Lymphatic drainage massage has been trending in recent years, with celebrities and health personalities alike claiming it can help flush out toxins, give your immune system a boost and even help you shed unwanted pounds. But is it legit? And who can benefit?

“Lymphatic drainage massage is a gentle massage that targets the lymphatic system, which resides just beneath the skin,” said Mae Murakami, a physical therapist at Cedars-Sinai. “It can be a powerful tool for people whose lymphatic system is compromised from surgery, illness or injury.”

Unfortunately, lymphatic drainage is often misunderstood. Here, Murakami provides answers to some of the most pressing questions about lymphatic drainage massage.

The lymphatic system is a network of vessels and organs that lie beneath the skin, and it’s a critical component of a healthy immune system. In fact, your lymphatic system acts almost like a garbage disposal, helping your body filter out waste and bacteria.

Lymphatic drainage massage, which is sometimes called manual lymphatic drainage, or MLD, involves gently massaging areas of the body to help move lymph fluid to an area with working lymph vessels.

Normally, the lymphatic system collects lymph fluid and returns it to your heart through the lymph vessels and nodes. But when there’s a disruption to your lymphatic system’s process, such as the removal of lymph nodes during surgery for breast cancer, the fluid can collect in your arms and legs, which leads to swelling. The medical term for swelling is edema, so the condition is called lymphedema.

Certified therapists commonly use MLD to relieve swelling by coaxing lymph fluid from your tissues to your functioning lymph nodes. Unlike traditional massage, lymphatic drainage massage uses light pressure to mobilize the lymphatic system, which lies directly beneath the skin.

MLD follows a specific sequence, starting with the main drains in the body, including the lymph nodes in the neck, groin and armpits. The idea is that by massaging an area where there is no swelling, the congested lymph fluid will have somewhere to go because you’ve created space for it.

All our cells rely on lymph fluid to boost immunity and transport waste products. So theoretically, a congested lymphatic system can compromise your immune system. And since lymph fluid is full of disease-fighting white blood cells, stuck fluid can contribute to a host of issues, including lymphedema.

The most obvious sign of a compromised lymphatic system is swelling. Like the blood that’s part of your circulatory system, lymph fluid is constantly moving. If it stops, lymph fluid can build up and create swelling, usually in the arms and legs. If your rings feel tight or your clothes begin to feel a bit snugger, that could be a sign that you’re holding on to excess fluid. You might also experience pain and a feeling of heaviness.

Most of the time, lymphatic vessels become congested as a result of surgery, infection, trauma or diseases like cancer. So, chances are good that if your lymphatic system is suffering, you’d know it. Infection and tight muscles may also be signs of congestion.

In addition to cancer, conditions such as rheumatoid arthritis, fibromyalgia, chronic venous insufficiency (which happens when your leg veins aren’t working correctly) and lipedema (where abnormal fat accumulates in your body) can cause lymphedema.

If you have a healthy lymphatic system, lymphatic drainage massage isn’t likely to benefit you beyond simple relaxation. And despite celebrities claiming that lymphatic drainage massage makes them “red-carpet ready,” there’s no evidence that lymphatic drainage massage can help you slim down.

Instead, using lymphatic drainage techniques may have a temporary trimming effect because it helps move fluid through the body (like spreading a stack of papers from one end of the counter across the entire surface).

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Yes, and the technique is simple. The idea is to use very light pressure to massage the area and push fluid that’s causing swelling back toward the heart. Move your fingers in a motion that creates the letter “C,” gently massaging tissues that are NOT swollen.

Since lymphatic drainage massage acts on the skin, it’s important to avoid using oils or lotions during the massage.

There are other ways to pamper your lymphatic system, too, including:

• Deep breathing. Breathing slowly and deeply can help move fluid through the lymph vessels and nodes. Place both hands on your belly and focus on expanding your belly as you inhale and contracting your belly as you exhale.
• Physical activity. Exercise helps move fluid throughout the body. Even a 15- to 20-minute stroll can help your body shift fluid around and eliminate waste. A short jog while focusing on deep breaths also does the trick.
• Dry brushing. Dry brushing has gained popularity in recent years for its ability to keep the lymphatic system healthy while exfoliating the skin. Just move the brush in circular motions starting at the extremities and working your way toward the trunk of the body.
• Swimming. Moving through water provides built-in compression for your body, so swimming is a great way to get your lymph fluid moving.
• Tap your skin. Tapping the area just above the collarbones with light pressure can activate the lymph capillaries beneath the skin.

If you think that your lymphatic system may be compromised, talk to your doctor before attempting to do MLD on your own at home.

“If you have lymphedema, it’s important to work with a certified lymphedema therapist who is specially trained in lymphatic drainage massage and can teach you how to do the proper techniques,” said Murakami. “It’s also important to note that lymphatic drainage techniques are not recommended for people who have a heart condition, kidney problems or cellulitis.”