Myth #1: More protein = more muscle
It's a fact that your body can't properly repair or generate muscle without the full suite of essential amino acids found in food sources of protein. But just eating protein isn't enough to build or maintain strength and muscle mass, Baum says.
"You need exercise to do that," she explains. Especially as you age, and muscle loss or "wasting" put you at risk for mobility issues and serious falls, both aerobic and resistance exercise are necessary to help your body hold onto and build muscle, says nutrition expert Dr Wayne Campbell.
Myth #2: All protein is created equal
Pretty much everything you put in your mouth (apart from water) contains at least a little protein. But not all food sources of protein contain the essential amino acids your body requires to support muscle and cell health, Baum says.
"There's a huge difference between animal and plant sources of protein," she explains. "While animal foods" - meat, dairy, eggs, fish - "are complete sources of essential amino acids, plants are not." Also, not all the protein packed into plants is bioavailable, she says. "The fibre in some plant-sources of protein may prevent the digestion and absorption of some amino acids," she explains.
That said, you don't need animals in your diet to get the protein amino acids your body needs. But if you're eating a diet largely free of animal products, you need to put a little more thought into your menus, Baum says.
Try to combine legumes like beans, lentils, and peanuts with whole grains. Together, legumes and whole grains provide all the essential amino acids you require, says dietitian Dr Winston Craig.
Myth #3: The more protein you eat, the better
The average person eats roughly 80 to 90 grams of protein a day - roughly twice the daily amount recommended, says nutrition and metabolism expert Dr Douglas Paddon-Jones.
"If you're eating an omnivorous diet" - that is, a diet that includes both plants and animals - "protein inadequacy is really not an issue," Paddon-Jones says. Also, in terms of both building muscle and satisfying hunger, "there's a limit to how much protein your body can actually use," he explains. For most people, that limit is somewhere between 25 and 30 grams per meal, he says. That's roughly the amount in two eggs or a 90g portion of meat.
Instead of trying to pack more protein into your diet, Paddon-Jones says most of us should look to redistribute the protein we're already getting. He points out that many of us eat little to no protein with breakfast and a heaping helping with dinner.
Rather than a big slab of beef with beans, rice, and other plant sources of protein in the evening, he recommends reducing your protein portions at night and adding some of that meat or veggie protein to your breakfast.
Myth #4: You need protein right after a workout
Don't feel like you need to slam a super sized protein shake after every gym visit in order to maximise your workout gains. "People in Arnold Schwarzenegger-type bodybuilding competitions probably need protein every four hours," Baum says. But for the rest of us, eating protein with our meals will provide our muscles with everything they need to take advantage of exercise, she says.
Research backs her up. A recent study on "protein timing" in the Journal of the International Society of Sports Nutrition found that downing the stuff right after a workout had no beneficial effects on muscle growth or strength compared to eating the same amount of protein later on with meals.
Myth #5: If you're tired, you probably haven't eaten enough protein
Feeling wiped out all the time could be a sign that you body's running low on protein. But this is only going to occur if your protein stores are super depleted - we're talking very severe protein shortages, not cutting out protein for a meal or two, Campbell says.
If you're vegan (or otherwise avoiding animal sources of protein), AND you're wiped out all day, AND your limbs seem to be getting skinnier even though your gut and waist size aren't changing, then it's possible you may not be consuming enough protein, Campbell says. (Talk with a dietitian.) But in most cases, if you're feeling tired it probably has nothing to do with your protein intake, he says.
Myth #6: Eating more protein keeps your weight down
Baum says protein can increase "satiety" - or feelings of sustained fullness following a meal. But there's a limit to this effect. "You can still overdo it and eat too much protein, and it can still make you fat," she says.
If you're looking to add protein foods to your diet in order to knock down hunger and support muscle health, she recommends swapping carb kilojoules for protein kilojoules - as opposed to simply adding protein to whatever you're currently eating.
One example: If you usually eat a whole-wheat bagel with cream cheese for breakfast, don't just add eggs or Greek yoghurt to your plate. Instead, reduce your bagel portion to make room for those eggs or yoghurt.