It’s become nutritional common knowledge that protein is the magic ingredient when it comes to everything from muscle building to beautiful hair and skin.
Naturally, health food marketers have also taken note, packing upwards of 30 grams of protein into a single nutrition bar or a shake wherever possible. (Not to mention adding some serious flexed bicep imagery to the container…)
But just how much of that is your body actually absorbing? And is too much protein bad for you?
We asked two super qualified nutritionists—Foodtrainers founder Lauren Slayton, MS, RD, and Pritikin Longevity Center and Spa nutrition director Kimberly Gomer, MS, RD, LDN—to help us unpack the facts.
Here are five rules to follow for perfecting your protein intake:
1. Base your protein intake on your body. “Age, activity level, and your size will affect your protein needs,” Slayton says. The standard recommendation for daily intake is about 0.8 grams of protein to every kilogram of body weight, which works out to about 47 grams for the average-sized young woman, and both Slayton and Gromer say that hovering around that 50 mark is a good idea. Just be sure to get more if you’re hitting back-to-back Barry’s Bootcamp classes. “I would say 50 grams if you’re not very active, 75 grams if you’re moderately active, and 100 or more to put on muscle,” Slayton says.
For context, two eggs have about 12 grams of protein, lentils have 26 grams of protein in a half cup, and one cup of quinoa has eight grams of protein.
2. Don’t eat more than 30 grams of protein in one meal. You might be tempted to just squeeze as much as possible into every meal, but more isn’t always better. Studies have shown that only the first 30 grams consumed in a meal contribute to building muscle, and going for more could backfire. “Unlike starch or glucose, we have no storage form of protein,” Gromer says. “Once you go beyond the amount that you can absorb in one sitting, it will turn into fat stores.” (Gasp!)
3. Instead, space it out. Protein is slow to absorb, so you while you may feel sluggish if you eat too much at one meal, spreading it out over meals throughout the day will have the opposite effect, says Slayton. “This is the beauty of protein—it takes its time getting assimilated and that’s why protein keeps us more satisfied.”
4. Pick smoothies over protein bars for ease of absorption. Both Gromer and Slayton say whole foods are best, but if you’re looking for a concentrated, on-the-go protein infusion for putting on muscle, they want you to sip a protein smoothie. “Anything that’s dry and processed [like a protein bar] I don’t recommend because they’re too dense on the digestive system,” Gromer says. Instead, whip out your Nutribullet or head to a smoothie bar. “In terms of speed of absorption, protein powder, and specifically whey, is best,” Slayton says. “If you want to put on a little muscle, this is important, and liquids are most rapidly absorbed.”
5. Pay attention to the source. Of course, like all nutrients, you want your protein to be as clean as possible. “People often don’t may enough attention to protein quality. What gives protein a bad rap in the research, in my opinion, is that most of the protein is factory meat, conventional dairy, etc. Is it protein or is it preservatives and antibiotics that’s the problem?” Slayton says. “Quality counts in every food decision.” —Jamie McKillop