True kelps belong to the genus laminaria, family Laminariaceae. Giant kelps belong
to the genus macrocystis, family Lessoniaceae. Bladder kelps belong to the genus nereocystis,
Kelp is a common name for leafy algae or seaweed.
Kelp needs sunlight as an energy source. It also needs a hard surface (not sand) on
which to grow. Kelp grows quickly. In fact, giant kelp is one of the world's fastest
growing plants. It grows as much as 300 feet (100 meters) in a single year.
Kelp contains iodine. This provides the trace element for your thyroid hormone.
Medically valid uses
Kelp is a food staple. It’s also used to make a group of compounds called alginates.
These include carrageenan. Alginates are used in the food industry to stabilize and
improve the textures of foods. These include ice cream and chocolate milk. The thick,
smooth feel of chocolate milk is made by adding alginates. They’re also used in toothpaste
Kelp is also used as soil conditioners. It adds organic material to soil that doesn't
have enough nutrients.
As a supplement, kelp is used as a natural source of iodine. But the average laminaria-based
supplement might contain large amounts of iodine. This can cause decreased thyroid
function (hypothyroidism) or increased thyroid function (hyperthyroidism). If you
already have hyperthyroidism, it can make your condition worse. Some supplements
may also contain arsenic. There isn’t enough information to know if kelp supplements
There may be benefits that have not yet been proven through research.
Kelp may improve sensory receptors. It may also promote healthy nails and blood vessels,
aid in digestion, and ease constipation. It may also reduce hair loss and help with
diabetes and weight management. Kelp may treat gastrointestinal ulcers. It’s also
claimed to reduce the risk of breast cancer.
Kelp comes in powder and capsule form. Follow the instructions on the package for
the correct dose.
Talk with your healthcare provider before taking any types of supplements.
Side effects, toxicity, and interactions
Both hyperthyroidism and hypothyroidism have been linked to too much kelp intake.
This is due to its high amount of iodine. Abnormal thyroid function has also been
linked directly to too much use of kelp supplements.
Kelp may contain harmful metals. These include cadmium, lead, aluminum, and other
heavy metals. This is more likely if you eat a lot of kelp from areas of contaminated
Women who are pregnant or breastfeeding shouldn’t use kelp supplements.
If you’re being treated for thyroid issues, you shouldn’t take kelp. You also shouldn’t
use it if you take certain heart medicines.
If you need an X-ray with a contrast media, talk to your healthcare provider. You
may have to stop taking kelp 1 month before your X-ray. You may not be allowed to
take it again until the contrast medium leaves your body.