Researchers reviewed 66 scientific studies to see if eating more plant-based proteins could help people with common digestive diseases like fatty liver disease, acid reflux, and irritable bowel syndrome. These conditions are often made worse by poor eating habits. The review found that plant-based proteins may help improve these conditions, but scientists still need to learn more about the best ways to use them and whether they’re safe for everyone. The findings suggest plant-based proteins could be an important tool for helping people manage their digestive health through better nutrition.

The Quick Take

  • What they studied: Whether eating foods made from plant proteins (like beans, lentils, soy, and nuts) could help people with digestive diseases that are caused or made worse by poor diet
  • Who participated: This was a review of 66 published research studies about plant-based proteins and digestive health. The review didn’t involve new patients, but looked at what other scientists had already discovered
  • Key finding: Plant-based proteins appear to help with three common digestive problems: fatty liver disease, acid reflux (heartburn), and irritable bowel syndrome. However, more research is needed to know exactly how much to eat and who benefits most
  • What it means for you: If you have digestive problems related to diet, adding more plant-based proteins to your meals may help. However, talk to your doctor before making major diet changes, especially if you take medications or have other health conditions

The Research Details

Scientists searched five major medical databases for all published studies about plant-based proteins and digestive diseases. They started with 314 studies but carefully reviewed each one to make sure it was relevant and high-quality. After removing duplicate studies and those that didn’t fit their criteria, they analyzed 66 studies in detail.

This type of research is called a ‘review’ or ’literature review.’ Instead of doing a new experiment with patients, reviewers read through existing research and summarize what scientists have already learned. This helps doctors and patients understand what the current evidence shows about a topic.

The researchers looked specifically at three digestive diseases: metabolically associated fatty liver disease (when fat builds up in the liver), gastroesophageal reflux disease (acid reflux or heartburn), and irritable bowel syndrome (a condition that causes stomach pain and changes in bowel habits).

This research approach is important because it brings together all the available evidence in one place. Instead of looking at one small study, doctors and patients can see the bigger picture of what science shows. This helps identify patterns and trends that might not be obvious from single studies. The researchers also looked at whether plant-based protein diets are nutritionally complete and safe, which is practical information people need before changing their diet.

This is a review of existing research, which means it depends on the quality of the studies it includes. The researchers used established medical databases and clear criteria for choosing studies, which makes their work more reliable. However, because they reviewed studies rather than conducting a new experiment, the strength of their conclusions depends on how good those original studies were. The fact that they reviewed 66 studies from multiple databases suggests they did a thorough job, but readers should know that reviews can sometimes reach different conclusions than the original studies if they’re not careful about which studies they include.

What the Results Show

The review found that plant-based proteins may help people with three common digestive diseases. For fatty liver disease, plant-based proteins appear to reduce fat buildup in the liver and improve how the liver works. For acid reflux, these proteins seem to reduce symptoms like heartburn and throat irritation. For irritable bowel syndrome, plant-based proteins may help reduce pain, bloating, and irregular bowel movements.

The researchers noted that plant-based proteins work differently than animal proteins in the body. They contain fiber, special plant compounds, and different types of fats that may be gentler on the digestive system. These proteins also help feed the good bacteria in your gut, which plays an important role in digestive health.

The review also examined whether diets based on plant proteins provide all the nutrients your body needs. The researchers found that well-planned plant-based protein diets can be nutritionally complete if they include a variety of foods like beans, lentils, nuts, seeds, and whole grains. However, people need to make sure they’re getting enough vitamin B12, iron, and other nutrients that are easier to get from animal products.

The researchers also looked at potential side effects and safety concerns. Some people may experience bloating or gas when they first increase plant-based proteins because of the fiber content. However, these symptoms usually go away as the body adjusts. The review found that plant-based protein diets are generally safe for most people, including those with digestive diseases. The researchers also discussed the economic and practical benefits of plant-based proteins—they’re often cheaper than animal proteins and more environmentally friendly to produce.

This review builds on previous research showing that diet plays an important role in digestive health. Earlier studies showed that animal-based diets high in processed foods can worsen digestive diseases. This review adds to that knowledge by specifically examining whether plant-based proteins offer benefits. The findings support what some earlier studies suggested but provide a more complete picture by looking at multiple diseases and considering practical factors like nutrition and safety.

This review has several important limitations. First, it depends on the quality of the 66 studies it reviewed—if those studies had problems, the review’s conclusions may not be completely accurate. Second, many of the original studies were small or done in specific countries, so the results might not apply to everyone. Third, the review didn’t find enough information about the best amount of plant-based protein to eat or which specific plant proteins work best for each disease. Finally, more research is needed to understand exactly how plant-based proteins help digestive health and whether they work equally well for all people.

The Bottom Line

If you have a digestive disease related to diet (like fatty liver disease, acid reflux, or irritable bowel syndrome), consider adding more plant-based proteins to your meals. This could mean eating more beans, lentils, tofu, nuts, and seeds. Start slowly to let your digestive system adjust. Make sure your diet includes a variety of plant-based foods to get all the nutrients you need. However, these findings are based on existing research and should not replace medical advice—talk to your doctor or a dietitian before making major diet changes, especially if you take medications.

This research is most relevant for people with digestive diseases caused or worsened by diet, including those with fatty liver disease, acid reflux, or irritable bowel syndrome. It may also interest people looking to improve their digestive health through better nutrition. However, people with certain conditions (like kidney disease or severe protein allergies) should talk to their doctor before significantly changing their protein sources. Vegetarians and vegans may find this research particularly useful for understanding how to optimize their diets for digestive health.

You may notice improvements in digestive symptoms within a few weeks of adding more plant-based proteins, though some people take longer. Fatty liver disease typically takes several months to improve with dietary changes. It’s important to be patient and consistent—dietary changes work best when you stick with them over time. If you don’t see improvement after 4-6 weeks, talk to your doctor about other options.

Want to Apply This Research?

  • Track your daily plant-based protein intake (in grams) and rate your digestive symptoms (bloating, pain, reflux) on a scale of 1-10 each day. This helps you see if increasing plant proteins correlates with symptom improvement
  • Set a goal to include one plant-based protein source at each meal (beans at lunch, nuts as a snack, lentils at dinner). Start with small portions and gradually increase to let your digestive system adjust
  • Weekly check-in: Review your symptom ratings and plant-based protein intake. If symptoms improve, maintain your current intake. If symptoms worsen or don’t improve after 4-6 weeks, adjust portions or try different plant proteins, and consult your healthcare provider

This review summarizes existing research about plant-based proteins and digestive health but is not a substitute for professional medical advice. If you have a digestive disease or are considering major dietary changes, consult your doctor or registered dietitian before starting. This is especially important if you take medications, have allergies, or have other health conditions. The findings in this review suggest plant-based proteins may help, but individual results vary, and more research is needed to determine the best approach for each person.