Cholesterol is a waxy, fat-like substance that is found in the body and in the food you eat. It is used by your body to build cells, produce hormones, vitamin D, and substances that help you digest food. Although cholesterol is not inherently “bad”, too much can pose health risks. There are some connections between cholesterol and kidney disease. Learn them here.
Cholesterol is transported through the bloodstream in particles called lipoproteins. There are two main types of cholesterol:
- Low-Density Lipoprotein (LDL): Known as the “bad” cholesterol, LDL carries cholesterol from the liver to cells. Excess LDL in the bloodstream builds up on artery walls, forming plaques that narrow and block blood flow, increasing the risk of heart disease.
- High-Density Lipoprotein (HDL): Known as the “good” cholesterol, HDL helps remove cholesterol from the bloodstream and transport it back to the liver for processing and elimination. Increased HDL is associated with a lower risk of heart disease.
Another type of “bad” cholesterol is called Triglycerides. This is the main form of fat in the body.
It is important to maintain a balance between LDL and HDL cholesterol levels in your body. High levels of LDL cholesterol and low levels of HDL cholesterol are risk factors for cardiovascular diseases such as heart disease and stroke.
Tests for Cholesterol and Kidney Disease
Cholesterol tests involve blood tests aimed at measuring lipids. Lipids are present in the bloodstream and play a vital role in cellular structures and the maintenance of normal bodily functions. Cholesterol, triglycerides, HDL, and LDL are all part of the lipid profile.
Cholesterol and triglycerides tests measure:
- HDL Cholesterol Levels
- LDL Cholesterol Levels
- Triglyceride Levels
- Total Cholesterol Levels
Other measurements include:
- The ratio of LDL to HDL
- The ratio of total cholesterol to HDL
- Very-low-density lipoprotein (VLDL) levels
The results of these tests can be used to prevent, monitor, or diagnose a medical condition or the risk of having heart and blood flow issues, including heart attack and stroke. In addition, blood pressure, age, sex, race, and other medical conditions such as diabetes can be factors used to calculate risk.
Cholesterol and Kidney Disease
CKD and cholesterol are interconnected such that abnormal cholesterol levels are a hazard to the kidneys. Studies indicate that those with high total cholesterol or reduced HDL (“good”) cholesterol are more likely to have reduced GFR. Individuals with high cholesterol are twice as likely to develop CKD over time. These connections include:
- Atherosclerosis: High levels of LDL (“bad”) cholesterol can contribute to atherosclerosis, impacting not only the coronary arteries (leading to heart disease) but also the renal arteries, which supply blood to the kidneys. Reduced blood flow to the kidneys can contribute to CKD.
- Hypertension: High cholesterol is associated with high blood pressure, which is a large risk factor for both heart disease and CKD. Chronic high blood pressure can damage the blood vessels in the kidneys, impairing their ability to filter waste products from the blood.
- Diabetes: Diabetes is a common risk factor for both CKD and heart disease. High cholesterol levels can exacerbate diabetes-related kidney damage by increasing inflammation and oxidative stress in the kidneys.
- Diet and Lifestyle: Diets high in cholesterol and saturated fats contribute to obesity, diabetes, and high blood pressure (all CKD risk factors). A heart-healthy diet and lifestyle can help manage cholesterol and reduce the risk of heart disease and CKD.
Managing cholesterol, blood pressure, and diabetes through lifestyle changes, dietary changes, and other interventions can reduce the risk of heart disease and CKD progression. Check out programs like Kidney Nutrition Fast Track to help get you started.
Cholesterol comes from two sources: the liver and dietary cholesterol. The cholesterol consumed comes from animal sources such as meat, poultry, and dairy products and tropical oils such as palm oil which are high in saturated and trans fats can increase our blood cholesterol levels. When thinking about nutrition changes, here are some to keep in mind:
- Reduce your intake of salt, red meat, processed meats, and sugary beverages.
- Opt for foods that have reduced levels of saturated fat, trans fats and cholesterol by reading food labels.
- Boost your intake of soluble fiber, which can be obtained from sources such as fruits, vegetables, and grains.
- Choose heart-friendly oils such as olive oil or other oils with less than 4g of saturated fat per tablespoon, and no partially hydrogenated oils or trans fats.
- Aim to include more plant-based proteins like nuts each day or legumes like lentils, chickpeas.
- Increase physical activity to 30 minutes daily at a moderate level.
Individual dietary needs can vary based on the stage of CKD, overall health, and other factors. It’s vital to collaborate with your renal dietitian to create a nutrition plan that addresses both cholesterol levels and CKD while ensuring you receive adequate nutrients to maintain health. If you need help getting started, send us a message.
This article was written by Neha Dewan, Nutrition Student Volunteer.
This article was reviewed by Emily Campbell, RD CDE MScFN.