your diet, the increased frequency of diarrhea could cause your body to quickly pass beneficial nutrients. Chronic diarrhea can even damage the walls of your intestines, limiting nutrient absorption.
Please take these into consideration when making a decision for your protein supplementation! Observe your body and don’t try to stick to another myth the vegan society is trying to instill on everyone – the ‘no supplements needed’ myth. I have personally discovered that I do need to use a protein powder, despite a healthy varied diet – this is what came out after experimenting with different approaches and making sure I don’t have any deficiencies. You are a different person, so this may or may not be applicable in your situation!
Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids. Washington, DC: National Academy Press, 2002.
Rodriguez NR, DiMarco NM, Langley S. Position of the American Dietetic Association, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and athletic performance. J Am Diet Assoc2009;109:509-27.
Mangels R, Messina V, Messina M. The Dietitian’s Guide to Vegetar-ian Diets, 3rd ed. Sudbury, MA: Jones and Bartlett Learning, 2011.
Sellmeyer DE, Stone KL, Sebastian A, et al. A high ratio of dietary animal to vegetable protein increases the rate of bone loss and the risk of fracture in postmenopausal women. Am J Clin Nutr 2001;73:118-22.
Knight EL, Stampfer MJ, Hankinson SE, et al. The impact of protein intake on renal function decline in women with normal renal function or mild insufficiency. Ann Intern Med 2003;138:460-7
Dea is passionate about pursuing gentle, pure living in all its forms. She’s a veg and fruit foodie, who loves to explore the healing properties of plant-based foods and then fully indulge in their sun-filled taste. She believes that “In the end, only three things matter: how much you loved, how gently you lived, and how gracefully you let go of things not meant for you.”