When you think about protein in your diet, you're most likely to think of meat. But plant sources of protein are becoming more popular, with 28% of Americans eating more plant protein in 2020 compared to 2019.
Eating less meat and more vegetables has many health benefits. Plant protein may help lower your risk of kidney disease.
Function of kidneys
Your kidneys have the important job of filtering waste products and extra water from your blood. They also remove acids produced in your body, and keep your body’s pH in balance.
Each day, your kidneys filter about 150 quarts of blood. Most of the water and substances are returned to your body.
Your kidneys also help:
Importance of proteins
- Produce hormones
- Build muscle
- Blood clotting
- Repair your cells
Proteins are made of amino acids. There are 20 amino acids, but your body can’t make nine of them. These amino acids must come from foods you eat.
An average person needs about 60 grams of protein per day. This is about 10% to 15% of your daily total calories.
What are plant proteins?
Plant proteins are proteins that come from plant sources. These include legumes, nuts, seeds, vegetables, and soy.
Animal proteins are a complete protein source. They provide all the amino acids you need. But plant proteins lack one or more of these essential amino acids. For example, legumes are low in amino acids cysteine and methionine. Grains are low in lysine.
When you eat plant protein, combine a variety of different plant sources so that you get all the amino acids your body needs.
Your kidneys and protein
Your kidneys remove the waste products that your body makes when breaking down protein. If you have more protein waste, your kidneys need to work harder to remove them. This may stress your kidneys.
If you have too much protein waste, it can build up in your blood. This causes:
- Loss of appetite
- Changes in taste
Eating more plant protein may help take some stress off your kidneys. A study found that healthy people on vegetarian diets have significantly lower levels of creatinine than people who eat both meat and vegetables. Creatinine is a waste product that your muscles make.
On the other hand, eating too much red meat may be bad for your kidneys. A 15-year study of 63,257 adults found that eating more red meat is linked to a higher risk for kidney failure (end-stage renal disease). Those who ate the most red meat also ate the least fruits and vegetables.
Plant protein and kidney health
Some studies have found that replacing some of the animal protein in your diet with plant protein may lower your risk of kidney problems.
A study of 4,881 people in Iran found that when one serving of red and processed meat was replaced with one serving of nuts, legumes, low-fat dairy, and whole grains, there was a lower risk of chronic kidney disease.
Researchers looked at data from 1,065 people with chronic kidney disease in the National Health and Nutrition Examination Survey III. They found that for people with chronic kidney disease, with every 33% increase in plant protein intake, there’s a 23% lower risk of death.
Experts have yet to determine why animal protein may be more toxic to your kidneys than plant protein.
Some researchers say it may be because eating more plant protein can help reduce low-density lipoprotein (LDL) cholesterol (“bad” cholesterol) and uric acid. Plant sources of protein are also rich in nutrients like magnesium, potassium, and calcium. These nutrients may help improve your kidney function. More research is needed to learn how plant protein benefits kidney health.
Sources of plant protein
You don’t need to be a vegetarian to eat plant protein. You can start by substituting some animal protein with plant-based protein. Eat a variety of plant proteins so that you get all your amino acids. Good sources of plant protein include:
- Beans and legumes
- Whole grains like barley, quinoa, and oats
- Seeds and nuts, especially sunflower seeds and peanuts
- Soy products, such as tofu, tempeh, and edamame
It’s important to make the right choices when planning a plant-based diet. Some plant-based foods are made up of processed ingredients like white flour or refined sugar which have some nutrients removed.
When adding more plant protein to your diet, try to:
- Avoid highly processed ingredients, like added sugars and refined grains.
- Eat more minimally-processed plant-based ingredients, like whole grains, legumes, fruits, and vegetables
Health Solutions From Our Sponsors
American Journal of Kidney Diseases: “The Associations of Plant Protein Intake With All-Cause Mortality in CKD.”
BMC Nephrology: “A prospective study on total protein, plant protein and animal protein in relation to the risk of incident chronic kidney disease.”
Journal of the American Society of Nephrology: “Is Dietary Red Meat Kidney Toxic?”
Journal of Renal Nutrition: “A Prospective Study of Dietary Meat Intake and Risk of Incident Chronic Kidney Disease.”
Merck Manual: “Carbohydrates, Proteins, and Fats.”
National Institute of Diabetes and Digestive and Kidney Diseases: “Your Kidneys & How They Work.”
National Kidney Foundation: “CKD Diet: How much protein is the right amount?”
Nutrients: “??Plant Proteins: Assessing Their Nutritional Quality and Effects on Health and Physical Function.”
SUNY Downstate Health Sciences University: “Committee on Plant-Based Health & Nutrition.”
UCLA Health: “Is plant-based protein for you? Here’s what you need to know.”