Pea Protein Side Effects

Pea protein is everywhere these days, and for good reason. Like other legumes, peas are a quality source of plant-based protein and rich in other nutrients that can enhance your health.

However, as a supplement, pure pea protein may have different effects than eating whole foods. While most side effects are benign, all protein supplements carry potential risks, especially in high doses.

Protein isn't just for meat eaters. Vegetarians and vegans — and even those who just want to reduce their intake of animal products — have tons of plant-based options, including hemp, soy, rice and pea protein powders. Pea protein is made by isolating the soluble protein in yellow peas. It differs from ground peas in that most of the fiber and starch have been removed.

A 30-gram, two-scoop serving of pure pea protein powder has 27 grams of protein, according to one manufacturer. It's low in carbs, has less than a gram of fat and 120 calories. It's also a good source of iron, with 20 percent of the daily value. Pure pea protein is also free of the top eight most allergenic foods, including milk, eggs, peanuts, tree nuts, soy, fish, shellfish and wheat (although you should always check the label of the supplement you choose.)

From a sustainability perspective, pea protein utilizes fewer resources, including water and fertilizers, and may be better for the environment, according to a review published in the_ Journal of Renal Nutrition_ in September 2017.

Most side effects from pea protein powder are individual and primarily digestive. Whether or not you will experience any digestive upset with pea protein is a matter of trial and error. However, pea protein doesn't have as much risk of digestive upset as whey or casein protein powders. These both contain the milk sugar lactose, to which many people are intolerant or allergic.

Eating a lot of peas will probably give you more digestive trouble than pea protein powder. The fiber in plant foods, especially in large doses, causes bloating, gas and either constipation or diarrhea for many people. However, most of the fiber has been removed from pea protein powder, which is what makes it such a concentrated source of protein.

Just for reference, according to the USDA, to get 27 grams of protein from whole peas, you would need to eat 3.5 cups of whole peas, which would also give you 29 grams of fiber — a lot to stomach in one sitting.

People with reduced kidney function or those susceptible to gout may want to speak with a doctor before choosing pea protein. Pea protein is a rich source of purines, which are substances in both animal and plant foods that the body converts to uric acid.

While purines aren't bad in normal amounts, excess doses could make it difficult for your kidneys to get rid of all the uric acid. This increases the risk of gout, an inflammatory condition in which uric acid builds up in the blood, creating needle-like crystals in the joints that cause episodes of severe, sudden pain and tenderness.

Read more: 7 Popular Protein Myths Totally Busted by Science

Pea protein dangers are the same as those with all protein powders. Because pea protein powder is considered a supplement, it's not regulated by the FDA. This means that supplements can vary widely in quality and purity. According to Harvard Health Publishing, it's not possible to know for sure whether a supplement contains what manufacturers claim.

This unregulated nature of the supplement industry creates the risk that protein powders may potentially contain toxic substances, such as lead, arsenic and cadmium. In 2018, the Clean Label Project tested 134 protein powder products for more than 130 toxins and found that plant-based products were the worst sources, with 75 percent of the products testing positive for lead. This likely has to do with the soil in which the plants are grown, in addition to poor manufacturing processes.

If pure pea protein does cause you digestive problems, look for _hydrolyzed pea protei_n. Hydrolysis breaks down amino acid chains into smaller fragments, which can improve digestibility.

In addition, according to a review article published in August 2012 in the British Journal of Nutrition, hydrolyzed pea protein may be more bioactive, including angiotensin I-converting enzyme inhibitor (ACE) activity and antioxidant activity. ACE inhibitors help relax blood vessels and lower blood pressure, and antioxidants fight free radicals that can damage cells and cause disease.

If you're increasing your protein intake for weight loss, pea protein before a meal may help you reduce your overall calorie intake. In another study published in the British Journal of Nutrition in August 2012, researchers gave healthy male participants either 10 or 20 grams of isolated yellow pea protein either 30 or 120 minutes before a pizza meal.

Consuming 20 grams of pea protein 30 minutes before the meal appeared to have the best results, resulting in a lower cumulative food intake (pea protein supplement plus pizza) compared to the other participants, which included a control group that consumed no pea protein. Twenty grams of pea protein 30 minutes before a meal also lowered pre-meal and post-meal blood sugar levels.

Read more: 20 Fat-Loss Secrets

Finally, compared to other plant-based protein options, pea protein may beat out the competitors in terms of its amino acid profile. Amino acids are the building blocks of protein. There are 20 in total, according to MedlinePlus, 11 of which your body can make, and nine more — called essential amino acids — that you must get from food.

Most plant foods are called incomplete proteins, because they are low in or missing one or more of the amino acids. According to Karen Collins, a registered dietitian and nutrition advisor for the American Institute for Cancer Research, pea protein has a better balance of amino acids compared to protein isolates from hemp, rice and other grains.

People bump up their protein intake for many reasons — chief among those are weight loss and muscle building. Getting adequate protein has been shown to play a crucial role in achieving success in both those pursuits. The dietary reference intake (DRI) for protein established by the Food and Nutrition Board of the National Academies of Medicine is 46 grams daily for women and 56 grams daily for men. This recommendation is based on .8 grams of protein per kilogram of body weight.

However, that amount may not meet the needs of active people and those who want to shed pounds. According to the International Society of Sports Nutrition's position stand on protein and exercise, healthy exercising individuals benefit from getting 1.4 to 2 grams of protein per kilogram of body weight to support exercise recovery and muscle growth. The more intense the exercise, the more protein is required.

For weight loss, extra protein can improve satiety and reduce overall calorie intake, while preserving lean muscle mass. In a study published in Obesity Facts in June 2017, overweight adults who consumed a high-protein diet including 1.34 grams of protein per kilogram of body weight lost more weight than participants who consumed the standard DRI of .8 grams per kilogram, during a six-month trial.

However, getting too much protein won't have any added benefit, and most people can meet their protein needs through a balanced diet. Relying on protein supplements can lead to nutrient deficiencies, since whole foods are much richer sources of naturally occurring vitamins, minerals and antioxidant phytonutrients. If you choose to include pea protein in your diet, make sure it's in moderation and in addition to a healthy, balanced diet.