The most popular diet out there right now is the ketogenic diet. Basically, it eliminates all starchy carbohydrates (rice, pasta, potatoes) and the body is forced to burn fat rather than the carbohydrates it isn’t getting. Most low-carb or ketogenic dieters eat a lot of protein, particularly meat. Is there an amount that is just too much? How much protein does a human being actually need on a daily basis?

Let’s take a look at some of the science around that question.

What good is protein?

First, let’s look at what protein actually does for your body. An article in Popular Science explains that protein is broken down into amino acids, then other proteins are built, including muscle. (That’s why bodybuilders typically eat very high protein diets.) Protein also builds bones, cartilage, blood, and skin. Your fingernails and hair are mostly made from protein, too.

Protein is a macronutrient – lots of it is needed for the body to function well. According to another source, WebMD, although your body needs a lot of protein, it doesn’t store it. Fats and carbohydrates are stored. The article notes, however, that it’s a myth that we need more protein to build more muscle, though – the note that muscle is only built through exercise.

WebMD recommends the following amounts of protein be consumed for maximum health in a day: seven ounces (198 grams) for teenage boys and for active men, five ounces (141 grams) for women, small children, and older people, and six ounces (170 grams) for most women and men and older children. It’s better if the protein comes from something other than animal flesh, which is often high in saturated fat.

Protein for sedentary people

Should age be the way we determine how much protein to eat every day? As we all know, men and women sometimes have huge variations in what they weigh. The Popular Science source says you should eat .8 grams of protein per kilogram of body weight each day. (Put another way, .03 ounces of protein per 2.2 lbs. of weight) So a person weighing 150 lbs. (68 kilograms) should eat 2.4 ounces (or 54.4 grams) of protein a day if they are relatively sedentary or their only daily exercise is walking.

The Recommended Daily Allowance, as noted in the Harvard Medical School blog is .8 grams of protein per kilogram of body weight. Put another way, “For a 50-year-old woman who weighs 140 pounds woman and who is sedentary (doesn’t exercise), that translates into 53 grams of protein a day.” However, they caution, “The RDA is the amount of a nutrient you need to meet your basic nutritional requirements. In a sense, it’s the minimum amount you need to keep from getting sick — not the specific amount you are supposed to eat every day.” In other words, tailor your diet to include the RDA but make strive to eat more protein than that.

Protein needed for athletic people

What if you exercise a lot? Jay Hoffman, a professor in the Sport and Exercise Science program at University of Central Florida recommends just 1.4 grams of protein per kilogram of body weight for endurance athletes (Popular Science). The article also notes, “A 2004 study in the journal Nutrition suggests a bit lower, somewhere around 1.1 grams per kilogram, as a minimum required amount, but notes that individual needs may go up to 1.6.”

So does that mean that an athlete should pack away protein powder? Not necessarily. Much of that gets eliminated in urine. Dieticians and nutritionists say the best diet is one that includes protein from a variety of sources besides meat – for instance, nuts, eggs, beans, and dairy.

Finally, there are many good reasons to get more protein into your diet if you aren’t getting the RDA. Protein reduces hunger, curbing the urge to overeat. It helps maintain muscle mass. It’s good for bones and helps older folks maintain healthy and strong bones. Protein also boosts metabolism and reduces cravings. (Source, Healthline.) Just be sure you aren’t neglecting fruits and vegetables, which are also crucial for a healthy diet.