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10 Reasons to Try Seaweed

Not just for sushi anymore, seaweed and other marine-based supplements are popping up everywhere as a natural way to boost your immunity, cleanse your body of toxins, and protect you from heart disease and cancer.

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Whether they’re eating it or soaking in it, coastal cultures have for centuries revered seaweed for its abilities to heal and nourish the body. “It helps my skin look more youthful than my biological age, gives me life-sustaining minerals for good health, and fulfills cravings for salty food,” says Valerie Gennari Cooksley, RN, author of Seaweed: Nature’s Secret to Balancing Your Metabolism, Fighting Disease, and Revitalizing Body and Soul. This low-calorie, fat-free snack contains 10–20 times more minerals and vitamins than any land vegetable. So grab a fork and dive in.

1. For Thyroid and Weight Control

Seaweed supplements are a popular component in many natural weight-loss programs. Algin in kelp and carrageenan in red seaweeds are both thought to stimulate weight loss. The high fiber content of sea greens helps dieters feel satiated, while aiding in intestinal function.

Metabolism is an important element in weight management,. People with low levels of iodine tend to metabolize food more slowly and as a result, may end up storing more fat. Sea greens are loaded with iodine—1,000 times more than any land plant.

2. Smart for the Heart 

Seaweed packs a one-two punch against cardiovascular disease: It helps lower blood pressure and reduce cholesterol. Cooksley writes, “kelp has an ideal ratio of potassium to sodium,” which helps control hypertension. Studies show that fucoidan (a plant-derived complex sugar molecule that stimulates immune-cell growth) in seaweeds such as bladderwrack promotes lipid metabolism in the liver, resulting in lower cholesterol levels. And seaweed appears to strengthen weak and diseased blood vessels and help dissolve plaque buildup in arteries—culprits in heart disease. Cooksley suggests making your own sea flax oil: Combine 8 teaspoons of bladderwrack powder with 8 ounces of organic flaxseed oil. Use in smoothies or drizzle on salads and cooked grains.

3. Cancer Fighter

Many experts attribute the low rates of breast, colon, and lung cancers in the Japanese in part to their high consumption of seaweed. Seaweeds prevent and slow the growth of cancerous cells without the side effects that Western medicine can produce. Kelp’s anticancerous properties are fucoidan, lignan, and iodine, Cooksley writes in Seaweed. Additionally, she says fucoidan appears to work by boosting the immune system, helping to destroy and prevent the replication of cancer cells. Lignans, also found in flax, whole grains, fruits, and vegetables, are converted into molecules that are known to reduce estrogen levels. Lower estrogen levels reduce the risk of estrogen-related cancers, such as breast cancer.

4. Detoxifier

Every day we are bombarded by environmental toxins. Alginates, particularly the ones found in brown seaweeds, may protect and rid cells of toxins and help the body excrete heavy metals. The alginates in kelp, for example, are thought to bind with toxins in the intestines and carry them out of the body. Brown seaweeds cleanse the colon of noxious chemicals, aiding in a healthy gut. 

5. Natural Sea Spa

Seaweed wraps are anything but passé in the spa world. Rumored to have been used by Cleopatra for its skin-smoothing and anti-aging properties, seaweed is no longer a beauty secret. Lotions, mud packs, massage oils, and scrubs contain seaweed extracts for glowing skin—our largest organ, and the one from which most toxins are eliminated. Additionally, lack of oxygen to cells is a major culprit in the aging process, and iodine-rich seaweeds like kelp and bladderwrack stimulate oxygenation. 

6. Wound Mender

Mothers know the value of iodine for cuts, scrapes, and burns. It’s also a powerful disinfectant used to prevent infection in medical facilities around the world. Along with iodine, red and brown seaweeds produce healing gels made up of alginates that help prevent scarring. Cooksley recommends adding seaweed powder to baths to help heal insect bites and inflammatory skin conditions such as rashes and eczema. 

7. Lets You Breathe Easy

Research suggests that breathing seaweed-enhanced steam is an effective treatment for respiratory problems, especially those caused by allergies. Seaweed helps boost immunity to environmental toxins, improve mucus production to relieve congestion, and flush irritants from the body. When digested, sea greens may protect and promote proper lung function.

8. Add Flavor to Foods

Seaweed makes a tasty, nutritious addition to many dishes. Try brown seaweeds like wakame mixed with lettuce in a salad, and kombu in miso soup. Agar’s sweet flavor goes well in gelatin-like desserts, and arame’s nutty taste is good sautéed with onions and carrots or scrambled in eggs. Try sprinkling buttered dulse over popcorn, suggests Cooksley. Or try our Crab and Seaweed Salad.

9. A Vitamin and Mineral Boost 

Seaweed offers essential vitamins and minerals and is high in calcium, fiber, phosphorus, potassium, magnesium, iron, sodium, protein, and iodine. It contains vitamins A, C, D, E, and K, and some seaweeds even contain B12, which is important for vegetarians because B12 is normally found only in animal products. The one seaweed no one should live without? Laminaria, also known as kombu or Atlantic kelp. According to Cooksley, this nutritional powerhouse does everything from helping to regulate blood sugar, relieving congestion, and easing lymphatic swellings, to firming, toning, and revitalizing the skin. 

10. Small Doses, Big Results

Cooksley says raw seaweed—dried, reconstituted, or fresh—is the best way to get all of the active enzymes. But liquid and powdered varieties
offer the next best thing because these supplements can be easily digested and absorbed into the body. Cooksley recommends taking
1½ teaspoons of powdered seaweed (or ¼ ounce of dried or flaked) several times a week.