You’re likely familiar with the three macronutrients that fuel your body – carbohydrates, fat, and protein. Of these, protein is the most satiating. In fact, research shows eating a meal high in protein helps curb appetite more than a meal or snack high in fat or carbohydrates. How do we know this?
One study showed that increasing protein intake from 15% of total energy intake to 30% while reducing fat from 35% to 20%, decreased calorie consumption in participants and led to meaningful weight loss. A number of other studies also show that protein can help you stay fuller longer. Your body doesn’t use protein as a primary source of energy but that doesn’t make it any less important. You need protein for a multitude of purposes, one of which is building new muscle tissue You also need protein to make hormones, enzymes, neurotransmitters, antibodies, and more.
Protein has another health benefit. Studies show that diets higher in protein reduce the loss of muscle tissue when you cut back your calorie intake to lose weight. When you lose weight, you shed a combination of fat and lean body tissue. That’s unfortunate since you want to hang onto as much metabolically active muscle tissue as possible. Eating a higher protein diet can help reduce this critical loss of muscle tissue. Plus, a higher protein diet is beneficial if you’re strength training to build muscle size and strength since amino acids are the building blocks for new muscle tissue.
Why does protein help you stay fuller longer? It’s not clear exactly how protein reduces the urge to nibble. However, it doesn’t seem solely due to its impact on appetite hormones like leptin and ghrelin. Exactly why protein is more satiating isn’t completely clear. What IS apparent is that protein evokes greater feelings of fullness. Studies show that satiation is most pronounced when foods are high in protein, fiber, and water. Low on the satiation scale are foods high in fat, refined carbs, and those with added sugar.
Plant-Based vs. Animal Protein
You can get your protein by consuming meat or dairy products, but some plants are also a good source. In fact, plant-based sources of protein are growing in popularity due to concerns about health, animal treatment, and the environment. Does one offer satiety advantages over the other? According to a new study, yes! Plant-based protein may actually keep you fuller longer than protein from animal sources. It makes sense. If protein, fiber, and water are food components that promote longer-term satiety, plants, have all three! If you’ve ever eaten a serving of beans, you know how filling this protein and fiber-rich food is.
In a recent study carried out by University of Copenhagen’s Department of Nutrition, Exercise, and Sports, researchers compared the satiety benefits of plant-based foods to meat. In the study, 43 healthy, young men ate three meals. At each meal, they devoured either a patty made of veal or pork or one composed of peas and beans. Afterward, researchers monitored their calorie intake. The results? After eating the plant-based patty made of beans and peas, the guys ate 12% fewer calories at the next meal relative to their meat-eating peers.
Why the difference? Beans and peas are high in protein but they’re also a significant source of fiber. Research shows that foods that are more satiating are rich in protein, dietary fiber, and have a higher water content. Some fruits and vegetables fall into this category as well.
Other studies also support the satiety benefits of pulses, a term that includes beans, peas, and lentils. One study showed that eating a single serving of pulses a day increased feelings of satiety while another found that eating just one serving each day of plant protein was linked to modest weight loss.
Amino Acid Composition of Plant vs. Animal Foods
Only recently has more focus shifted to plant-based protein as a way to build muscle. Most plant proteins are “incomplete,” meaning the majority of plants don’t contain every essential amino acid your body needs but can’t make. The exceptions are soy foods and quinoa and amaranth, two seeds that are often categorized as whole grains. Even quinoa is relative low in one essential amino acid. However, if you eat a variety of plant-based foods, you will get adequate amounts of each essential amino acid. Assuming you eat a diverse selection of plant proteins, you won’t come up short, even if you avoid animal protein entirely. These days, there are a number of totally plant-based athletes and bodybuilders.
However, you don’t need to be a vegetarian or vegan to enjoy the benefits that plant-based protein offers. By substituting plant-based protein for a portion of the meat you eat, you’ll get more fiber and antioxidants. In fact, beans, nuts, and whole grains, all high in protein, are excellent sources of antioxidants and fiber as well. Plus, research shows nuts reduce c-reactive protein, a marker of low-grade inflammation and are linked with lower mortality.
Other Benefits of Plant-Based Protein
Beyond its satiating power, plant-based protein may protect against cardiovascular disease due to its higher levels of fiber, magnesium, and anti-inflammatory compounds. Plus, a 2016 study found that diets high in whole grains were linked with a reduced mortality from all causes, including cardiovascular disease and cancer. We know that plant-based foods are linked with health benefits and most people in Western countries don’t eat enough of them.
The Bottom Line
A diet that contains a diversity of plant-based proteins may help you stay full while consuming fewer calories. Plus, plants are nutrient dense and have other health benefits that animal foods do not. When you have a hankering for a burger, try a bean or quinoa burger instead! Don’t forget to add some vegetable fixings too.
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