What Is Kelp? Benefits, Uses & Research | God's Way Herbs

What Is Kelp? Benefits, Traditional Uses, Nutritional Benefits & Herbal Thyroid Support

Kelp is a group of large brown seaweeds that grow in cool, nutrient-rich coastal waters around the world. Unlike most of the herbs commonly used in botanical wellness, kelp does not grow on land—it is a marine algae valued as both a traditional food and a natural source of minerals.

Kelp is especially well known for its naturally occurring iodine, an essential trace mineral the body needs to produce thyroid hormones. It also contains varying amounts of minerals, polysaccharides, carotenoids, and other marine compounds.

Because of this unique nutritional profile, kelp has become particularly associated with normal thyroid function, metabolism, and overall nutritional wellness. However, kelp's high iodine content also means that appropriate amounts matter: both too little and too much iodine can adversely affect thyroid function. (PubMed)

Kelp is included in God's Way Herbs Skeletor Joint & Mobility Support, where its naturally occurring iodine contributes nutritional support for normal thyroid hormone production and thyroid function as part of a comprehensive herbal wellness formula.

What Is Kelp?

Kelp isn't a single plant. The word refers broadly to numerous species of large brown macroalgae belonging primarily to the order Laminariales.

Common kelps include species within genera such as:

• Laminaria

• Saccharina

• Macrocystis

• Alaria

• Ecklonia

One familiar edible kelp is kombu, which is widely incorporated into Japanese and other East Asian cuisines.

Unlike land plants, kelp does not have true roots, stems, or leaves. Instead, its body includes structures called a holdfast, stipe, and blades.

Some kelps can grow to extraordinary sizes, forming underwater environments known as kelp forests.

Depending on the species and environment, kelp may naturally provide:

• Iodine

• Potassium

• Magnesium

• Calcium

• Iron

• Alginate

• Laminarin

• Fucoidan

• Fucoxanthin

• Dietary fiber

• Other naturally occurring marine compounds

Research on Laminaria, for example, identifies iodine, potassium, magnesium, calcium, iron, alginates, and laminarins among its constituents. (PubMed)

Where Does Kelp Come From?

Kelp grows naturally in cool and cold coastal waters, where it attaches to rocky surfaces beneath the ocean.

Large kelp ecosystems can be found along coastlines of:

• North America

• South America

• Europe

• Japan

• Korea

• China

• Australia

• New Zealand

• Other temperate coastal regions

Kelp has been consumed for centuries in many coastal cultures, particularly throughout East Asia.

In Japan, China, and Korea, various seaweeds have long been incorporated into soups, broths, seasonings, side dishes, and traditional preparations.

Modern interest in kelp has expanded well beyond food. Today, kelp-derived ingredients can be found in dietary supplements, foods, cosmetics, agricultural products, and personal-care formulations.

How Is Kelp Used?

Kelp can be consumed as a food or processed into numerous different preparations.

Common uses include:

• Dried kelp

• Kelp flakes

• Kelp powder

• Kombu

• Soups and broths

• Seasonings

• Capsules

• Tablets

• Multi-herb supplements

• Mineral-focused formulas

• Botanical body-care products

• Alginate-containing foods

Kelp-derived alginates are also widely used because of their ability to thicken and stabilize products.

When kelp is used in dietary supplements, one of its most nutritionally significant characteristics is usually its iodine content.

However, iodine concentrations can differ dramatically between kelp species and products. This makes appropriate sourcing, formulation, and serving size especially important. (PubMed)

What Are the Benefits of Using Kelp?

Kelp's potential benefits stem largely from its nutritional and phytochemical composition rather than from one isolated botanical compound.

Supports Normal Thyroid Function

Kelp's relationship with the thyroid gland is perhaps its most important nutritional characteristic.

Kelp naturally contains iodine, and the human body requires iodine to produce the thyroid hormones thyroxine (T4) and triiodothyronine (T3).

These hormones influence numerous physiological processes throughout the body.

The NIH Office of Dietary Supplements identifies seaweed among dietary sources naturally rich in iodine and notes that iodine is required by the body to make thyroid hormones. (ODS)

This means kelp can appropriately be described as providing iodine that supports normal thyroid hormone production and thyroid function when consumed in suitable amounts.

It is important, however, not to translate this into claims that kelp “boosts” the thyroid or treats hypothyroidism. Excess iodine can actually interfere with normal thyroid function. (PubMed)

Supports Normal Metabolism Through Thyroid Nutrition

The thyroid plays an important role in regulating metabolism, including how the body uses energy.

Because iodine is required for thyroid hormone production, obtaining sufficient dietary iodine contributes to the normal metabolic functions regulated by thyroid hormones.

Kelp can therefore contribute nutritional iodine as part of an appropriately formulated wellness routine.

This does not mean that taking additional kelp automatically increases metabolism or causes weight loss.

If someone already consumes sufficient iodine, substantially increasing iodine intake does not simply cause the thyroid to produce progressively more hormones. In fact, excessive intake can disrupt thyroid function.

Provides Naturally Occurring Marine Minerals

Kelp absorbs minerals from the seawater surrounding it.

Depending upon the species and growing environment, it may contain varying amounts of:

• Iodine

• Magnesium

• Calcium

• Potassium

• Iron

• Other trace minerals

These minerals perform different physiological roles throughout the body.

Because mineral concentrations vary considerably among seaweeds, however, kelp should not automatically be considered a standardized source of any nutrient unless the amount has been verified for the specific product.

Contains Unique Marine Polysaccharides

Kelp contains several complex carbohydrates that are uncommon in ordinary land vegetables.

These include compounds such as:

Alginate — a structural polysaccharide responsible for many of kelp's gel-forming properties.

Laminarin — a storage polysaccharide found in brown algae.

Fucoidan — a sulfated polysaccharide that has become an important subject of marine natural-product research.

Scientists are investigating these compounds in areas including nutrition, food science, biotechnology, cellular biology, and natural-product research.

Many proposed health applications remain experimental and should not be interpreted as established clinical benefits from eating kelp.

Provides Fucoxanthin and Other Marine Compounds

Brown seaweeds contain a distinctive carotenoid pigment known as fucoxanthin.

Fucoxanthin contributes to the characteristic brown or olive coloration of many kelp species.

Researchers have investigated fucoxanthin for its antioxidant properties and its interactions with metabolic and cellular pathways.

These studies are scientifically interesting, but much of the research remains preclinical. Fucoxanthin research should therefore not be used to claim that ordinary kelp supplements cause weight loss or treat metabolic disease.

Provides Naturally Occurring Antioxidant Compounds

Kelp contains numerous compounds that have been investigated for antioxidant activity, including carotenoids, polyphenols, and certain polysaccharides.

Antioxidants help the body manage oxidative processes as part of normal physiology.

However, laboratory antioxidant activity does not establish that kelp prevents or treats disease.

Kelp, Iodine, and Thyroid Health

Understanding the relationship between kelp, iodine, and the thyroid is especially important because this is an area where more is definitely not always better.

The thyroid requires iodine to make thyroid hormones.

The recommended dietary allowance for iodine for most adults is 150 micrograms per day, with higher requirements during pregnancy and breastfeeding. (ODS)

Kelp can contain very high concentrations of iodine, and the amount can vary substantially among species and products.

A scientific review specifically examining iodine, seaweed, and thyroid health cautioned that brown seaweeds such as kelp can provide excessive iodine even in relatively small amounts. (PubMed)

A 2026 human study involving habitual seaweed consumers reinforces this concern. Participants had a median estimated iodine intake of 658 micrograms per day while consuming seaweed, which fell substantially after a six-week period without seaweed. Researchers also observed changes in TSH associated with cessation of seaweed consumption. (PubMed)

Therefore, the responsible message isn't simply “kelp is good for your thyroid.”

A more accurate statement is:

Kelp naturally provides iodine, an essential mineral required for normal thyroid hormone production and normal thyroid function. Appropriate iodine intake is important because both deficiency and excessive intake can interfere with thyroid health.

Kelp in God's Way Herbs Skeletor Joint & Mobility Support

Kelp's marine nutritional profile makes it an interesting complementary ingredient within comprehensive herbal formulas.

God's Way Herbs Skeletor Joint & Mobility Support includes kelp as part of its multi-ingredient botanical approach to everyday wellness.

While Skeletor is designed around joint and mobility support, kelp brings an additional nutritional dimension to the formula through its naturally occurring iodine.

Iodine is an essential nutrient required for normal thyroid hormone production, allowing kelp to contribute nutritional support for normal thyroid function while complementary herbs in the formula address the product's broader joint and mobility wellness goals.

This comprehensive approach recognizes that maintaining an active lifestyle involves more than focusing on one area of the body.

Explore God's Way Herbs Skeletor Joint & Mobility Support

Is Kelp the Same as Seaweed?

Kelp is a type of seaweed, but not every seaweed is kelp.

Seaweeds are generally divided into three broad groups:

• Brown algae

• Red algae

• Green algae

Kelp belongs to the brown algae group.

Other familiar seaweeds—including nori, Irish moss, dulse, and various Gracilaria species—belong to different botanical classifications.

This distinction matters because different seaweeds can have dramatically different concentrations of iodine, minerals, polysaccharides, and other compounds.

Therefore, research involving one seaweed should not automatically be applied to another.

Kelp vs. Irish Moss

Kelp and Irish moss are also different.

Kelp refers primarily to large brown algae, particularly species within the order Laminariales.

Irish moss (Chondrus crispus) is a red seaweed.

Both can contain minerals and complex marine polysaccharides, but their chemical profiles differ.

Irish moss is particularly recognized for its carrageenan-type polysaccharides, while kelp is associated with compounds such as alginate, laminarin, fucoidan, and often substantial iodine concentrations.

Scientific Research on Kelp

Kelp research spans nutrition, endocrinology, marine biology, food science, polysaccharide chemistry, and natural-product research.

One of the clearest areas of human evidence involves iodine and thyroid physiology.

A controlled clinical study involving 36 healthy adults found that four weeks of kelp supplementation significantly increased urinary iodine and produced measurable changes in thyroid-stimulating hormone (TSH). The researchers concluded that additional research was needed to determine the consequences of long-term supplementation. (PubMed)

More broadly, researchers consistently recognize iodine as essential for thyroid hormone synthesis while warning that excessive intake can cause thyroid dysfunction in susceptible individuals. (PubMed)

Research also continues into kelp's other constituents, including alginates, laminarins, fucoidan, fucoxanthin, minerals, and other marine compounds. (PubMed)

Many of these studies involve isolated compounds, concentrated extracts, laboratory models, or animals.

This distinction is essential: discovering an interesting biological activity from an isolated kelp compound does not establish that consuming ordinary kelp produces the same effect in humans.

Is Kelp Safe?

Kelp's iodine content is both one of its most valuable nutritional characteristics and its most important safety consideration.

Excessive iodine intake can disrupt thyroid function.

Scientific literature documents that excessive iodine exposure may contribute to hypothyroidism or hyperthyroidism, particularly among susceptible individuals. (PubMed)

Clinical reports have also documented thyroid dysfunction associated with kelp-containing supplements and preparations. (PubMed)

People with existing thyroid disorders should be particularly cautious about adding concentrated kelp or iodine supplements without discussing them with their healthcare provider.

People who are pregnant or breastfeeding, taking thyroid medication or other prescription medications, or managing a medical condition should also seek appropriate professional guidance before using concentrated kelp supplements.

The goal with iodine is adequacy—not excess.

Explore Herbal Wellness with God's Way Herbs

Kelp demonstrates that nature's wellness ingredients aren't limited to plants growing on land. From traditional herbs and roots to mineral-rich marine botanicals, different natural ingredients can contribute unique nutritional and botanical properties to thoughtfully designed formulas.

God's Way Herbs brings together carefully selected organic and wildcrafted botanicals in herbal formulas created to complement a wide range of everyday wellness goals.

Whether you're exploring botanicals for joint and mobility wellness, thyroid nutritional support, cardiovascular wellness, cognitive health, digestion, immune support, adaptogenic wellness, natural energy, reproductive wellness, cleansing, or everyday vitality, discover formulas designed to make traditional herbal wellness practical for modern lifestyles.

Shop All God's Way Herbs Herbal Supplements & Wellness Products

For plant-inspired wellness beyond supplements, discover natural options for bathing, moisturizing, grooming, and everyday personal care.

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References & Further Reading

NIH Office of Dietary Supplements — Iodine Fact Sheet

PubMed — Iodine, Seaweed and the Thyroid

PubMed — Effects of Kelp Supplementation on Thyroid Function

PubMed — Human Exposure to Iodine from Edible Seaweeds

PubMed — Kelp (Laminaria): Physical, Chemical and Biological Properties

PubMed — Excess Iodine Intake and Effects on Thyroid Function

PubMed — Seaweed Consumption, Iodine Nutrition and Thyroid Function: 2026 Human Study

Educational Disclaimer: This information is provided for educational purposes only and is not intended to diagnose, treat, cure, or prevent any disease. Kelp can contain substantial and highly variable amounts of iodine. While iodine is essential for normal thyroid hormone production, excessive intake can adversely affect thyroid function. Consult a qualified healthcare professional before using concentrated kelp or iodine supplements, particularly if you have a thyroid condition, take thyroid medication, are pregnant or breastfeeding, or are managing another medical condition.