What is lymphedema?
Lymphedema is the build-up of a type of fluid, called lymph, in bodily tissue. Lymph is one of three main components in the lymphatic system, which is part of the immune system. The other two main components are lymphatic vessels and lymph nodes.
Lymph flows between cells, supplying nourishment and carrying away germs, abnormal cells (like cancer cells), and extra fluid. Lymph travels throughout the body via lymphatic vessels and then gets emptied into lymph nodes, which contain white blood cells that help kill germs. When lymph nodes fight off an infection, they get bigger and easier to feel. While you might be most familiar with the lymph nodes in your neck, they’re present throughout your body.
An injury or blockage in the lymphatic vessels, or an increase in the volume of lymphatic fluid present that exceeds the system’s transport capacity, can cause lymph to build up and cause symptoms of lymphedema, such as:
- Swelling in your upper (arms and hands) and lower (legs and feet) extremities
- Changes in skin color
- Limited joint mobility
- Ill-fitting clothes, such as shoes
- Recurrent infections, especially a type of skin infection called cellulitis
Different types of lymphedema
There are two main types of lymphedema: primary and secondary. The key difference between these two is the underlying cause.
Primary lymphedema is a rare inherited condition caused by mutations in genes responsible for the development of the lymphatic system. Secondary lymphedema is more common, accounting for 95% of all lymphedema cases. It typically arises later in life due to lymphatic system damage, which is caused by other conditions or treatments, including:
- Cancer and cancer treatments including radiation and surgery
- Infections, especially repeated infections to the affected extremities
- Inflammatory disorders
- Other forms of chronic lymphatic overload including trauma, burns, and chronic venous insufficiency
Obesity-related lymphedema is a type of secondary lymphedema. Obesity, typically defined as a body mass index (BMI) of 30 or higher, is an independent risk factor for lymphedema. Although the mechanism is not fully understood, it is thought that excess adipose, or fat tissue, partly reduces the lymphatic system’s transport capacity, thereby affecting the flow of lymph.
How obesity affects the lymphatic system
Despite growing research, it’s not yet clear exactly how obesity contributes to lymphatic dysfunction. One study, conducted in mice, supported the idea that obesity causes a build-up of inflammatory T-cells around the lymphatic vessels. Another animal study suggested the link lies in genes that regulate how the body makes and uses fat.
And one 2023 study found that people who have lymphedema and a BMI of 40 or higher also have other medical conditions like heart disease and diabetes. These additional conditions might impair interstitial venous return, which means lymph can’t flow freely back to the center of the body and accumulates in the extremities instead.
Why lymphedema can make weight loss difficult
Many experts recommend weight loss to improve lymphedema. Still, people with lymphedema face challenges in meeting weight loss goals. These include:
- Physical discomfort and limited mobility: Lymphedema increases fluid in the extremities, causing feelings of pain and heaviness.
- Emotional factors: Living with lymphedema can also contribute to mental health issues such as stress, anxiety, and depression, which in itself can make it harder to lose weight.
Overcoming such weight-loss challenges often requires a multi-step approach. Common recommendations include:
- Diet adjustments
- Physical activity
- Emotional support
Treatment for lymphedema
As a chronic condition, lymphedema isn’t curable, but it can be managed. Even with treatment, damage to the lymphatic system, especially the lymphatic vessels, isn’t entirely reversible. Instead, the goal is to reduce symptoms as much as possible and typically requires lifelong care. There are a variety of treatment options, and effectively managing symptoms typically requires more than one of them.
- Compression therapy: Compression stockings and bandages can help prevent fluid build-up and promote the flow of lymph. It’s best to see a specialist to get fitted for these garments, because ill-fitting ones can cause skin irritation and infections.
- Physical therapy and lymphatic massage: Manual lymphatic drainage is a specialized form of massage involving slow, gentle stretching movements. It helps encourage the flow of lymph fluid from the extremities to the body’s center. Different types of physical therapy exercises can also aid in lymphedema management.
- Skin care: Maintaining healthy skin and nails helps prevent infections, which are a common lymphedema complication. Keeping skin clean and moisturized with unscented lotions, as well as ensuring that skin is completely dry, especially between the toes and any skin folds, is also important.
- Diet and weight management: Many studies have shown that weight loss improves lymphatic function by decreasing inflammation and improving insulin sensitivity and heart function. Cutting calories and increasing physical activity are the most commonly recommended weight-loss methods. But depending on how advanced the lymphedema is, some forms of exercise might come with risks. Check with your healthcare provider before starting an exercise routine to discuss an optimal routine, and whether or not you require a properly fitted compression garment during exercise. At this point, the impact of weight-loss medications, such as GLP-1 agonists, on lymphedema symptoms remains unclear. But they can help with weight loss overall, which may improve symptoms.
- Surgical options: Surgery for lymphedema might be advised for people who don’t respond to other treatment options, or who have intractable pain or recurrent infections.
Lymphedema treatments should be tailored to meet a patient’s individual needs. It’s important to work with a healthcare provider to come up with a plan that suits your lifestyle, health history and specific combination of symptoms.