When you go plant-based the number question everyone asks you is, "Where do you get your protein?" It might surprise you to learn that plant foods are full of protein, from the mighty soybean ( 28 grams per cup) to the tiny pea (8 grams per cup). The list goes on and includes all nature of legumes: Lentils (18 grams per cup), peas (16 grams per cup), chickpeas (11 grams per cup), as well as greens like artichokes (4.5 grams per cup) and many more vegetables (like broccoli, with nearly 4 grams per cup). The amount of protein in pistachios might surprise you: Just 1/4 cup of our favorite snack provides 6 grams of protein!

Still, those who want to make the shift to plant-based protein persistently get pushback from the meat-eaters in their lives, who argue that plant protein can't be as effective in building strong muscles as animal protein. Racehorses build sleek bodies on a diet of grains and hay, and gorillas build mighty mass on a diet of leaves and berries. What the omnivores don't add, but is backed by mounting scientific evidence, is that animal protein comes packaged (figuratively speaking) with damaging saturated fat and other inflammatory compounds that have been shown in study after study to raise your risk of heart disease, diabetes, high blood pressure, some hormonal cancers such as breast and prostate, and chronic disease linked to obesity and being overweight. Plant-eaters are leaner, less heavy, and live longer, the studies show. So if you want to raise your risk of chronic illness, obesity. and cancer or heart disease, choose animal protein; If you want to be healthier, more energetic, and live longer, pick plants.

Study: In aging muscles, it takes less animal protein to maintain size and strength

Now a new study just out, done in the UK, appears to give the meat-eaters a little boost since it found that it took less animal protein to maintain muscle mass in aging bodies. But the simple fix, according to the authors, is that when you switch to a primarily plant-based diet, you need to add more protein to your plate to maintain the same weight. For most people, another helping of chickpeas or edamame is not such a burden.

The study, out of the UK, where there are more vegans per capita than in the US, is relevant to a population that gave up animal product for their health, and now as they age needs to keep their weight on and their strength up. The researchers only measured soy and wheat proteins (yes grains contain protein) and it did not take into effect that the animal protein alternatives come with other harmful health caveats. A multitude of studies have shown that a diet rich in fiber (found only in vegetables, fruits, whole grains, seeds, and nuts), lowers obesity and your lifetime risk of heart disease, type 2 diabetes, high blood pressure, and chronic illnesses brought on by inflammation. Nor did the UK study look at overall BMI, which is lower among those who follow plant-based diets.

"On a gram for gram basis, animal proteins are more effective than plant proteins in supporting the maintenance of skeletal muscle mass with advancing age," the authors wrote. The research was on an elderly population that has the unique problem of keeping their weight on.

The study also concluded that plant-protein works, you simply have to adjust the amount that you eat. The lead author, Oliver Witard, commented: "This research challenges the broad viewpoint that plant proteins don't help build muscles as much as animal protein by highlighting the potential of alternative plant-based protein sources to maintain the size and quality of aging muscles."

"A larger dose of soy and wheat proteins is required to achieve a comparable response of building muscles," the researchers stated. However, further studies are required to measure how other plant-based proteins compare, such as peas, oats, nuts, and other beans.

To reduce heart disease and mortality risk, choose plant proteins for the win

In another new study, this one in Japan, a diet of animal protein was associated with higher mortality rates, and a diet of plant-based protein resulted in more longevity. In their words:

"In this cohort study of 70,696 Japanese adults followed up for a mean of 18 years, higher intake of plant protein was associated with lower total mortality. Moreover, [the] substitution of plant protein for animal protein, mainly for red or processed meat protein, was associated with lower risk of total, cancer-related, and cardiovascular disease-related mortality.

"Meaning:  A higher intake of plant-based proteins may contribute to long-term health and longevity." So if you're looking to live longer, it is becoming abundantly clear that plant-protein wins.

And earlier this month the British Medical Journal published a new study that found a high intake of protein from plants such as legumes, whole grains, and nuts is linked to lower risk of developing diseases such as heart disease, diabetes, and obesity-related hypertension.

 So how do you get enough protein from plant-based foods?

There are 9 essential amino acids that your body needs to get from your diet. Out of 20 amino acids in the world, your body can make 11 of them, but the others require you to provide the building blocks from the food you eat. You can get these from a varied plant-based diet that provides plenty of protein, including tofu, legumes, greens like broccoli, seeds such as hemp, chia, or pumpkins, and nuts like almonds.

To figure out how much protein you need in a day use this easy calculation: The average person requires 0.8 grams of protein per kilogram of body weight or 0.36 grams per pound. As a general rule, women should eat approximately 45 to 55 grams of protein per day, or more if you are super active, whereas men need anywhere from 55 to 75 grams. This daily recommendation depends on your weight and activity level, so if you're training for an event you may want to add more protein to your diet. Check out your best way to calculate your needs is using this handy tool from Calculator.net.

Complete proteins are great but your body can assemble the building blocks

The second thing you need to know is that some foods are "complete proteins" while others provide the building blocks. New research shows you don't need to eat all the aminos at one sitting, since your body can assemble them in the liver and deliver protein to all the parts of the body that need them.

If you want to eat complete proteins at a sitting, they are found in these plant foods:

  • Miso (32 grams per cup)
  • Tempeh (31 grams per cup)
  • Tofu (with 10 grams a cup)
  • Edamame (17 grams per cup)
  • Amaranth (9 grams of protein per cup)
  • Quinoa (8 grams per cup)
  • Buckwheat (with 5.7 grams of protein per cup)
  • Ezekiel bread (4 grams of protein and 3 grams of fiber per slice)

But rather than worry about getting all 9 at once, eat a varied plant-based diet throughout the day and your body can take care of the rest. One easy way is to combine rice and beans, but you can also just make sure to get a variety of plant-based foods and be sure to include legumes like chickpeas in your lunch salad. You don't have to eat all the building blocks at once, as nutritionists once thought since your body has the extraordinary ability to assemble them into the necessary proteins to operate at peak performance.

In a recent study on protein needs and whether vegetarians and vegans get enough, the conclusions show that as long as they eat a varied diet, they get more than enough:

"If a diet has at least a modest amount of variability (which is the case in economically developed countries) there are no issues regarding sufficient intakes of any individual indispensable amino acids from vegetarian diets, including lysine," one of the essential amino acids found in nuts and seeds, the study concluded.

When you look at protein sources, one question is: What else comes in that package?

Casein, the key protein in milk and cheese, has been linked to cancer growth. The respected scientist and author of The China Study, the larget review study of diet and health to date, T. Colin Campbell describes the fact that cancer cells in a lab experiment on mice grew more rapidly and larger when given casein, the protein in milk and dairy. When the mice with the largest tumors were taken off casein and fed plant protein, the cancer cells shrank.

The same type of thing happens in heart patients. Dr. Caldwell Esselstyn, who appears in the documentary Forks Over Knives with T. Colin Campbell, describes that when heart patients at the Cleveland Clinic where he worked were taken off the animal products and switched to plant-based proteins, their clogged arteries and plaque not only slowed but reversed. The body appears to absorb these calcium deposits and heal itself, allowing his patients to come off some of their heart meds, and feel more energetic and healthier than they had in years.

So to answer the question which is better for you, animal protein or plant protein, the answer is clear: Eat a varied plant-based diet for a clean, healthy protein that provides energy and builds lean muscles, and if you work out strenuously, replace your protein within an hour. Unless you want a dose of heart disease or cancer risk with your protein, choose plants. Just add more of it to your plate to build lean muscle and keep your weight in check.

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