It’s a no-brainer that protein helps you stay lean and strong, but maybe you’re unsure exactly just how much you should be getting to reach your current fitness goals. Your gym buff boyfriend recommends one thing, but your nutritionist says another, and that article you just read online tells you something else altogether. We’ve got the real scoop on protein, including why you need it, the best types to choose, and the amount you should consume to look and feel your best.

Building Block Basics

Protein’s main function is to build and repair the body’s tissues, including muscles, plus synthesize hormones and enzymes. Since protein is constantly being broken down, it’s vital to consume this all-important macronutrient at every meal, and especially after strenuous workouts. Protein is made up of two groups of 20 amino acids, including both essential (your body doesn’t make them, so you can get them only from what you eat) and non-essential (your body synthesizes from other compounds such as fats and carbohydrates) aminos. They can be further broken into two classes, complete and incomplete. A complete protein has the full essential amino acid profile in the correct ratios; an incomplete protein lacks one or more essential amino acids.

SEE ALSO: The New Rules of Nutrient Timing

How much protein do I really need?
The RDA suggests 0.83 grams of protein per kilogram of body weight for the average woman (about 53g for a 140-pound woman). But a bodybuilder or active recreational athlete needs a bit more—between 1 and 2 grams per kilogram of body weight, according to the National Academy of Sports Medicine (NASM). For an active woman who weighs 140 pounds, that’s about 64–127 grams daily.

Does it matter when I eat it?
Since your body is always repairing and building tissue, you need to constantly replace your protein stores. Otherwise, you’ll start to break down protein from muscle to make glucose for fuel. Aim to consume 4 to 5 ounces (or 25–30 grams) of protein every 2.5–3.5 hours (about five to six times a day). Great sources include eggs, milk, meat, fish, poultry, cottage cheese, Greek yogurt, quinoa, amaranth, bulgur, tofu, and combinations like beans or lentils and rice (which together make complete proteins). A balanced lunch might be 4 ounces of grilled chicken over salad with a rainbow of fresh vegetables; an energizing afternoon snack might include 6 ounces of Greek yogurt or ¾ cup of low-fat cottage cheese with some nuts and fresh berries.

Is it possible to get too much protein?
Yes. Your body can absorb only about 30 grams of protein (4–5 ounces) at a time, so if you take in more than that, you’ll store the excess as fat.

Following a high-protein diet (one where protein makes up more than 40% of your daily total caloric intake) can also put a strain on the kidneys, which have to work harder to remove the by-products of protein digestion. For every gram of protein consumed above 2 grams per day, about 1–1.5 milligrams of calcium is also excreted, which leads to loss of bone density. Aim for macronutrient ratios of no more than 40% protein, 30–35% carbs, and 25–30% fats.

Can protein help me lose weight?
Yes. Higher-protein foods require more work as your body breaks them down to use for fuel, so you’ll naturally burn more calories to digest them. Plus, high-protein foods help you feel fuller longer, so you’re less likely to snack or overeat. Research published in the American Journal of Clinical Nutrition also shows that higher protein intake (about 30–40% of the diet) helps to boost levels of the hormone leptin (the so-called satiety hormone), while reducing levels of the hunger hormone ghrelin, helping you stay satisfied after meals or snacks.

What if I don’t get enough protein?
Your body uses its own muscle stores for fuel when there’s a lack of protein. That’s especially bad when trying to build lean muscle. To get the gains you want at the gym (and recovering post-workout), consume either complete amino acids (like dairy or meat) or a combination of incomplete (such as rice and beans) at every meal and snack.

Powerhouse Proteins
Our five favorite foods for keeping your muscles strong and your body energized

➜ Lean Grass-fed Beef or Bison
High in iron, omega-3s, vitamin E, and conjugated linoleic acid (CLA) compared with grain-fed cattle; each 4- to 5-ounce portion will yield more than 25 grams of protein.

SEE ALSO: Bison vs. Beef: Which Is Healthier?

➜ Eggs
Rich in vitamin D and choline (from the yolk), the whites contain the most easily absorbable protein source. To cut down on the fat, mix one whole egg with four or five egg whites. One whole egg contains about 7 grams of protein.

➜ Greek Yogurt
Higher in protein (about 17 grams per serving ) and lower in carbs than regular yogurt, the Greek variety is also packed with important probiotics for intestinal health.

➜ Cottage Cheese
The creamy texture makes this dairy standard easy to blend in a salad with balsamic vinegar or to add dimension to omelets. One cup contains an amazing 28 grams of protein. For maximum health benefits, stick to the no-salt added, 1% milk fat variety.

➜ Beans
In addition to being loaded with protein (chickpeas, for example, have 20 grams per half cup), most beans are also rich in fiber. Other high-protein choices include pinto beans (10g per half cup), edamame (8g per half cup), and black beans (7g per half cup).

Essential Powders

We know you can’t always get all the protein you need or want through whole foods alone. When you’re on the go or just in a rush, protein powders are an easy way to ensure you’re getting enough of the nutrient. But quality protein powders can come in many forms, all with their own unique benefits, from how quickly they can be absorbed to the type of aminos they provide. Below, a look at some of the most popular options, and how to use them.

1. Whey
Why use it: Ideal for promoting muscle synthesis, it’s also quickly absorbed (just 20–30 minutes) and delivers amino acids straight to the bloodstream, making it a perfect post-workout recovery drink. Whey is loaded with high levels of branched-chain amino acids (BCAAs), which are responsible for muscle synthesis, and it raises insulin levels to get energy to the muscles quickly for repair.
Try this: Isoflex Whey Protein Isolate from Allmax has 0 grams of sugar or fat but contains 27 grams of fast-absorbing protein per serving. (allmaxnutrition.com)

2. Casein
Why use it: A slower-digesting protein (it can take up to seven hours to break down), casein provides a constant supply of aminos to the muscles for strength and growth. One unique benefit of casein is that it has the highest levels of glutamine of any protein powder. This amino can be depleted when the body is under stress either from a hard workout or an illness. Having a casein shake a night can also help you wake up feeling energized. A great way to achieve maximum benefits is to combine a whey/casein shake right after your workout. A University of Texas Medical Branch study found that trained bodybuilders who consumed whey and casein together gained more lean muscle mass in eight weeks of training than those who consumed only whey.
Try this: Optimum Nutrition (ON) Gold Standard 100% Casein contains 24 grams of anti-catabolic micellar casein per scoop. (optimumnutrition.com)

3. Egg
Why use it: An extremely high-quality protein, it’s also the most easily absorbed by your body. Egg powders contain 40 different types of proteins. Research has shown that it stimulates muscle growth in the same manner as whey and casein.
Try this: GNC Pro Performance 100% Egg Protein is highly digestible, quick-absorbing, lactose-free, and features 25 grams of protein per serving. (gnc.com)

4. Beef
Why use it: For those who are lactose-intolerant, beef is an excellent option, since it contains all of the required amino acids along with creatine and B vitamins. Think of it as lean steak, without the fat and cholesterol.
Try this: MHP’s Paleo Protein Beef and Egg White Protein delivers 20 grams of the nutrient per serving. (mhpstrong.com)

5. Soy
Why use it: Soy has been shown to be as effective in muscle synthesis as whey, plus it also contains many antioxidants. Soy has gotten a bad rap because of its phytoestrogen isoflavones that are similar to the female hormone estrogen (some cite concerns that raising estrogen levels may be linked to certain cancers). Although research is not conclusive, some women might want to use it in moderation.
Try this: Six Star Soy Protein is lactose-, cholesterol-, and sugar-free with a complete spectrum of amino acids. (sixstarpro.com)

6. Brown Rice
Why use it: We tend to think of rice as a carb-heavy option, but when you separate the carbs and protein during the manufacturing process, you’ll get a powder that’s 70% protein. It’s also extremely high in arginine, an amino that aids in recovery and delivers precious nutrients to muscles.
Try this: About Time VE 2lb Natural Vegan Protein features 24 grams of plant-based protein from peas, pumpkins, and brown rice. (tryabouttime.com)

7. Pea
Why use it: Packed with protein, glutamine, and BCAAs, pea protein is also high in arginine (three times the amount found in whey). Arginine stimulates blood flow by dilating blood vessels, allowing nutrients to be delivered to the muscles more quickly for a bigger pump during workouts and faster recovery afterward.
Try this: Now Sports Pea Protein Powder has 24 grams of pure, non-GMO ­vegetable protein per serving. (nowfoods.com)