Dietary changes may be part of your management plan for IgA nephropathy (IgAN), a type of kidney disease that can cause long-term health complications, including kidney failure.
Diet affects kidney health both directly and indirectly. It can also affect blood pressure, fluid balance, and blood sugar, all of which affect kidney workload.
A diet high in sodium, for example, can lead to increased blood pressure, which can worsen damage in the kidneys from conditions like IgA nephropathy (IgAN).
If you’ve been diagnosed with IgAN, your doctor may recommend dietary changes that support kidney function.
IgAN is a kidney disease that can lead to chronic kidney disease (CKD), a progressive decline in kidney function.
Also known as Berger disease, IgAN is caused by the immune system producing high levels of antibodies, namely immunoglobulin A (IgA), in the
The glomeruli are specialized vessels involved in blood filtration. They’re located within larger filtration structures called the nephrons. Chronic inflammation from deposits of antibodies can lead to damage and scarring over time, which reduces the kidneys’ ability to function.
IgAN is considered one of the
Diets that focus on kidney health and reducing the workload of the kidneys are known as “kidney-friendly” diets. They usually include initiatives like lowering salt intake, limiting protein, and staying hydrated.
Currently, there are no universal dietary guidelines for IgAN, but eating with kidney health in mind may help support the targeted therapies in your IgAN treatment plan.
Low sodium
Restricting the amount of salt (sodium) in your diet is the only dietary change specifically for IgAN that is largely supported by research.
Lowering your sodium intake helps regulate your blood pressure by reducing how much water is pulled from your tissues into the bloodstream. High sodium in the blood means high fluid volume, which means increased pressure in your vessels.
Over time, that pressure can damage the vessels in your kidneys, compounding the damage already present from IgAN.
The IgA Nephropathy Foundation recommends keeping daily sodium intake at or under 1,500 milligrams (mg). It’s best to speak with your doctor or dietitian to figure out your sodium intake.
Low potassium
Your doctor will let you know if your potassium levels are too high in IgAN. Potassium is an essential mineral and electrolyte in your body, but as your kidneys become damaged over time, they’re less capable of filtering excess potassium out effectively.
When potassium becomes elevated (hyperkalemia), it affects how your muscles (including your heart) function. This can lead to a variety of challenges, from general muscle weakness and paralysis to irregular heart rhythm and cardiac arrest.
If your doctor recommends potassium restriction, the exact amount will depend on the extent of your kidney disease. Daily intake recommendations generally fall under 3,000 mg. It’s best to speak with your doctor or dietitian to figure out your daily potassium intake.
Protein consumption
One of the hallmark clinical signs of IgAN is the loss of protein through your urine, known as proteinuria. This happens due to glomeruli damage, when the membranes that typically keep large molecules like protein within the blood become more permeable.
Eating a diet high in protein, particularly animal protein, can affect kidney health in
A low protein diet for CKD is typically
If you’re on dialysis for advanced kidney disease, your protein recommendations may be increased to compensate for protein filtered out mechanically.
Hydration
Consuming enough fluids during the day is important for your kidney health. When you’re dehydrated, the fluid volume in your blood decreases, meaning waste products become more concentrated and the workload on your kidneys increases.
Staying hydrated helps regulate blood pressure and also helps the body flush out toxins that may be in your urinary tract. Infections in your urinary tract can contribute to chronic kidney inflammation that might worsen kidney damage.
Your recommended fluid intake can vary based on individual factors. A large-scale study from 2021 suggested that people living with CKD consume between 1 to 2 liters of water a day. Speak with your doctor or dietitian about your individual fluid needs and restrictions.
Plant-based foods
Your doctor may recommend a plant-based diet for IgAN. Plant-based diets are often used in CKD because they:
- have a lower protein load
- generate fewer waste products during digestion
- are lower in sodium
- have an abundance of micronutrients
- are lower in cholesterol
- have a low glycemic index to help stabilize blood sugar levels
- support optimal weight through lower caloric density and higher satiety
Vitamins
Kidney-friendly diets and treatments for conditions like IgAN can affect your body’s access to and usage of essential vitamins and minerals.
Your doctor may recommend taking a vitamin supplement to ensure you’re getting the correct levels of these micronutrients.
Speak with a dietitian
The use of diet in the management of CKD is well-studied, but its applications in IgAN, specifically, are less clear.
Before making any changes to your diet, consult with your doctor and consider bringing in a dietitian. Dietitians can help you create structured meals plans that work around your preferences and individual medical needs.
IgAN is a type of kidney disease that can lead to CKD, a progressive decline in kidney function over time.
While research is limited on the application of diet in IgAN specifically, focusing on kidney-friendly diet tips used in CKD may support your overall kidney health.
Before making any dietary changes, discuss the decision with your doctor to ensure you’re meeting your individual needs.