Bladderwrack (Fucus vesiculosus) is an edible brown seaweed. It’s available in dried, powdered, and capsule forms for internal and external use. Bladderwrack has important nutrients like fiber, iodine, and antioxidants that can support overall health.
Here are five of the potential benefits of using bladderwrack:
1. Helps Fight Inflammation
Bladderwrack contains antioxidants, which are substances that protect cells and may help fight inflammation. Inflammation is your body’s natural response to injury or infection. It can cause swelling and discomfort that significantly impacts your range of movement.
Some research suggests that taking bladderwrack supplements can improve arthritis and other inflammatory conditions like inflammatory bowel disease, osteoarthritis, and cirrhosis (a chronic liver disease).
2. Improves Skin
Bladderwrack may help skin health because it’s packed with vitamins and minerals that support a healthy glow.
Bladderwrack may have the following effects on skin:
- Protect your skin from damage caused by pollution and the sun
- Promote the production of collagen, a protein that helps keep skin firm and hydrated
- Help protect against natural aging
- Reduce wrinkles
- Brighten skin
- Decrease skin thickness
Some people use bladderwrack in lotions and creams to help nourish skin and improve cellulite, which causes dimples and wrinkles. More research is needed to understand how the seaweed impacts skin health.
3. Improves Thyroid Function
Bladderwrack is a good source of iodine and so can help support thyroid health.
Iodine is a mineral found in some foods and helps the thyroid make hormones. The thyroid is a small gland in your neck that plays a key role in producing hormones and regulating metabolism. Without enough iodine, the thyroid can’t do its job, and you may experience fatigue and weight gain. Bladderwrack may help you get enough iodine for your thyroid. Although the amount of iodine in bladderwrack isn’t always consistent, so proper dosing based on needs can be difficult.
Too much iodine can also cause thyroid issues, so discuss including bladderwrack in your diet with your doctor before using it.
4. Supports Gut Health
Bladderwrack may also be good for gut health. Seaweed is rich in dietary fiber, which helps support a healthy digestive tract and bowel movement schedule.
Bladderwrack may also contain prebiotics, which feed good bacteria to your gut. By feeding the good bacteria in the gut, bladderwrack supplements may improve digestion and encourage regular bowel movements.
5. Helps With Wound Healing
Bladderwrack may also help wounds heal faster because it’s rich in iodine, magnesium, calcium, and antioxidants. Taking bladderwrack supplements may help the skin repair itself after an injury.
Bladderwrack is available in many forms, including powder, pills, capsules, and liquids. Some people drink it in their tea. Others apply bladderwrack directly to the skin.
There isn’t much evidence-based research on bladderwrack seaweed, so there aren’t standardized recommendations for dosing or an ideal time of day to take it. If you’re planning on taking bladderwrack, make sure to read the instructions on the product labels and discuss use with your doctor.
Dosage
Research on bladderwrack is very limited. There currently is no standardized dose for bladderwrack in any form, and recommendations vary between products. Some studies show 100-milligram doses are effective, while others have used 300-milligram or even 500-milligram doses.
It can be dangerous to take too much bladderwrack, so it’s important to read the dosing instructions carefully and discuss new supplements with your doctor before starting.
When taken orally: Bladderwrack can be unsafe for some people when taken by mouth. It contains high levels of iodine, which may cause toxicity when consumed in large amounts. People with thyroid disorders should be cautious with bladderwrack supplements.
When applied to the skin: Bladderwrack is considered safe to apply topically to the skin. However, people who are pregnant or breastfeeding should avoid taking bladderwrack due to the high levels of iodine. Additionally, you may need to stop taking bladderwrack supplements at least two weeks before surgery because it can slow blood clotting and even cause you to bleed more.
How to buy a safe supplement: Make sure the product is independently tested. The U.S. Food and Drug Administration doesn’t regulate supplements. This means that the quality and safety of supplements can vary. Independent testing confirms that the supplement contains the ingredients listed on the label and is free from harmful contaminants. Check for seals from reputable organizations such as NSF International, USP (United States Pharmacopeia), or ConsumerLab.
Potential Drug Interactions
Bladderwrack may interact or interfere with some medications. You should avoid taking bladderwrack if you’re currently on any of the following medications or supplements:
- Amiodarone: Sold under brand names like Cordarone and Pacerone, amiodarone is used to treat certain serious types of arrhythmia (irregular heartbeat). Amiodarone and bladderwrack both contain iodine, and taking them together may increase iodine levels in your blood, affecting thyroid health.
- Lithium: This is used to treat mental health conditions like bipolar disorder. Lithium and bladderwrack impact thyroid function. Taking both together may cause significant fluctuations in thyroid health.
- Antithyroid drugs: These are typically used to treat hyperthyroidism, a condition that causes the thyroid to make more hormones than normal. The iodine in bladderwrack may change thyroid function and affect the effectiveness of antithyroid drugs.
- Blood thinners: Bladderwrack may increase your risk of bleeding when combined with blood-thinning medications.
- Thyroid hormone medications: The iodine in bladderwrack may increase the effectiveness of thyroid medicines or cause adverse side effects.
- Medications changed by the liver: These are medicines the liver can change and break down. Bladderwrack may affect how fast the liver breaks down some medications.
- Supplements that slow blood clotting: Bladderwrack may slow blood clotting and increase your risk of severe bleeding.
- Iodine-containing supplements: Taking supplements that have iodine in them alongside bladderwrack may lead to high iodine levels in your blood.
- Strontium: This supplement promotes bone health and can help with conditions like osteoporosis. Bladderwrack may reduce the body’s absorption of strontium.
Can You Take Too Much Bladderwrack?
It’s possible to take too much bladderwrack. Bladderwrack contains iodine, and consuming too much iodine may cause thyroid issues. High levels of iodine may disrupt your thyroid hormone production and can cause adverse side effects.


