Updated October 7, 2023

Whether you turn to a vegetarian diet for health or for moral reasons, it is important to know that no diet is perfect. You have to be proactive to make sure you get the right balance of nutrients. What are the consequences — both good and bad — of eating this way? Overall, there are many benefits to choosing a vegetarian diet. Here’s what you need to know.

Healthy Eating Is More than Cutting Out Meat

Children who eat a vegetarian diet grow as well as children who don’t but they tend to have lower weight.

Diagnosis Life summary:
When it comes to growth and development, children who do not eat meat fair just as well as those who do — for the most part. A study in Pediatrics (https://doi.org/10.1542/peds.2021-052598) looked at nearly 9,000 children (596 of them vegetarian) and checked their growth parameters based on their diet. The study spanned at least three years per child. Overall, height and basic laboratory assessments were comparable between the groups, but kids on a vegetarian diet were twice as likely to be underweight. Being underweight could be a sign of malnourishment. It is important to monitor a child’s weight to make sure they are getting adequate nutrition, no matter what diet they’re on.

Eating more fruits and veggies for 8 weeks may help your heart.

Diagnosis Life summary:
Do you eat the recommended 5 to 9 daily servings of fruits and veggies every day? A study in the Annals of Internal Medicine (https://doi.org/10.7326/M20-0336) looked at the effects on blood work when people without heart disease ate one of three diets: 1) a diet rich in fruits and veggies, 2) the DASH diet (low-fat dairy, fish, poultry, fruits, nuts, and veggies), and 3) an “American” diet as a control. The blood work included cardiac biomarkers like troponin, N-terminal pro-B-type natriuretic peptide (BNP), and high-sensitivity C-reactive protein that elevate when there is stress or damage to the heart. After 8 weeks, the fruit and veggie diet and the DASH diet decreased troponin and BNP levels. While that may not necessarily mean that you will be protected against heart disease in the future, the data suggests it could be good for your heart. Do what you can to eat a healthy and balanced diet rich in fruits and veggies.

Five servings is the magic number for fruits and vegetables.

Diagnosis Life summary:
The USDA has recommended 5 to 13 servings of fruits and veggies per day. Is that too much? A study in Circulation (https://doi.org/10.1161/CIRCULATIONAHA.120.048996) looked at the dietary intake of more than 108,000 adults from the Nurses’ Health Study and Health Professionals Follow-Up Study and the Health Professionals Follow-up Study. Over 30 years, 33,898 deaths occurred. Overall, fruits and vegetables — with the exception of fruit juice, potatoes, and starchy vegetables like corn and peas — decreased early mortality. Specifically, 5 servings per day (preferably 2 servings of fruit and 3 servings of veggies) showed the most benefit, at least when compared to only 2 servings. Mortality risk decreased by 13% overall — by 35% when mortality was caused by respiratory disease, by 12% for heart disease, and by 10% for cancer. Eating more than 5 servings per day did not decrease that risk further. Aim for five to stay alive!

The risk for GI cancers may decrease when men eat a vegetarian diet.

Diagnosis Life summary:
It should not be surprising that what you eat could promote a healthy GI tract. Likewise, it could harm it. A meta-analysis in European Journal of Gastroenterology & Hepatology (https://doi.org/10.1097/MEG.0000000000002643) looked at more than 680,000 people to see if the vegetarian diet protected against cancer. Interestingly, cancers were decreased in the stomach, colon, and rectum but not in the esophagus or small intestine. Men, not women, were more likely to see this trend but it depended where they lived. Risk was noted in North American and Asian but not Europe.

Vegans and vegetarians may be at higher risk for fractures.

Diagnosis Life summary:
It is important to make sure you get all the nutrition you need out of your diet. A study in BMC Medicine (https://doi.org/10.1186/s12916-020-01815-3) looked at the risk for bone fractures based on someone’s diet of choice. Specifically, researchers looked at meat-eaters (n=29,380), pescatarians (n=8,037), vegetarians (15,499), and vegans (n=1,982) over nearly 18 years of follow-up. Over that time, there were nearly 4,000 fractures. Non-meat eaters were at higher risk for fractures compared to meat eaters, especially when it came to hip fractures. Vegans had the highest risk of all. This finding persisted even when the data was adjusted for BMI. The risk may relate to lower intakes of calcium and protein in these groups. Pick the diet you feel is best for you, but be sure to supplement what you don’t naturally get in your diet to make sure you don’t face medical problems down the road.

A vegetarian diet is as heart healthy as a Mediterranean diet.

Diagnosis Life summary:
The Mediterranean diet is often toted as being the best diet for heart health. Are there other diets that could be just as effective in decreasing your risk? A study in Circulation (https://doi.org/10/1161/CIRCULATIONAHA.117.030088) compares a low-calorie vegetarian diet with the same calorie Mediterranean diet over 3 months. Both groups lost the same amount of weight. The main difference was in how each diet affected risk factors for heart disease. The vegetarian diet led to more pronounced decreases in LDL (“bad”) cholesterol while Mediterranean diet led to larger decreases in triglycerides. Both diets are, in different ways, heart healthy.

A vegetarian diet may decrease your risk for heart disease but increase your risk for stroke.

Diagnosis Life summary:
People assume a vegetarian diet must be healthy, but like any diet, there are pros and cons. A study in BMJ (https://doi.org/10.1136/bmj.l4897) looked at the diets of more than 48,000 adults who did not have a history for heart disease or stroke beforehand. The researchers divided participants into 3 categories: meat eaters (they ate meat with or without fish), pescatarians (they ate fish but not meat), and vegetarians (they ate no meat or fish). The researchers monitored for new heart attacks and strokes over 18 years. Pescatarians and vegetarians had a 13% lower risk for heart attacks than meat eaters during that time. However, vegetarians but not pescatarians had a 20% higher risk for stroke when compared to meat eaters. It is an interesting correlation but keep in mind, it is only one study. In the interim, the pescatarian diet sounds appealing, not unlike the Mediterranean diet.