– Stanford Moore, Nobel Prize-winning Biochemist |
An essential to human life(1), protein is second only to water when it comes to the contents of your body. In fact, your muscles and each cell in your body is made of proteins.
Then why do you need a low protein diet?
As one of the major macronutrients that provide energy (or calories) to the body, protein requires to be broken down by your body so that the singular amino acids (protein building blocks) can carry out vital functions. However, if your body is unable to digest and use certain amino acids, it can place a strain on your organs and create a host of complications.
| Out of the 21 amino acids common to all life forms, our body cannot produce nine. These essential amino acids are obtained by consuming protein-rich food(2). |
An average person must get at least 10% to 15% of its calorie requirements from protein. However, if you suffer from one or more of the following health conditions, you should follow a diet that restricts the amount of protein you consume so that it only constitutes 4% to 8% of your daily calorie intake.
A low-protein diet reduces the pressure that may build on your organs when you’re unable to process amino acids properly.
Kidneys filter the waste from the foods you eat to help maintain the right balance of minerals and nutrients in your blood and body. When your kidneys are not functioning properly, the waste from the protein and urea (the compound released when you consume protein) can build up in the blood and cause fatigue, nausea, loss of appetite, and weakness.
The National Kidney Foundation(3) proclaims that if you have kidney diseases and you’re not on dialysis, reducing your protein intake and consuming more plant-based foods can slow the loss of your kidney functions. However, if you’re on dialysis, a low protein diet for your kidney disease will not be required, since dialysis removes the protein waste from your body.
Diabetes can induce kidney diseases when high glucose levels owing to diabetes damage the parts of the kidneys that filter blood. This damaged filter can then leak urea into your blood, which can further build up and cause several complications. A review(4) of controlled trials has proved that adopting a low protein diet can significantly improve kidney functions in patients of diabetic nephropathy.
A rare genetic birth condition, Phenylketonuria decreases the metabolism of an amino acid called phenylalanine (Phe). It results in increased levels of amino acid in the blood, which your body cannot process.
If the Phe levels become too high, it can lead to brain damage(5), behavioral symptoms, seizures, or intellectual deficiencies. The primary treatment for Phenylketonuria requires the patient to follow a low protein diet(6) throughout their childhood to avoid aggravating their Phe levels.
An inherent disorder, Homocystinuria affects children and makes them unable to process the amino acid methionine. The methionine and the amino acid homocysteine buildup disrupt vital functions, causing severe weight gain or loss, severe nearsightedness, and other developmental complications.
The main treatment(7) for Homocystinuria includes a diet that reduces the intake of the two amino acids, which you can achieve by following a very low-protein diet.
Note: You can resume a high carb low protein diet after consulting with your doctor to ensure that you receive the required energy through your meals.
| The structure of a protein can cause your immune system to react. For instance, some people are allergic to gluten(8), the protein found primarily in wheat, rye, and barley. |
While your diet needs to be customized to suit your condition, you can go through the following section of low protein foods divided based on the content of protein in them to create the ideal diet plan.
| Foods (100 gm) | Protein (gm) |
| Fruits | |
| Apple | 0.3 |
| Grape | 0.6 |
| Grapefruit | 0.8 |
| Peach | 0.9 |
| Banana | 1.1 |
| Vegetables | |
| Carrot | 0.9 |
| Tomato | 0.9 |
| Onion | 1.1 |
| Asparagus | 2.2 |
| Broccoli | 2.8 |
| Mushroom | 3.1 |
| Grains | |
| Oatmeal | 2.5 |
| Brown Rice | 2.6 |
| White Rice | 2.7 |
Of course, other foods that are low in protein can also be included in your diet. This table is merely aimed at giving you a general idea for what you may include in your protein-restricted diet.
Note: It is not advised to cut protein entirely from your diet. Proteins are essential to your growth and development, and a no protein diet can affect your health adversely.
| Insects contain high levels of protein; even more than some popular meats. For instance, crickets are 69% of protein, while beef is only 29%. |
The following foods have high protein-value, and it is best to have zero or very low consumption of them when on a low protein diet.
If you’re living with a condition that affects your protein metabolism and strains your kidneys or liver, a low-protein diet is the best treatment plan for you. However, if you do not suffer from any such conditions, no evidence suggests that you should follow a low protein diet.
Before starting on a low protein diet, ensure that you consult your doctor or dietician. They will be able to determine if it is a good option for you and will also help you minimize potential health risks and nutritional deficiencies you should follow.
Yes, you can lose weight on a low protein diet. However, that may only be because of loss of muscle mass, which is not recommended. A low protein diet for weight loss is not a good option if losing weight is your primary purpose.
Consuming protein-rich food can strain the kidneys of kidney patients and create severe complications. This is because the kidneys filter the waste in proteins and when they are not functioning properly, the waste builds up and enters your bloodstream. So, kidney patients (not on dialysis) are recommended a low protein diet to avoid unnecessary strain on their kidneys.