Nutrition Fads Under Review: Part 3 High Protein Diets

This question most commonly comes from very physically active individuals but more and more, it is starting to come into focus with people looking to lose weight; with good reason!

Are high protein diets good for you?  How much protein do you need in a day?

High protein diets are increasingly being used for weight loss, muscle growth, and post-exercise recovery.  However, how much protein we actually need and/or benefit from is up for debate.  While ‘higher’ protein diets have been shown to be beneficial, too much protein has been shown to have detrimental effects on bone mass and renal function.

The Dietary Recommended Intake (DRI) for protein is 0.8 gram per kg body weight per day.  Therefore, under these recommendations, a 60 kg (132lb) individual should aim for about 48g of protein per day.  This is the amount of protein needed to cover the requirements of 97.5% of the population in order to prevent a deficiency.  Note: preventing deficiency and achieving maximal benefit are very different.

The acceptable macronutrient distribution range (ADMR) for protein, however, is between 10-35% of total daily calories.  So if you do the math, a 60kg (132lb) woman eating approximately 2000 calories/day could have 50g – 175g of protein per day (10-35% daily calories).  Even the lower level of this is higher than the DRI!  The upper level is, over 3.5x times the DRI.  Anything above the upper limit (35% of total daily calories) is considered high protein.

So, what does this mean?  How much protein should you get every day? Well, again, it’s very individual however much of the benefits of dietary protein come above the DRI level.  This includes increased satiety, positive effect on body composition, greater diet-induced energy expenditure (uses more energy to digest), and weight loss.

Therefore, many individuals such as the elderly, pregnant, athletes (or high level of physical activity), or those trying to lose weight, may benefit from higher amounts of protein in the diet.  For healthy individuals (i.e. no renal disease) protein intake up to the upper limit of the ADMR is safe.  However, most consider 1.5-2g/kg of body weight sufficiently high to achieve whatever weight loss/body composition goals you may set out to achieve (ex. 90-120 g of protein per day for a 60kg (132lb) individual).

Remember, it’s all about balance and having variety in your diet every day.    If over 35% of your diet is protein, it leaves much less room for other wholesome foods which may be needed to achieve all your nutrition goals.

Best

Tara

Topics: Smart Eating, Nutrition, Weight Loss

Dr. Tara Coletta, PhD

Written by Dr. Tara Coletta, PhD

Tara's research focused on obesity and metabolism. She studied exercise science (MS, UMass Amherst) before earning a PhD in nutritional biochemistry (Tufts University). Wellness remains an integral part of Tara’s life as she works to balance being a mother of three.