StayWell Guam Inc.

Kidney Basics

The body has two kidneys, each about the size of a fist, located on either side of the spine at the bottom of the ribcage. Each kidney contains about one million functioning units called nephrons. A nephron consists of a filtering unit of tiny blood vessels, called a glomerulus, which is attached to a tubule. When blood enters the glomerulus, it is filtered and the remaining fluid then passes through the tubule. In the tubule, chemicals and water are either added to or removed from this filtered fluid according to the body’s needs. The final product is urine, which we excrete.

The kidneys filter your blood to remove wastes and excess fluid to make urine. They also help to control blood pressure and make hormones that the body needs to stay healthy. Blood enters the kidneys through an artery from the heart where it is cleaned by passing through millions of tiny blood filters. Waste material passes through the ureter and is stored in the bladder as urine. Newly cleaned blood returns to the bloodstream by way of veins. The bladder eventually becomes full and urine passes out of the body through the urethra.

The kidneys perform this function 24 hours a day and filters and returns to the bloodstream about 200 quarts of fluid every day. Approximately two quarts are eliminated from the body in the form of urine, while the remainder, about 198 quarts is retained in the body. The urine we excrete is usually stored in the bladder for approximately one to eight hours.

The kidney’s function is crucial to all parts of the body and are involved in complex operations that keep the rest of the body in balance. Among others, the critical regulation of the body’s salt, potassium, and acid content and the production of important hormones and vitamins is performed by the kidneys, meaning that the failure of the kidneys have serious implications in the overall health of the body.

Causes of Kidney Disease

There are many types of kidney disease, and it usually affects both kidneys. If the kidneys’ ability to filter the blood is damaged by disease, wastes and excess fluid may build up in the body, causing severe swelling and symptoms of kidney failure. The kidneys may be affected by diseases such as diabetes and high blood pressure, while some are congenital, meaning that a physical abnormality is affecting the kidneys.

Diabetes and Kidney Disease

Diabetes is the leading cause of serious kidney disease due to high blood glucose levels, also called blood sugar, that can damage the blood vessels in the kidneys. When the blood vessels are damaged, they don’t work as well. Naturally, having diabetes for a longer time increases the chances that you will have kidney damage. In addition, those living with diabetes usually develop high blood pressure which is another high-risk factor for kidney disease.

High Blood Pressure and Kidney Disease

Adults with high blood pressure, diabetes, or both, have a higher risk of developing chronic kidney disease (CKD) than those without these because over time, uncontrolled blood pressure can harm renal blood vessels. The nephrons in the kidneys which are supplied with a dense network of blood vessels, and high volumes of blood flow through them. Over time, high blood pressure causes arteries around the kidneys to narrow, weaken or harden. These damaged arteries are not able to deliver enough blood to the kidney tissue. The nephrons within the kidneys receive their blood supply through tiny hair-like capillaries, the smallest of all blood vessels. When the arteries surrounding the kidneys become damaged, the nephrons do not receive the essential oxygen and nutrients — and the kidneys lose their ability to filter blood and regulate the fluid, hormones, acids and salts in the body.

Damaged kidneys also cannot regulate blood pressure which is done through a response the kidneys have to a hormone called aldosterone which is produced in the adrenal glands, to help the body regulate blood pressure. This eventually contributes to a negative spiral where the condition of high blood pressure is further compounded due to kidney disease as arteries become blocked and stop functioning, leading the kidneys to eventually fail.

Other Common Kidney Diseases

Diabetes and high blood pressure are two examples of kidney disease risk factors that can quite often be reversed or managed. However, there are other common types of kidney disease that are inherited such as Glomerulonephritis which is a disease that causes inflammation of the kidney’s tiny filtering unites, the glomeruli. As well Polycystic kidney disease is the most common inherited kidney disease which is caused by frequent kidney stones that cause damage to the kidneys. Congenital disease such as Goodpasture’s Syndrome, and reflux disorder are also common kidney diseases.

The Heart and Kidneys

The heart pumps blood filled with oxygen through all parts of the body including the kidneys. Meanwhile the kidneys clean the blood, removing waste products and extra water. Without the kidneys, the bloodstream would have too much waste and water. Meanwhile the heart supplies the kidneys with oxygen filled blooded needed to function properly. Due to the relationship between the heart and kidneys, quite often kidney disease can directly affect your chances of developing heart disease and vice versa.

Preventing CKD

Preventing chronic kidney disease and its complications is possible by managing risk factors and treating the disease to slow its progression and reduce the risk of complications. To keep healthy kidneys, it is important to control those risk factors for CKD that can be modified.

Get Tested for CKD

If you’re at risk, get tested for CKD regularly. Ask your doctor to test your blood or urine. For those living with diabetes you should get tested yearly, and it’s important to remember that CKD has a higher chance of successful treatment and prevention through early detection.

Lifestyle for Healthier Kidneys

As the two main risk factors for CKD are diabetes and high blood pressure, CKD can largely be prevented by making positive lifestyle changes to prevent or manage these health conditions.

Make Healthy Food Choices

Choose foods that are healthy for your heart and your entire body: fresh fruits, fresh or frozen vegetables, whole grains, and low-fat or fat-free dairy products. Eat healthy meals and cut back on salt and added sugars. Aim for less than 2,300 milligrams of sodium each day. Try to have less than 10 percent of your daily calories that come from added sugars.

Tips for Making Healthy Food Choices

• Cook with a mix of spices instead of salt.
• Choose veggie toppings such as spinach, broccoli and peppers for your pizza.
• Try baking or broiling meat, chicken and fish instead of frying.
• Serve foods without gravy or added fats.
• Try to choose foods with little or no added sugar.
• Gradually work your way down from whole milk to 2 percent milk until you’re drinking and cooking with fat-free (skim) or low-fat milk and milk products.
• Eat foods made from whole grains — such as whole wheat, brown rice, oats and whole-grain corn, every day. Use whole-grain bread for toast and sandwiches; substitute brown rice for white rice for home-cooked meals and when dining out.
• Read food labels. Choose foods low in saturated fats, trans fats, cholesterol, salt (sodium) and added sugars.
• Slow down at snack time. Eating a bag of low-fat popcorn takes longer than eating a slice of cake. Peel and eat an orange instead of drinking orange juice.
• Try keeping a written record of what you eat for a week. It can help you see when you tend to overeat or eat foods high in fat or calories.

Tips for Making Healthy Food Choices

Be active for 30 minutes or more on most days. If you are not active now, ask your health care provider about the types and amounts of physical activity that are right for you. Aim for at least 150 minutes per week of moderate-intensity aerobic activity. This includes walking fast, jogging, dancing, or other types of aerobic activities to elevate your heartbeat and breathing. Try to be active for at least 10 minutes at a time without breaks. You can count each 10-minute segment of activity toward your physical activity goal.

You may need at least 300 minutes per week of aerobic activity if your goal is to lose weight or to keep it off. Adding a brisk walk after lunch, dinner, or when your schedule permits may be one way to boost the amount of aerobic activity in your life.

Lastly, do strengthening exercises twicer per week to improve your strength at balance, and make exercising easier for you in the future. To help strengthen your whole body, work all major muscle groups, including those in your legs, back, abdomen, chest, shoulders and arms. Doing 2 to 3 sets for each muscle group twice per week may help. However, even just 1 set of strength training offers benefits.

Stop Smoking

If you smoke or use other tobacco products, it’s important to stop as smoking has major impacts on the entire cardiovascular system. Smoking tobacco products cause buildup in the lungs, and the cardiovascular system in the form of plaque that is difficult for the body to remove naturally. This buildup eventually causes less oxygen to make it into the bloodstream and thus causing damage to the major organs including the heart and the kidneys.

Limit Alcohol Intake

Drinking too much alcohol can increase your blood pressure and add extra calories, which can lead to weight gain. If you drink alcohol, limit yourself to one drink per day if you are a woman and two drinks per day if you are a man.

Manage Stress

Learning how to manage stress, relax, and cope with problems can improve emotional and physical health. Physical activity can help reduce stress, as can mind and body practices such as meditation.

Treating Kidney Failure

Healthy kidneys do many important jobs to keep your whole body in balance. When the kidneys fail, they cannot carry out the important functions to filter the blood. Typically, the kidneys are considered failing when 85-90% of your function is gone and thus your kidneys do not work well enough to keep the body functioning properly.

A physician is the only one who can fully determine whether the kidneys are failing and will prescribe the treatment as necessary. When it comes time to choose a treatment for kidney failure, the decision may often be stressful. Reviewing options and talking with a healthcare team to choose an appropriate treatment plan is the best way to prepare as each option has different advantages and disadvantages. Currently there are two options for treatment of kidney failure: dialysis, or kidney transplantation.

Dialysis (Hemodialysis)

Dialysis is a treatment that removes wastes and extra fluid from your blood. It can be done at home or at a dialysis center. During dialysis, the blood is pumped through soft tubes to a dialysis machine where it goes through a special filter called a dialyzer (also called an artificial kidney). After the blood is filtered, it is returned to the bloodstream.

Kidney Transplantation

A kidney transplant is an operation that places a healthy kidney from one person into another. The kidney may come from someone who has died or from a living donor who may be a close relative, spouse, or friend. It can even come from someone who wishes to donate a kidney to anyone in need of a transplant. However, a kidney transplant is a treatment, not a cure, and it is important to care for the new kidney with the same care as before receiving the transplant.

Build Your Path to Better Kidney Health

Whether you are currently living with kidney disease or have any of the high-risk factors, it is important to plan ahead to care for your kidney health. Although dialysis and kidney transplants are viable options to treat kidney failure, those who undergo dialysis or are living with a transplant are often limited in the way they can eat, the activities they can participate in, and the medical costs associated with these treatments. So, it’s clear that the best solution is to take care of the kidneys you have already as much as possible. Take an active role in your care, and talk to your healthcare provider about your high-risk factors. If you are high risk, or are already living with kidney disease, it’s important to create and follow the care plan you make with your healthcare provider. Lastly, build a kidney healthy lifestyle by incorporating healthy eating habits, staying active, and taking care of your body so that you can live life to the fullest!

If you want to learn more about the important lifestyle changes you can make to care for your kidneys check out these resources:

• Aloha Kidney
• Kidney Basics
• Center for Disease Control and Prevention – Kidney Disease

Sources:

• National Institute of Diabetes and Digestive and Kidney Diseases
• Heart.org – How High Blood Pressure Can Lead to Kidney Disease
• Center for Disease Control and Prevention – Kidney Disease
• Kidney Basics