Protein is everywhere these days — it’s a trending topic on social media, a common discussion point among friends, and a staple on product ingredient labels in grocery stores. With so much attention on this macronutrient, there’s bound to be conflicting advice around it, as well as myths or misconceptions about it that reach far and wide.
As a dietitian, I often help people determine fact from fiction when it comes to nutrition information. Here, I clear the air on some common protein misinformation I hear, provide the facts, and offer practical nutrition advice.
Myth No. 1: High-protein diets cause kidney damage.
Fact: Unless someone has a pre-existing kidney condition, a high-protein diet is not shown to directly cause kidney damage in healthy individuals.
Our kidneys play a role in protein metabolism, and filtering dietary protein byproducts is just one of the many functions the kidneys are designed to handle. Although glomerular filtration rate (GFR) — a lab value to monitor kidney activity — increases with a higher-protein diet, this is expected and does not indicate internal damage.
However, protein recommendations are not one-size-fits all, and those with compromised kidney function should seek personalized guidance from their medical provider.
Myth No. 2: Your body can only absorb 30 grams of protein at a time.
Fact: Older research proposed that when meals exceeded 25 grams of protein, it no longer supported muscle protein synthesis. However, newer research shows that protein servings up to 100 grams can be fully digested and absorbed in our body, while still largely contributing to muscle protein synthesis after training sessions.
After digestion, our muscles either take up the amino acids from the protein and use them for muscle protein synthesis (muscle building) or the amino acids get shuttled to other tissues for alternative metabolic processes.
In real-world applications, this can provide confidence to those who opt for fewer higher protein meals throughout the day.
From an overall health and recovery standpoint, though, consuming close to 100 grams of protein at once and going long periods between meals can compromise muscle protein synthesis since you may not be getting enough nutrients overall throughout the day. Instead, anchoring each meal with at least 30 grams of high-quality protein can support satiety, lean muscle mass, and blood-sugar regulation; reduce muscle soreness; and promote a healthier metabolic rate.
Rest assured, all protein consumed is digested in the body. Whether you choose to spread your intake throughout the day or eat more concentrated meals depends on your specific nutrient needs and goals.
Myth No. 3: Protein needs decrease with age.
Fact: As we get older, muscle-protein breakdown increases, which can lead to sarcopenia. This means our bodies require more protein just to maintain muscle compared to when we were younger. At the same time, we may not have much of an appetite — for protein or anything else — as hunger signaling tends to decrease with age, too. This is why intentional nutrition is important.
A good rule of thumb for all of us is to aim for at least one gram of protein for every pound of ideal body weight; older individuals can benefit from even more to preserve skeletal muscle, strength, and coordination while reducing risk of injury.
One achievable way to combat low hunger while still consuming high-quality, sufficient protein is the integration of complete protein powders (like LTH Fuel Vegan+All-In-One or LTH Build Whey+All-In-One). These offer a complete serving of 30 grams of protein while also delivering added vitamins, minerals, fiber, probiotics, and digestive enzymes to help you fuel quickly, feel satisfied, and recover well.
Myth No. 4: Overeating protein causes weight gain.
Fact: Rarely is a single nutrient in the diet the sole source of weight gain; weight is incredibly complex and typically the result of a variety of factors beyond nutrition.
When it comes to eating “too much” protein, in particular, the reality is this is challenging because of the natural satiety cues that our bodies signal when we’re eating a high-protein diet. Protein is not a macronutrient to fear: Consuming sufficient protein supports many aspects of our health, including muscle growth, bone health, blood-sugar management, stress resilience, immune support, and detoxification.
That being said, protein does support an increase in lean muscle mass, and since muscle weighs more than body fat, an increase in muscle could cause weight gain. However, an increase in muscle mass indicates improved health and resilience rather than the alternative.
Myth No. 5: All protein sources have equal benefits.
Fact: It’s important to prioritize complete proteins that offer a full profile of the amino acids required by the body. But not all proteins are complete.
Whole grains, beans, nuts and seeds, for example, are incomplete protein sources, meaning they do not contain the optimal number of amino acids your body needs. Relying primarily on them can lead to an amino acid deficiency, resulting in inadequate nutrient status and suboptimal health outcomes. That why it’s essential to prioritize protein-rich foods that offer a full profile of all the essential amino acids, including high-quality meats, fish, shellfish, dairy, and eggs.
Another way to support sufficient high-quality protein intake is to supplement with protein powder, specifically whey protein, as it provides a complete amino acid profile. (If you’re looking for a high-quality whey protein, I recommend the LTH BUILD Whey+All-In-One, LTH Whey Protein, and LTH FLEX Whey Protein Isolate. The LTH Fuel Vegan+All-In-One is also a complete protein supplement as it contains a high enough concentration of amino acids that specifically promote muscle building, unlike other vegan proteins on the market.)
Additionally, supplementing with collagen peptides can also provide protein. Although it’s not a complete protein on its own, research shows that up to one third of your daily intake of protein can come from collagen and still support lean body mass. This is because collagen peptides act as a scaffolding for the body to promote joint resilience as well as hair, skin, and nail health.
As the importance of protein consumption continues to gain traction in the mainstream, many ultra-processed protein products are rising in popularity. While preventing protein deficiency is paramount, prioritizing the consumption of high-quality proteins from well-sourced meat, fish, and intentionally formulated protein powders with a complete amino acid profile is crucial for overall health. Shopping mindfully and intentionally for quality protein sources is just as important as the quantity consumed.
Myth No. 6: High-protein diets cause constipation.
Fact: Whether they mean to or not, people who increase their protein intake often end up replacing fibrous foods in their diet with the macronutrient, which can lead to a low-fiber diet. This, in turn, can result in gut motility issues like constipation.
That’s why it’s essential to consume protein, as well as plenty of high-fiber foods and proper fluids. Both support the breakdown and movement of all these nutrients, which is critical for good gut motility.
If you’re getting adequate fiber and hydration and still having issues, consider the support of a digestive enzyme like LTH Digestive Enzyme Complex.
