How much protein one should consume is a highly debated subject. A quick search on the internet will result in numerous articles on this topic with varying points of view which can be overwhelming and confusing. I’ve had the opportunity to study several points of view on protein consumption in my nutrition program and will share some of those views with you in this article as well as provide you with my own perspective on protein consumption.
Firstly let’s start with the basics. Protein is one of three macronutrients. The other two being carbohydrates and fats. Proteins are made up of amino acids and differ chemically from fats and carbohydrates in that they contain a nitrogen molecule in addition to the carbon, oxygen and hydrogen molecules which exist in all 3 macronutrients. Even the number of amino acids that exist is up for debate. I have seen numbers ranging from 20 amino acids to as high as 28. The reason for the variation in amino acid number has to do with what amino acids are being included as part of the count. Some of the amino acids are not found in body proteins (e.g. Citrulline or Carnitine). Others are not produced during protein synthesis but they are still amino acids. So if you include those amino acids in your count then the number will be on the higher end. I won’t go on in any further detail because that would require a lesson in biology and would take up a full article, or two, on its own. Most people agree on 21-22 amino acids. Of these amino acids, 9 are considered essential, meaning the body must obtain them from food.
There is no disputing that protein plays an important role in our bodies. It makes up the structure of every cell and tissue in your body including your muscles, skin, tendons, hair and nails. Protein is required for growth, repair and new tissue development and in making body enzymes and hormones.
While there are some differences in the amount of amino acids reported, the biggest source of controversy around protein is how much we should be consuming and the health risks associated with consuming high protein diets. The generally accepted recommended daily intake of protein is around 0.75g/kg of body weight. This is probably a reasonable average number, but it’s just that – an average. It really doesn’t account for athletes or those who are engaged in regular and more intense physical activity.
People who exercise regularly require additional protein to compensate for the increased breakdown of protein during and immediately after exercise and to assist with tissue growth and repair. The amount of protein one should consume depends on the intensity and the duration of the exercise. Strength trainers, for example, have higher protein needs compared with endurance athletes because there is significant protein breakdown and build up after exercise and a greater demand for tissue repair.
Studies suggest that strength trainers should consume around 1.4-1.8g/kg of body weight (Williams, 1998; Bean 2012). I’ve also seen ranges as high as 2.0g/kg of body weight and slightly more. If you are on a weight gain diet and are strength training intensively then in my personal opinion I think you can consume on this higher end. Endurance athletes do not have as high a protein requirement as strength trainers. Research shows that endurance athletes with moderate to heavy training can consume in the range of 1.2-1.4g/kg of body weight (Williams 1998; Bean 2012). These levels are nowhere close to the generally recommended amount of 0.75g/kg of body weight. If you are a regular exerciser engaging in strenuous activity, you would be under consuming protein and would likely be losing rather than gaining or maintain muscle.
If you eat more protein than the above guidelines is that a bad thing?
No not necessarily (though again this is a hotly contested topic). You have to consider your total calorie intake as well. If you are consuming more protein than you need and it’s resulting in greater calories than required then you are going to gain weight (and not in the form of muscle). So in this case, consuming more protein isn’t good. Remember consuming more protein will not result in muscle gain. The way to gain muscle is through optimal protein intake combined with strength training at the right intensity.
Two well documented areas of concern with higher protein diets is whether you will harm your kidneys or impact your bone health.
Higher protein diets have been associated with kidney harm because when protein is metabolized it produces ammonia which is toxic to the body. The ammonia is converted by the liver into urea which is nontoxic and is then carried through the blood, filtered by the kidneys and excreted in urine. (If you consume a lot of protein, you need to consume a lot of fluid to assist in this process and to counter act the water lost). The theory is that this filtering process causes your liver undue stress due to the additional work. Other theories, believe that as long as you are healthy and do not have any issues with your kidneys a higher protein diet should not be of any concern. I tend to agree with this position, provided your protein intake isn’t unreasonably high and you are sticking within the guidelines as referenced above.
The theory behind protein consumption and bone health has to do with the fact that when protein is digested it creates an acidic state in the body. The pH of the body must be maintained within a very narrow range because critical enzymes can only perform their tasks correctly in the correct pH environment. A pH of 0 is totally acidic, while a pH of 14 is completely alkaline. The ideal pH for the body is approximately 7.4, which is close to neutral (a pH of 7 is neutral). When the pH starts to drop below this point (meaning the body is more acidic), our bodies natural buffering system kicks in to maintain the ideal pH state. In order to neutralize the acid resulting from protein consumption, calcium and other alkalinizing minerals are said to be removed from our blood, bone and tissues resulting in demineralization and ultimately bone loss. However, some studies have suggested that although additional calcium is excreted in the urine, there is no evidence to suggest it comes from the bones. My take on this one is again to keep within a reasonable limit on your protein consumption and to counter act the acidic state by consuming alkalinizing foods like fruits (except dried fruits), vegetables, almonds, and sprouted seeds. I think the jury is still out on this one and there is still more research required.
As I conclude this article, it is of my personal opinion that too much of anything is not a good thing, whether it be protein or any of the other macronutrients. I hope that this article helped demonstrate the varying views on protein consumption and that the amount of protein that is appropriate to consume varies based on a person’s exercise regime and health status. Remember, what is appropriate for me (or someone else), may not be for you. Each person is unique so you would have to experiment and find the right amount for you.
To fitness with love,