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Posts tagged ‘Kidneys’

Protein: part 2

Hey guys, so in the first part of proteins, I talked about what they are and why they are so important. I also mentioned that we should be consuming a little bit more than the recommended daily intake, especially if we exercise. Now, I will explain why that is.

You see, your body is constantly building up and tearing down tissue. When there is tissue growth it´s called anabolism, and when there is tissue breakdown, it´s called catabolism.  When we exercise, especially resistance exercise (that is with weights), we are creating tissue damage, in other words CATABOLISM. To recover from that ¨catabolism¨, the body uses hormones and nutrients (proteins) to recover itself and build up more muscle (1). If we don´t have proteins at that moment, the body breaks down tissue (catabolism) somewhere else to get those amino acids……. in other words you could be losing muscle tissue!! The opposite of why most of us train and also really bad for those who want to lose weight.

When we consume proteins, that stimulates protein synthesis (build-up), and can reduce protein breakdown (catabolism) (2). But how much should we consume? Well, according to a recent study the greater the amount of protein individuals consumed, the greater the overall anabolic response. And when individuals consumed 80% of their daily protein in a single meal, it caused a greater overall anabolic response for the day than when the protein was split up over several meals (2). With all this said, there is still no consensus on how many grams of proteins you should consume per day but you should take into account a couple of things:

  1. If you are consuming a caloric surplus (taking in more calories than you are spending) you will require less protein.
  2. If you are in a caloric deficit (to lose weight, you consume fewer calories than what you burn), you will need more protein, so that you don´t lose muscle (4) Mettler et al. 2010)
  3. Women are better able to preserve lean mass (muscle) compared to men during times of reduced caloric intake (3)
  4. And lean individuals in a caloric deficit need more proteins than overweight individuals (4). So, if you weigh 80 kilos and have a lot of muscle, you will need to consume more  proteins than an 80 kg man who is ¨overweight¨ or has very little muscle.

With all this said, the ¨experts¨ recommend taking in between 0.70-1 gram per pound (5).

Now let us get to the topic if too much protein is bad for the kidney.  Within wide limits, there is no evidence that a diet high in protein has any detrimental effect on those with normal renal function(6-8). Now, if you have problems with your kidneys you should NOT be on a diet high in protein. Also, a recent study done in a Spanish university said a diet high in proteins increases the changes of experimenting renal dysfunction (click here). However, this study was done in rats and they were on a diet where the proteins represented 45% of that diet!! The normal recommendations are that proteins should represent just 10%,  45% is 4 times the recommend averages! So of course, I don´t think that is healthy. On top of that I don´t know how much the rats where exercising.  With all this said, I still think that people who want to lose weight should be on a diet high in protein, also those that exercise or are active. On the other hand, those who are  couch potatoes have no reason to be eating more proteins.

Hope you guys liked it. Till next time!


  1. Kumar V, Atherton P, Smith K, Rennie MJ. Human muscle protein synthesis and breakdown during and after exercise. J Appl Physiol 2009, 106(6):2026-39.
  2. Wolfe R, Deutz N. Is there a maximal anabolic response to protein intake with a meal. Clinical Nutrition.2013.
  3. Lemon PW. Beyond the zone: protein needs of active individuals. J Am Coll Nutr.200 Oct;19
  4. Mettler, S., Mitchell, N., & Tipton, K. D. Increased protein intake reduces lean body mass loss during weight loss in athletes. Medicine and Science in Sports and Exercise, 2010.42, 326-337.
  5. Schoenfeld B. The Max Muscle Plan. Human Kinetics.2013
  6. Lowery LM, Daugherty A, Miller B, Bernstein E, Smurawa T. Large chronic protein intake does not affect markers of renal damage in healthy resistance trainer. The FASEB Journal.2011;25:983.25
  7. Lowery LM, Devia L. Dietary protein safety and resistance exercise: what do we really know?. J Int Soc Sports Nutr.2009 Jan12;6:3
  8. Martin WF, Armstrong LE, Rodriguez NR. Dietary protein intake and renal function. Nutr Metab (lond),2005


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