Biomedical Engineering

I agree on the mentioned ratios. 1-1.5 grams of protein per pound of lean body mass is ideal for someone who is dieting, training, and performing cardio and wants to make sure they are sparing muscle tissue from being catabolized for energy.

But let's not knock protein shakes! The Biological Value Scale (BV) and the Protein Digestibility Corrected Amino Acid Scale (PDCAAS) rate protein quality by molecular weight and digestibility and tells us how much of the protein will be used by our body.

Meat sources rank lower because they are not as easily digestable compared to an isolate whey protein shake for example. The isolate whey is processed, it is lactose free, more pure, lower molecular weight, breaks down and gets absorbed better.

I am not knocking whole food either. A combination of whole food and protein shakes is the best. Whole food will fill you better while a protein shake is more convenient and when needed you have quickly and easily digestable proteins available to you.

Only when you specifically want to add muscle mass like with bodybuilding or sports that strain the muscles heavily would i advise on using protein shakes (or supplements) if you just do normal fitness or are a casual trainer. a normal healthy diet should be enough.

Epke,

I have to agree and should have been more specific about that in my response. But if you are eating a normal healthy diet consisting of maybe 5-7 smaller meals evenly spaced throughout the day protein shakes are very convenient compared to eating that many whole food meals.

Normal diets very per person. Eating when your body tells you to rather than when you can or want to helps.

And I know from experience that when you are exercising for muscle and strength or even have a hard labour type job, your body tells you to eat all of the time!

Add a cup of lentils to a normal diet and you are likely offering all the protien that your body can proccess in a day. I cook them with water, 1/2 a medium onion and, 1 tsp of canola oil. Balance carbs to stay at a static weight.

According to Michael R. Eades, M.D. and Mary Dan Eades, M.D. in their book "Protein Power", your minimum protein requirements are based on your lean body mass and activity level factor (grams/lean body mass). Multiply your lean body mass by (0.5 – sedentary, 0.6 - Moderately active, 0.7 – Active, 0.8 – Very Active, and 0.9 – Athlete). In their book they give more detail explanations for the activities. So it seems you would fit into the Athlete category. First, determine your lean body mass (let's say 115 lbf) and then multiply by 0.9 gram/lbf to give 103.5 grams of protein per day minimum to be able to maintain your current lean body mass. This is only a minimum requirement for your body to maintain its lean mass. Eating more protein may or may not cause weight gain depending on a variety of factors. According to Eades, unless one is eating an enormous amount of excess calories, but is on a low carb diet, it's difficult to actually gain weight. Your body will not store the excess, but will pass it.

Most of your links do not have any source reference other than some doctor said so. They may be experts, but they may also be incorrect. What do the studies say? And are those studies or the conclusions of those studies valid?

You state "Excess protein can also result in kidney and liver damage, dehydration, and nutrient imbalance". What is your source? I don't recall seeing that documented in the links you provided. I do agree that excessive protein may cause one to become overweight as body composition depends on many factors (exercise, caloric intake and dietary composition). But do you have a reference (something other than an observational study) that supports this claim?

Regarding the second link, Dr. Eades has a number of blogs on his website (www.proteinpower.com) where he discusses the topic of excess calories vs. carbs as to which is responsible for weight gain. While weight gain may be due to excessive caloric intake, if you are eating a high carb diet, it is very easy for that to drift into being a high caloric intake diet. However, on a low carb diet, one generally get's sufficiently satiated with fewer calories. Another aspect is that there is a change in metabolism associated with eating a low carb diet. The body's metabolism increases so without a reduction in calories at all, the body will burn more thus resulting in weight loss.

I apologize that I left this link out of my resources: http://www.ific.org/foodinsight/1998/so/proteinfi598.cfm

You said it yourself. Protein breaks down into carbs (and so do fats). The resulting insulin spike and glucose in your blood can fuel your muscles. Haven't you heard of Atkins and Ketogenic diets?

I think a more accurate way to put it is that proteins can be convert to glucose. As a matter of fact....not all protein is.....only excess protein. And I don't believe it results in an insulin spike, but a slower release of insulin. That is why protein and low carb is better for diabetics. As a matter of fact, it's better for the general population too in that it will reduce insulin resistance that comes with a high carb/low fat diet that has been pushed for decades (only to result in higher obesity, increase in diabetes, increase in heart disease).