How Much Protein is Too Much Per Day?

There seems to be a lot of confusion with protein intake. From warnings of kidney failure and cardiovascular disease, it’s no wonder people are apprehensive about eating too much protein. The FDA recommends a protein intake of 0.8 grams/kg of body weight. Is this enough, and how much protein is too much per day?

How Much Protein Should You Eat?

For a regularly exercising individual, I recommend a protein intake of 1 gram per pound of body weight. If you are overweight, you can base your intake off of lean body mass instead. While even higher intakes have been shown to provide benefits, this intake will provide you with all the essential amino acids necessary to repair and build muscle tissue.

Protein is present in every cell of your body. It is the second most abundant molecule in the human body – only behind water. Protein makes up your hair and skin, and is a precursor for the production of neurotransmitters. These neurotransmitters affect everything from mood to fat loss. It’s much better to err on the side of too much protein than not enough.

What about preventing muscle loss when dieting? A protein intake of 1 gram per pound of body weight was significantly superior to the FDA’s RDA of 0.8 grams/kg of body weight at maintaining lean body mass [1]. Given how important muscle is for losing fat, it’s even more imperative that you are getting sufficient amounts.

Can protein actually help with fat loss? Increased protein intake is correlated with increased fat oxidation independent of body weight [2]. In other words, increased protein intake caused a more favorable body composition. Simply eating more of your calories from protein can increase fat loss.

Are the FDA’s Recommendations Enough?

Based on the FDA’s recommendation of .8 grams/kg of body weight, a 150 pound person would need to consume just 54 grams of protein per day. That is just 10-15 percent of your calories coming from protein. Eat an 8 ounce piece of meat in one of your meals, and you’ve met your intake for the entire day. Can you survive on 54 grams of protein? Yes, but are we just trying to get by, or are we trying to optimize our performance?

Then there’s the potential health risks of “high” protein intake…

Warnings of kidney disease are overblown. In healthy subjects, protein intake does not significantly affect kidney function [3]. The majority of studies done on protein intake and kidney disease are done on patients with chronic kidney disease (CKD). In the case of CKD, protein intake should be monitored closely. In otherwise healthy individuals, a higher protein intake has not been linked to kidney problems. Will a higher protein intake mean that your kidneys have to work more? Of course, but just like how exercise makes your heart work harder, it doesn’t necessarily mean that it’s bad for you.

How Much Protein is Too Much Per Day?

So we know how much protein to aim for to optimize body function, but how much protein is too much per day? There are a few factors that will influence your protein intake. These include:

• Do You Exercise? – A higher activity level demands a higher protein intake. Muscle is made up of protein. When you exercise, you break down this protein and then build it back up bigger to cope with the increased stimulus. The more active you are, the higher your protein demands will be.

• How Many Carbs Do You Eat? – Carbohydrates are protein sparing. When glucose is present, protein is less likely to be broken down and used for fuel. If you are on a low carbohydrate diet, your protein intake should be higher than someone who eats several hundred grams of carbohydrates per day.

• Are You Trying to Lose Weight? – If you are, protein demands will be higher, or maybe I should say more important. Many people believe just the opposite – that you should have more protein if you are trying to put on muscle. While this might be true to an extent, in a hypercaloric environment, protein is spared much more than in a calorie restricted one.

Given all the variables, it’s not possible to give a blanket recommendation on how much protein is too much per day. Anyone giving you a number is simply making an educated guess. If you want that number, you are going to have to eat a controlled diet and then test for urea content. Your kidneys are responsible for the excretion of urea, and elevated levels usually mean more protein is being consumed than can be used. Even still, urea is just one of many markers to check for.

If I had to make my own educated guess, I would surmise that an intake approaching 1.5 grams/lb of body weight would start hitting the ceiling on the potential benefits towards athletic performance. Anything more would either be oxidized and excreted, or be converted to glucose or ketones to be used for energy. While there can still be benefits to even higher protein intakes, you begin to reach a point of diminishing returns. Aim for 1 gram per pound of body weight. For active individuals, it strikes a good balance between what is needed for optimal performance, and what is needed for good health.