I hear conflicting advice on the percentage of protein in a healthy diet. How much protein should I be getting?
The subject of protein intake is, as you’ve noticed, a contentious issue. It’s gotten a lot of attention (and scrutiny) since the Atkins and derivative diet plans became all the rage several years ago. Let me first say that, while I can tell you my perspective on protein, it’s not a stand-in for your physician’s advice. Individual health history is crucial to determining appropriate protein intake, and your doctor will be able to look at the full picture with you.
That said, I think high protein diets get a bad rap for a number of reasons. Too many people approach a high protein diet as a free pass to eat whatever meats they crave, and that too often means fatty, cured, conventional meat. They also don’t balance their diet appropriately.
Protein should be lean and clean, as I always say: low in fat and free (or as free as possible) from the toxins of our modern food supply: pollutants (like dioxin in dairy), nitrites, growth hormones, antibiotics, pesticides from feed, and chemical sanitizers or irradiation used in processing. A healthy diet, by definition, means plenty of vegetables, fruits and varied protein sources such as eggs, fish, and a variety meats. Dairy products also contain protein, but I suggest limiting dairy and focusing on the above foods as the staples of a healthy diet.
First, let’s look at what conventional recommendations are. The current U.S. RDA for protein is 63 grams a day for the average sized male, or for your individual RDA, 0.80 g/kg/day (grams of protein per kilogram of your weight per day). Many nutritionists suggest that athletes and very active people can maintain their muscle mass at 1.0 g/kg/day. Most nutritionists say protein should constitute no more than 20% of your calories each day.
Now I’ll give you my perspective.
Based on latest research findings and in the context of the Primal eating strategy I talk about on the site, men and women can and do thrive on higher than conventional protein diets. Humans evolved with a high protein diet. Experts from the Medical Research Council at the University of College London estimate that, while the typical Western diet today is composed of 49% carbs, 35% fats and 16% protein, the diet of traditional hunter-gatherer populations included twice the protein intake.
Current study of tribal populations that maintain traditional diets shows that high protein, fruit and vegetable rich (virtually no carb and few unhealthy fats) “hunter gatherer” diets seem to protect against the “diseases of wealth” we experience in the developed world (i.e. many forms of heart disease, diabetes, certain cancers, etc.).
In keeping with this research, I don’t believe people need to limit their protein intake to 20% of their daily calories. The upper limit of protein recommendations is hotly contested in all circles. I, myself, try to get at least 1 gram per pound of body weight per day (165). I can survive on less, but I’m all about maintaining my lean mass. You can only do that with protein, and I don’t believe the current RDA allows for that, especially in active individuals.
One of the most common critiques links higher protein diets to impaired kidney function. Recent research suggests, however, that people without prior or developing kidney or liver impairment do not experience any kidney or liver issues with a higher protein intake (1.3 g/kg/day). People most at risk for this kind of kidney stress include those who have a personal or family history of kidney or liver problems or those who have high blood pressure or diabetes. (Because developing kidney and liver problems don’t always have obvious symptoms, it’s important for your doctor to know your protein intake exceeds conventional recommendations.) People with liver or kidney problems, doctors warn, are less able to process and excrete the waste products (mostly nitrogen left over from amino acid breakdown) that are produced when the body metabolizes protein.
I would repeat here that it’s important that you feed your body the “cleanest” protein you can. Animal products, meat and fish in particular, are the most protein-rich options, and they contain vital omega-3s. However, they also can carry the heaviest “toxic” burden of our modern food supply. These toxins are powerful and plentiful enough over time to put a strain on anyone’s body – including liver and kidneys. Choose organic, grass-fed meat and poultry whenever possible, and go for wild instead of farmed fish.
You might also hear that high protein diets can put you at risk for osteoporosis. This outdated claim simplifies the picture and doesn’t hold up well under detailed scrutiny. Most new research, including USDA studies, suggests bone density improves with added protein intake in most deficient or borderline people when they also have adequate Vitamin D. These findings are particularly important for older men and women, for whom the loss of bone density and muscle mass is of vital concern.
Other factors important for maintaining bone density include: salt consumption, magnesium to calcium ratio, sunlight exposure and Vitamin D deficiency, ph dietary balance, and physical activity levels. To protect your bone density, reduce salt (and salt derivatives) as much as possible, get plenty of sunlight, do regular weight bearing exercise and eat plenty of fruits and vegetables to balance both the acidity of many protein sources and to boost magnesium levels in your diet.
Sponsor note: This post was brought to you by the Damage Control Master Formula, independently proven as the most comprehensive high-potency antioxidant multivitamin available anywhere. With the highest antioxidant per dollar value and a complete anti-aging, stress, and cognition profile, the Master Formula is truly the only multivitamin supplement you will ever need. Toss out the drawers full of dozens of different supplements with questionable potency and efficacy and experience the proven Damage Control difference!
Mark Sisson is the founder of Mark’s Daily Apple, godfather to the Primal food and lifestyle movement, and the New York Times bestselling author of The Keto Reset Diet. His latest book is Keto for Life, where he discusses how he combines the keto diet with a Primal lifestyle for optimal health and longevity. Mark is the author of numerous other books as well, including The Primal Blueprint, which was credited with turbocharging the growth of the primal/paleo movement back in 2009. After spending three decades researching and educating folks on why food is the key component to achieving and maintaining optimal wellness, Mark launched Primal Kitchen, a real-food company that creates Primal/paleo, keto, and Whole30-friendly kitchen staples.