Do You Need Protein Powder Supplements? Here’s What Nutritionists Say

You probably know you need protein in your diet, and you likely have an idea of where you can find it. Meat, nuts, and eggs may all come to mind when you think of protein-rich foods, and perhaps you’ve even tried supplements like protein bars or whey protein powders. But do you know what protein is, exactly, and what it does for your body?

Protein is a macronutrient, which means it’s a substance that you need to stay alive, registered dietitian nutritionist Keri Gans, author of The Small Change Diet, tells Allure. “Protein is basically the building block of life; it helps to repair and build tissues and muscle,” she says. Here’s what else you need to know about protein, including how much of it you should be getting a day best whey protein powder.

What does protein do for your body?

Made up of amino acids, it is a building block for your muscles, bones, skin, cartilage, and blood, Alissa Rumsey, a registered dietitian nutritionist and founder of Alissa Rumsey Nutrition & Wellness, tells Allure. According to registered dietitian nutritionist Beth Warren, founder of Beth Warren Nutrition and author of Living a Real Life with Real Food, it helps you build muscle mass, keeps your immune system strong, balances your hormones, and helps give you that full feeling after you eat.

How much protein should I get each day?

Everyone’s protein needs are slightly different, but the Recommended Daily Allowance (RDA) is a minimum of 0.8 grams per kilogram of your body weight, says Sonya Angelone, a registered dietitian nutritionist and spokeswoman for the Academy of Nutrition and Dietetics. Your age, weight, height, whether you’re pregnant or breastfeeding, and how often you exercise also factor in. For example, if you’re an active 30-year-old woman who is 140 pounds and five-foot-six, you’ll need about 51 grams of protein a day, according to the United States Department of Agriculture (USDA). (The USDA has an online calculator that can help you figure out your exact protein needs.) That requirement changes slightly if, for example, you’re breastfeeding (you may need more), you’re sedentary (you may need less), or you weigh more or less.

What happens if you don’t get enough protein?

Given that protein is an essential nutrient, not getting enough can wreak havoc on your body. Protein deficiency may reduce your muscle mass and therefore your metabolism, Warren says, as well as lead to hair loss, skin patches, and difficulty losing weight. Your immune system also might be compromised over time, Gans notes, making you likelier to get sick and more affected when you do.

What happens when you get too much protein?

In the short term, you’ll probably be OK if you consume a little more protein than recommended: As certified dietitian-nutritionist Gina Keatley tells Allure, surplus protein can lead to “an increase in ammonia within the body, but this is easily cleared with a slight increase of water in the healthy adult.” But if you’re on a high-protein diet for a long period of time, you can develop a condition known as hypercalcemia, which causes elevated levels of calcium in your urine, Keatley says. Those higher-than-normal levels of calcium can happen when your body starts to break down your bone and can lead to kidney stones and kidney failure, according to the Mayo Clinic.

Are all forms of protein created equal?

You can get protein from many different sources, per the USDA, including meat such as beef, pork, and poultry; seafood; beans and lentils; eggs; dairy; and soy products, nuts, and seeds. Some nutritionists emphasize the nutritional value of lean meat, since, as Keatley says, “Non-animal sources of protein do not contain all of the amino acids [or proteins] that are necessary for life.” That doesn’t mean they’re bad, per se, they just don’t have all of the range of proteins you’d get if you were to eat animal products.