People seem to panic when it comes to getting enough protein, particularly when I mention plant-based diets. Everyone seems to be worried about hitting protein requirements, even though I've never seen a case of protein deficiency in my 15 years of medical practice. We now have an abundance of research confirming that even vegans who aren't paying particular attention to plant-based sources of protein are still hitting their daily goals. I'm not suggesting we dismiss protein intake or minimize the potential risks of amino acid deficiency on plant-based diets, I'm simply stating that this whole protein panic has been blown way out of proportion. We tend to associate protein intake with health and strength and the health halo that surrounds this macronutrient has always intrigued me. At least we've avoided demonizing protein, like we've done with carbs and fat. The attention protein gets seems to distract us from other nutrients of concern, like fiber, or iron. We see these nutrient deficiencies regularly, yet everyone wants to talk about protein. In this article, I'll review protein, how it's made, what it does and why there's no need to panic!
Protein's Health Halo
Protein is one of our 3 macronutrients. It offers 4 calories per gram and we should be getting at least 10% of our calories from protein. To help with muscle repair and rebuilding, some athletes need more like 15% of daily calories coming from protein, and some strength and muscle building disciplines, like bodybuilding, may require up to 20% of calories coming from protein.
We've grown to believe that the more protein, the better, and clever marketing has convinced us that eating animals is the best way to increase protein intake. People associate high intakes of protein with health, and protein powders, protein supplements and other protein isolates are being increasingly consumed by non-athletes. Have we forgotten that by getting our most of protein from meat, we're also getting more cancer, more auto-immune conditions and more heart disease? We have become protein obsessed. Although a 0.8 gram per kg of lean body weight ratio is recommended by experts (which means a 70 kilogram person should eat 60 grams of protein per day), it's super common to hear of non-athletes consuming upwards of 100-120 grams of protein per day! Although protein is considered to be a relatively satiating macro (meaning that it makes you feel full), studies have shown that consuming excess protein doesn't necessarily lead to subsequent decreases in total caloric intake as much as fiber does. Protein excess simply leads to it getting broken down and transformed into carbs for energy use, or stored as energy for later use. Being a non-efficient source of energy, experts recognize that there is no logical reason to recommend excessive protein intake, since it does not seem to improve health outcomes.
I can already hear people getting angry with me. How dare I regurgitate peer reviewed research and evidence based recommendations when some personal trainers are recommending upwards of 200 grams of protein per day. Short term muscle gains at the expense of long term health and longevity. Last week, I had a 60 year old patient weighing 130 pounds telling me she ate 150 grams of protein from meat per day as per her trainer's recommendations. I'm guessing that he forgot to mention the insane amounts of cholesterol and saturated fats she was getting with all that meat, or hesitated to mention that she would likely be fiber, vitamin and antioxidant deficient. Let's not forget that processed meat is classified by the World Health Organization as a Group 1 carcinogen, and red meat as a Class 2a carcinogen. Protein coming from plants has the opposite effect, being protective against cancer and chronic disease. If you want to eat 200 grams of animal protein per day, then by all means go for it, but please don't recommend that others do the same by telling them this is a healthy practice.
How They're Built
Protein is made of amino acids, all joined together in a specific order. They're found throughout the body, in hair, muscles and bones. They make the enzymes that power most chemical processes keeping us alive and can also be used as fuel when needed. Of the 20 amino acids that make up protein, 9 are essential, meaning that our bodies can't synthesize them and they must be obtained in our food. The others are non-essential, meaning that our bodies can make them from scratch, or modify existing ones to make them.
The essential amino acids include histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. If you're eating a calorie sufficient diet coming from a variety of plants, then you're getting enough protein. The issue lots of people will raise is that meat contains "complete protein", meaning that it contains all of the 20 amino acids, including the 9 essential ones, in comparable ratios and sufficient quantities. Since most plant sources don't contain all 20 amino acids in comparable quantities, and some lack sufficient quantities of certain essential amino acids, some plant sources of protein is said to be "incomplete". I really dislike the term "incomplete" since people compare this to being "inadequate". When using the term "incomplete" protein, you're assuming that you'd get most of your daily protein needs from a single food source, which is a very unhealthy way of fueling your body. If you're reading my blog, I'm assuming health is a priority for you and you're not here to find out how to become a professional bodybuilder, considering they have an average life expectancy a few years shy of 50. Eating white rice and chicken everyday is a great way of getting lots of protein and also a surefire way of getting nutrient deficiencies. Keep in mind that in the protein synthesizing process, the human body will do exactly what all the other animals do. It will take what it needs from the day's amino acid pool, combine them and then make the protein it needs. In fact, all of the plants have different amounts and ratios of each and every amino acid, meaning that all we have to do is eat a reasonable variety of plants and the body will combine their amino acids to fill in the gaps. Think of the silverback gorilla, one of the strongest animal specimens on the planet, who feeds on leaves and shoots all day.
For educational purposes only, here are some examples of "complete" sources of plant-based protein:
soy (including tofu, tempeh and edamame)
In their research review, the authors looking at protein and amino acid adequacy conclude: "Overall, when diets are at least slightly varied, suggestions that vegetarians have to be sure to achieve a higher total protein intake than the RDA, or to pay strict attention to choosing plant foods with complementary amino acid patterns are simply over-precautious."
Animal Versus Plant Protein
Research clearly shows that the source of our protein is much more important than the amount, and protein comes pre-packaged with different compounds depending on its source. Animal sources of protein come packaged with inflammatory compounds, like saturated fat, heme-iron, cholesterol, sodium and zero fiber. Plant sources of protein come packaged with fiber, antioxidants, anti-inflammatory compounds, phytonutrients, zero cholesterol and almost no saturated fat. We can't forget that most animal products contain hormones and antibiotics. Also, our microbiome feeds off protein and then produces TMAO, a compound strongly linked to heart disease. Plant protein sources feed our good gut bugs, and lead to the production of short chain fatty acids, which are protective compounds linked to gut health and health in general. Your body digests protein into its elemental components, amino acids. Once broken down into amino acids by your digestive system, your body can't tell whether the amino acid came from animals or plants, but it can tell what other nutrients came with it.
In terms of calorie density, animal protein has an average of 1000-2000 calories per pound of food, versus plant sources of protein which have a calorie density closer to 200-600 calories per pound of food. After looking at over 3000 different types of foods, researchers estimated that plants contained 64 times more antioxidants than animal products. Lots of baggage comes with animal protein, and on top of the excess calories, cholesterol, saturated fats, carcinogens and lack of fiber, we must also include the devastating environmental impacts and cruel mistreatment of animals. Here's a quick comparison of different sources of protein:
A 4-ounce broiled sirloin steak is a great source of protein—about 33 grams worth. But it also delivers about 5 grams of saturated fat.
A 4-ounce ham steak with 22 grams of protein has only 1.6 grams of saturated fat, but it’s loaded with 1,500 milligrams worth of sodium.
A cup of cooked lentils provides about 18 grams of protein and 15 grams of fiber, and it has virtually no saturated fat or sodium, and is filled with prebiotics, vitamins and minerals like iron.
The following plant foods are also packed with protein:
¾ cup of seitan (21 g)
1 cup cooked lentils (18 g)
1 cup edamame beans (18 g)
¾ cup tempeh (18 g)
¾ cup tofu (16 g)
¾ cup beans (16 g)
¼ cup hemp seeds (13 g)
¼ cup chia seeds (7 g)
1 cup of soy milk (7 g)
¼ cup of almonds (7 g)
¼ cup cashews (6 g)
2 tbsp peanut butter (8 g)
½ cup cooked quinoa (4 g)
½ cup cooked oats (4 g)
Protein Requirements For Athletes
For athletes, the evidence clearly shows that plant protein is as effective as animal protein in terms of muscle and strength building potential. Even though the science is out there and available for all to read, non-athletes still tend to consider protein supplements, like whey protein, a health food. Corporations, to minimize waste and increase profit, needed to find a way to reuse the milk proteins, casein and whey, which are by-products of cheese making. Cue protein powders that were marketed to athletes as the magical protein solution. Little did they know that these 2 milk proteins are now linked to increased risk of hormone dependent cancers, like breast and prostate cancer. Other animal sources of protein have been found to increase systemic inflammation and oxidative stress, which in the long term, will increase risk of many inflammatory, allergic and chronic medical conditions, including cancer. In fact, the World Health Organization has issued a statement that meat and particularly processed meat, is linked to increased risk of cancer. Processed meat is classified as a Group 1 carcinogen, meaning that the level of proof linking both is as strong as the association between smoking and lung cancer.
Now let's not kid ourselves. Even though most guidelines speak of a 0.8 gram per kg of lean body weight, that's for adequate levels of protein. What about optimal levels? If 100% of your protein is from whole plant sources, many experts agree that increasing your protein requirements by 10% would compensate for their lower digestibility attributable to their high fiber contents. Although making protein a little less digestible, its high fiber content makes it a lot healthier. It is highly associated to improved gut health and reductions in the rates of almost all chronic diseases. Athletes also require increased protein intake to make up for the muscle damage and repair that happens at every workout.
Endurance athletes should consume 1.2-1.4 g/kg/day.
Strength athletes 1.2-1.7 g/kg/day.
As stated earlier, plant-based athletes could increase protein intake by 10%, for a recommended intake of 1.3-1.8 g/kg/day.
Lysine - The Limiting Factor
Lysine is an amino acid that's found in lower amounts in plants than all of the other amino acids. If you're vegan or largely plant-based, you want to give some attention to your Lysine intake, since insufficient intakes are more likely in those eating insufficient calories or eating a minimal variety of plants. Foods that contain higher amounts of Lysine include tempeh, seitan, lentils, quinoa, pistachios, and pumpkin seeds. You can also find them in most vegan plant-based protein powders. That being said, studies show that in the person eating enough calories and even a small variety of plants, Lysine deficiency is rarely seen. I'll detail this even more in my next blog post.
Protein powders are a convenient and quick way to hit your protein goals without having to fill up on additional plant foods. If you're going to use one, make sure you're not consuming excessive amounts of protein. These, contrary to popular belief, don't confer any magical properties. You're much better simply counting your daily requirements based on lean body mass and activity level, and determining the number of grams you need. Then, you can choose to log in your meals in apps like Cronometer or My Fitness Pal to see if any adjustments should be made. If you're going to choose a plant-based protein powder like me, consider one that uses a plant protein blend. By using various blends of plants, like pea protein, brown rice, hemp or soy, you get a better variety of amino acids, also called a wider amino acid "profile". I personally use plant-based protein powders when I'm looking for 20-25 grams of quick and convenient protein without wanting to fill up on fiber rich plant-based protein sources like legumes. Keep in mind that to build muscle, you need resistance training, while consuming adequate protein and excess calories, not excess protein. That being said, athletes do require higher daily amounts for proper performance. I aim for 1.6 g/kg per day, and although I haven't logged any foods in years, I did log them early in my transition and had no issues hitting my protein goals. Protein powders should never be used in replacement of eating actual nutrient dense foods. When your nutritional requirements are being met through whole foods, they probably serve little purpose. The exception would of course be in the athlete looking for a caloric restriction while maintaining muscle mass. In this specific situation, a calorie poor, yet protein concentrated supplement could be useful.
When comparing plant-based protein powders and whey protein powders, studies show almost identical absorption rates. Anabolic effects are also identical as long as serving size and leucine content is matched. Leucine is an amino acid specifically associated with the anabolic effect of ingesting protein. Plant-based protein isolates are as good as the "gold standard" which has always been whey protein, when looking at performance and muscle protein synthesis. Look for a powder that has 20-30 grams of protein per serving and contains 2 grams or more of leucine.
My Plant Prescription
So whenever possible, consume plant sources of protein to avoid the inflammatory compounds in animal products, and to consume the anti-inflammatory ones in plant sources. It will help you avoid chronic diseases, and have improved health outcomes. If you're an athlete, have no fear, because if you're eating enough calories of a variety of plant foods, you're getting sufficient and high quality protein.
Protein is super important and I hope no one thinks I've been minimizing that. It contributes to the growth and repair of all tissues and organs. Although we associate protein with muscles, it also plays an important role in immune function, enzyme synthesis and overall health, but somewhere along the way, the message of more is better got accepted as the norm. Sufficient or adequate amounts of protein are necessary, but in amounts much smaller than we're led to believe. While the recommendation for the average Joe is 0.8 grams of protein per kilogram of body weight, we still see non-athletes eating upwards of 100-120 grams of protein per day, believing that this is a healthy practice. The marketing of protein supplements and whey powders were initially directed at athletes, but now are pitched as health supplements for anyone who can pay for them.
Lay off the excessive protein intake, and consume as much plant sources of protein as is practical for you, since they come packed with beneficial nutrients and lack some of the bad stuff that comes with animal protein. To ensure our body gets all the amino acids it needs to build complete protein from all 20 amino acids, including the 9 essential ones we must get through diet, try eating a variety of plant sources of protein, like soy products, legumes, whole grains, nuts and seeds, and the right amount of grams of protein, carbs and fat will magically fall into place. I don't count calories and I don't count grams or protein or of any other macronutrient for that matter. I simply eat whole foods 95% of the time until I'm full and supplement with a plant-based protein powder when it's convenient for me.
Check out my website plantbaseddrjules.com and look for the “How To” section in the menu. There, you’ll find tips and tricks that helped me on my journey towards a plant-predominant diet. Everything there is completely free, no catches! If you're looking for healthy high protein plant-based recipes, check out plantbaseddrjules.com and download my free recipe eBook!
Look for me on the socials, @plantbased_dr_jules on Instagram and go like my Facebook Page, Plant-based Dr. Jules. If you’re looking for some fitness motivation and are curious to see what a plant-based athlete can accomplish, follow me, @maritimeninja, on my fitness account on Instagram or check out my fitness group on Facebook, called Maritime Ninja Warrior.
Thanks so much for reading!
Plant-Based Dr. Jules 💚🌱
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