Plant-based vs meat-based diet: What is gained and what is lost?
I want to preface this article by saying I am not a registered dietician or nutritionist. If you are looking for professional help in regards to nutrition, seek out a dietician or nutritionist; they will be able to help with creating tangible goals and provide you with a quantitative approach. With that being said, our diet plays a vital role in the performance of our bodies, so as a professional in the field of physical performance, it is crucial that I am educated on the truth behind nutrition to better serve my clients. The rising popularity of plant-based diets has led me to conduct in-depth research to discover the truth behind how meat affects us, both in its absence and presence. In this post, I will discuss what I found and how it applies to various activities and sports. First, I will discuss some foundational information behind what makes a protein complete, the difference between essential and non-essential amino acids, different food sources (plant and animal based) that are high in complete protein, how much protein our bodies need and the side effects of too much or too little. Second, I will get into the negative vs positive side effects of meat, the important role that hemoglobin plays in our body, how to properly regulate it, and what the side effects are if we have too much or too little. Third, I will cover how to optimize performance through diet, which is very dependent on the activities the body is engaged in, as well as the intensity and volume of those activities.
A complete protein is a protein that contains all nine of the essential amino acids. Essential amino acids are deemed “essential” because our body does not produce them. Therefore, we are required to obtain them through our diet. Non-essential amino acids are exactly the opposite, they are produced inside our body, meaning we don’t need to ingest them. As previously stated, there are nine essential amino acids that we need to ingest to ensure we are meeting our daily protein requirements. They are lysine, histidine, valine, isoleucine, leucine, phenylalaline, threonine, methionine, and tryptophan. Three of these are branch chain amino acids (aka BCAA’s), defined by their chemical structure; leucine, isoleucine, and valine. While most amino acids are oxidized in the liver, BCAA’s are oxidized in skeletal muscle, making them a primary contributor to muscle growth. Animal protein contains adequate amounts of all these amino acids, while plant-based protein often contains an inadequate amount of at least one amino acid or more. Methionine, leucine, and isoleucine are the amino acids that are often times lacking in a plant-based protein source. This is important because all three play a vital role. Isoleucine helps support muscle growth through limiting the muscle protein breakdown and promoting muscle protein synthesis. Leucine plays a similar role, but has an even greater effect. Methionine plays the role of increasing our metabolism, regulates the availability of folic acid, and also assists with protein synthesis. This doesn’t mean we can’t receive them from plant-based foods, it just means we have to be aware of what foods are high in these amino acids. These foods include soy, beans, peanuts, and corn. I won’t include specific sources of meat because meat contains a high amount of all the essential amino acids. All the hype surrounding protein has driven our protein consumption to unhealthy levels, causing side effects such as constipation, a constant release of toxins (excess farting), dangerously high hemoglobin levels that eventually lead to heart problems, and an increased workload for our kidneys and liver driven by the fact that we don’t store excess protein. All of this leads to imbalances that are very uncomfortable and eventually extremely harmful. Everyone’s protein requirements are going to be different based on their weight and activity level. The recommended daily intake is 0.8-1.8 grams/kg of body weight. Where we fall on that scale is directly dependent on our activity level for that day and days surrounding it. For example, I weigh 160 pounds and my activity level varies depending on the day. On less active days I consume between 50-70 grams of protein, while on my most active days I am consuming between 90-120 grams of protein. When we don’t meet our protein requirements we often will feel fatigued, experience more muscle protein degradation (muscle breakdown) and less muscle protein synthesis (muscle building), making it harder for us to progress our performance. Being aware of our protein intake and its direct correlation to our level of activity is crucial to optimizing performance.
Meat. We know that since the beginning of humanity, meat has played a vital role in increasing the size of our brains and every other muscle in our body. However, as we have entered into the age of science, research has begun to show the negative side effects that meat can have on us, but we can’t let that blind us from the benefits it has as well. Protein from meat contains two things that plant-based protein does not, heme iron and vitamin B12. Heme iron is more easily absorbed by our body than non-heme iron, increasing our hemoglobin levels and in turn, improving the transportation of oxygen via our red blood cells. Red meat, such as steak, contains higher levels of heme iron than non-red meat. However, an over-consumption of iron can drive our hemoglobin levels to reach extremely unhealthy levels, eventually leading to heart problems and other negative side effects. Another side effect of over-consuming meat is an increase in cholesterol build up on the arterial walls from an over-consumption of saturated fats. So the common life mantra of creating balance is no different in our diets. Meat can be beneficial to us if consumed in very controlled quantities. Keep in mind that the purpose of eating meat is centered around the ease of access to a complete protein and the increased absorption of iron through obtaining heme. As long as we put effort into learning which amino acids we are receiving from our various plant-based sources, we can manage a plant-based diet, supplemented by minor quantities of meat. Personally, I include meat in about 2-3 meals per week on average. This is enough to harness the benefits of maintaining a healthy hemoglobin level, but protects against reaching an unhealthy level, and in turn avoiding all the negative side effects. Is it possible to maintain healthy levels with a vegan diet? Yes, but it becomes much more difficult and tedious. Vitamin B12, one of our more important vitamins, is also only obtained through animal sources, but it is shocking how little meat we need to meet our daily B12 intake. Only 1.3 ounces of beef, a couple ounces of fish, or 7 ounces of chicken is needed to meet the RDI for Vitamin B12.
How do we apply these foundational truths into our diets and use this knowledge to drive progression in our performance? A great example is found in the sport of mountaineering, where athletes often find themselves in high altitude environments. The body has a harder time transporting oxygen at higher elevations, so we have to go through an acclimatization process, allowing our hemoglobin levels to reach a point where they can transfer oxygen at an efficient enough level. Knowing this, its important for a mountaineer who is preparing for a high altitude climb to begin altering their diet to better prepare for the acclimatization process. In regards to other sports, diets will vary depending on the goal. For endurance athletes, they don’t have to worry about maximum power output, but instead they have to put most of their attention on their ability to transport oxygen to increase aerobic performance. Power athletes involved in sports such as football, powerlifting, sprinting, and throwing require greater protein intakes to fuel the recovery needed for maximum muscle growth. Endurance athletes need a higher level of carbohydrates to fuel the longer duration of their workouts. Changes such as these are the key to maintaining a strict training regime and maximizing performance. As volume and intensity increases in a training program, the level of calories will increase, along with specific levels of protein, carbs, and fats to maintain the balance necessary for continued progression. Finding the balance that works best for our individual goals and needs is the key to optimizing our diet. If you are looking to build a nutritional plan, seek counsel from a dietician or nutritionist. They will be able to assess your nutritional needs and build you a personalized plan specific to your goals.
Dietary Heme Iron Absorption, A Discussion of Possible Mechanisms for the Absorption-Promoting Effect of Meat and for the Regulation of Iron Absorption, L. Hallberg, E. Björn-Rasmussen, L. Howard & L. Rossander, Pages 769-779 | Received 22 Mar 1979, Accepted 02 May 1979, Published online: 23 Feb 2010
The amino acid composition of proteins and foods. Analytical methods and results., Author(s) : BLOCK, R. J. ; BOLLING, D. , Book : The amino acid composition of proteins and foods. Analytical methods and results. 1945 pp.xiv + 396 pp.