Processed meat products such as sausages, ham or cold cuts often contain high levels of sodium, phosphorus and preservatives such as nitrite.
These are substances that can increase pressure on the kidney's filtration system. A study published in the European Journal of Clinical Nutrition in 2025 showed that phosphorus and potassium additives in ultra-processed foods can cause mineral imbalances and worsen kidney failure, especially in people at high risk.
A breakfast with a hamburger or sausage can provide up to 50-70% of the recommended amount of sodium per day. Excess sodium causes water retention, high blood pressure and increases glomerular filtration pressure - a major factor promoting the progression of chronic kidney disease.
Regular consumption of processed foods, especially processed meat, can worsen kidney function due to high sodium and additive levels, while increasing the risk of cardiovascular complications in people with kidney disease.
Many long-term observation studies have recorded a link between a diet rich in processed meat and the risk of chronic kidney disease.
Biological hypotheses suggest that nitrite preservatives and compounds formed during smoking can cause oxidative stress and chronic inflammation - two mechanisms that contribute to damaging nephrons (kidney filtering units).
Epidemiological analyses also show that consumption of processed meat is associated with high blood pressure and metabolic disorders - the main risk factors leading to kidney failure.
Some studies also show that switching to a diet rich in fresh foods, whole grains and less processed protein can slow down the progression of chronic kidney disease in the early stages.
Instead of sausage sandwiches or cold cuts, experts recommend options such as: boiled eggs or low-fat omelets; oatmeal porridge or whole wheat bread; yogurt, fresh fruits and nuts.
These foods provide protein, fiber and essential vitamins without overloading sodium or phosphorus to the kidneys.
