Plant vs. Animal Protein: Which Is Healthier?

The protein sources you select can impact your long-term health, so it’s important to choose wisely, says Lisa Moskovitz, RD, the CEO of the NY Nutrition Group. But when it comes to weighing the merits of plant versus animal protein, there’s a lot of nuance to consider.

The medical community has encouraged a focus on plant-based protein in recent years, and with good reason.

Heart Health

A study published in the American Journal of Clinical Nutrition in 2024 analyzed 30 years of data on diet, lifestyle, and heart health in more than 200,000 men and women. The analysis revealed that, compared with people whose diets had the lowest ratio of plant to animal protein, those whose diets had the highest ratio were 19 percent less likely to develop cardiovascular disease and 27 percent less likely to experience coronary artery disease.

“Nutrition from plant protein sourced from plant-based diets is typically of higher quality than an omnivorous diet,” says Colin Zhu, DO, a physician and trained chef who has served on the board of the American College of Lifestyle Medicine. “When intentionally planned, a whole foods, plant-based diet provides sufficient nutrient intakes for all stages of life and can be therapeutic for chronic disease, overall health, and healing.”

Gut Health

Plant-based protein sources are often high in fiber, which can improve gastrointestinal function as well as reduce LDL cholesterol levels and overall cardiometabolic health, says Stephani Johnson, RDN, an adjunct professor in the department of clinical and preventive nutrition sciences at Rutgers University in New Brunswick, New Jersey.

“It is important to note that this refers to unprocessed or minimally processed plant-based protein foods — legumes, nuts, and soy — rather than highly processed meat alternatives,” she notes.

Other Benefits

Plant proteins offer antioxidants and “a wide range of minerals that most animal proteins lack,” says Kacie Vavrek, RDN, a dietitian at the Ohio State University Wexner Medical Center in Columbus. “These nutrients support heart health, improve gut health, help regulate blood sugar, and reduce inflammation,” she says.

“Just because plant proteins are advantageous doesn’t mean animal proteins aren’t also,” Moskovitz says.

Muscle Maintenance

Most animal proteins are “complete” proteins, which means they contain all nine essential amino acids required by the body to support normal metabolic function. The majority of plant-based proteins are “incomplete” because they lack one or more of the nine essential acids. (Soy products like tofu, tempeh, edamame, and miso are notable exceptions.)

That doesn’t mean plants are not good sources of protein, Moskovitz says. She just suggests pairing them with animal proteins in your diet.

Because animal proteins are complete proteins, they may have a slight advantage over many forms of plant-based protein in maintaining muscle mass. “Animal proteins [are] a reliable source of high-quality protein, especially for supporting muscle maintenance and recovery,” Vavrek says.

Iron and Vitamins

“Animal proteins tend to be higher in absorbable heme iron and B vitamins,” says Moskovitz.

Heme iron found in meat is more readily absorbable than non-heme iron, Dr. Zhu explains.

Satiety 

Animal proteins have more caloric density than plant-based proteins, which means they may be more effective at satisfying hunger.

The protein provided by animal-based sources can be substantial. “Consuming balanced meals with adequate protein slows gastric emptying compared with high-carbohydrate meals,” Johnson says, adding that this can help you feel full, which can curb cravings and snacking and help you stick with a healthy diet plan.

Certain forms of animal protein pose more significant health risks than plant-based proteins.

Heart Disease Risk

“Not all animal proteins are created equally. Some come with more saturated fat, which drives up ‘bad’ LDL cholesterol and thus, heart disease risk,” Moskovitz says.

Cancer Risk

Plant proteins do not seem to carry the same cancer risks seen with some processed meats. “Processed meats have been clearly linked to higher risk of colorectal and other cancers, largely due to preservatives like nitrites, heme iron, and compounds formed during processing and high-heat cooking,” Vavrek says.

Environmental Risk

The production of animal proteins can tax the environment more than that of plant-based proteins. “They emit more greenhouse gases into the air,” Moskovitz says. “They can also use up more natural resources — but plants may, too.”

Dietitians stress that there’s no need to choose one form of protein over another. Instead, it's important to strike a balance.

But there are a lot of factors that influence the right balance for each person. “There is no ideal per se,” Zhu says.

Johnson agrees. “Individual needs vary based on factors such as age, health status, and personal goals,” she says. “For omnivorous individuals, a general guideline may be to obtain approximately 50 to 70 percent of protein intake from plant-based sources and 30 to 50 percent from animal-based sources.”

But she says this can be hard to put into practice. “A more practical approach is to include ‘plant-forward’ meals — one to two meals per day — centered on plant-based protein sources, while consuming animal-based proteins in the remaining meals.”

Start with a few simple moves. “Add a half cup of lentils to your chicken and rice dish,” Moskovitz suggests. “Make a homemade chili with beans and ground beef.” She also recommends mixing tofu into scrambled eggs and having steak on top of a vegetable-bean salad.

“The key is balance, using animal proteins strategically for nutrient density and protein quality, while relying on plants for fiber and cardioprotective benefits,” Vavrek says.

• There is an ongoing debate over whether plant or animal protein is better.
• While animal proteins may be more satiating, certain types are high in saturated fat; plant proteins have added health benefits such as fiber.
• Ultimately, experts say it’s best to have a mix of both protein sources in your diet.