How Seaweed and Kelp Affect Your Thyroid

It’s important to recognize that the high doses of iodine in kelp supplements and other dietary sources can throw your thyroid out of whack even if you don’t currently have thyroid issues. « Excess iodine can … lead to too much thyroid hormone production, causing hyperthyroidism, » warns the Harvard T.H. Chan School of Public Health (HSPH). « Sometimes even just a slight increase in dietary iodine above the RDA can cause iodine-induced hyperthyroidism in sensitive individuals. » Following the escape from the acute Wolff-Chaikoff effect, the biosynthesis of NIS can be shut down by a TSH-independent mechanism. D)Two cases of reversible hypothyroidism were reported in patients ingesting seaweed (kelp) daily containing 25.4 mg and 43.1 mg iodine, along with 2 cases of irreversible hypothyroidism in patients ingesting seaweed daily containing 15 mg and 20 mg iodine.

• After 3 months of antithyroid therapy and without the consumption of kelp – containing tablets, normal thyroid function was regained.
• As iodine is not produced in the body, daily intake is required from external sources.
• If you suspect you have a thyroid disorder, visit your doctor to have it definitively diagnosed.
• The predominant effect of kelp seems to be inhibition of release of thyroid hormones, although reports of hyperthyroidism have also been reported.
• Savory dishes can be made with kelp noodles, puree, whole fresh leaves, flakes and seasonings.
• In this case report, the consumption of sea kelp and consequent excessive daily intake of iodine proved to negatively impact the patient’s thyroid function, resulting in overt hypothyroidism.

1. Patient information

Kelp is a type of brown seaweed and is often found in dense, fixed areas called kelp beds or kelp forests. The patient’s symptoms are consistent with hypothyroidism but also overlap with her history of PTSD and fibromyalgia. During the appointment, her clinical observations are unremarkable, with normal oxygen saturation, pulse rate and blood pressure within normal limits and afebrile. The modest thyroid pain at palpation could suggest the occurrence of a subacute thyroiditis. However, thyroid pain at palpation is compatible with the fast thyroid enlargement. The ultrasound feature of ‘thyroid inferno’ is not typical of subacute thyroiditis, while it has been documented to occur after an excessive iodine load.

Table 2.

Further analysis revealed normal thyroid function, so the hyperthyroidism reversed completely. « Both hyperthyroidism and hypothyroidism have been linked to too much kelp intake, » note researchers at the University of Rochester Medical Center. « This is due to its high amount of iodine. Abnormal thyroid function has also been linked directly to too much use of kelp supplements. »

During the SMR, the pharmacist explained to the patient that weight loss would be a struggle with uncontrolled hypothyroidism. She was advised to continue with the same dosage of levothyroxine and to have a repeat thyroid profile in 8–12 weeks (although it had to take place in 16 weeks because the patient had travel plans). We have described a case of transient hyperthyroidism following the ingestion of kelp-containing tablets.

• Within 3 months of iodide restriction, serum T4 level and TSH level normalized .
• Many vulnerable groups where iodine requirement is increased such as pregnant mothers, their infants, vegans, or women of childbearing age continue to show deficits in iodine intake despite the availability of iodized salt 6, 7.
• Dissolving Konbucha is not so difficult and does not need to be heated (whenheated, iodine is volatilized.).
• Your years of avoiding iodized salt may have resulted in an inadequate iodine intake for you, though.
• Iodine vapour condenses to form nuclear clusters which can coalesce to produce new particles leading to aerosol and cloud formation affecting climate change 11.

If you are taking this drug combination, it is very important to be under close medical supervision to minimize severe side effects and ensure your safety. UIC was a good indicator of their iodine status.Powdered kelp was effective for recovery and safe treatment for HID. Before the investigation, informed consent for thyroid function test and UIC measurement was obtained from allfamily members of the seven patients, according to Helsinki declaration.

An excess of iodine can also lead to Grave’s disease, thyroid cancer and toxic levels of thyroid hormones. Symptoms of iodine poisoning include abdominal pain, diarrhea, fever, lack of urination, seizures, shortness of breath, thirst and vomiting, per the HSPH. Iodine is an essential trace mineral; the body can’t produce it, so it has to come from your diet. Iodine isn’t the only culprit when it comes to toxicity, overdose, interactions and other adverse side effects of kelp supplements. It is commonly enjoyed sautéed, in salads or as a dried snack, and is also available as a dietary supplement that is often marketed as being good for the thyroid.

« Even a small systematic increase in iodine supply can significantly increase the risk of thyroid disease. … The mechanism through which seaweed synthroid cranberry or high iodine levels might promote thyroid cancer remains unclear. » When it comes to eating kelp or taking kelp supplements, the iodine level that could cause overdose varies from person to person, depending on individual physiological factors and how much iodine is consumed via other iodine sources such as iodized salt. When we started powdered kelp at 1.6–2 g/d in 2 cases, their UICs were too high (1,380 µg/l in case 4, 560 µg/lin case 5, not presenting in Table 2).

Failure to achieve a satisfactory weight loss may induce the hypothyroid participants to persist or even increase the consumption of the iodine-rich diet with the following worsening of the negative metabolic effects. Thyroid disorders arising from excess iodine intake including seaweed consumption can take the form of goitre, thyroid autoimmunity, hypothyroidism, or hyperthyroidism 8, 9, 40, 41, 42. Patients with autonomously functioning nodules perhaps arising from a previous iodine deficiency state can develop a form of hyperthyroidism termed Jod-Basedow arising from excess iodine intake 8. Some authors have suggested that excessive seaweed consumption may itself result in chronic lymphocytic thyroiditis 43.

Iodine is an essential micronutrient which is crucial for normal thyroid function. When iodine intake fallsbelow the recommended level, the thyroid may not synthesize sufficient amounts of thyroid hormone. Worldwide,about 30% of the population, which is about 1,900 million people, has an inadequate iodine intake (1). ICCIDD recommended that iodizedsalt should contain 20–40 mg/kg (20–40 µg/g) of iodine in order to provide 150 µg/day of iodine, the recommendeddaily intake for an adult.

In cases of reversible hypothyroidism, restricting dietary intake of seaweed resulted in normalization of thyroid function . Q. When my internist noted a low-normal thyroid value, he suggested a thyroid supplement. Two 100 mg tablets a day brought the thyroid value up to normal and warmed my cold toes. Sea kelp is the name given to the collection of brown seaweed species Laminariales​6​. Owing to their iodine content, kelp formulations are promoted as a way to manage thyroid deficiency and promote weight loss​7​. Herbal supplements are often considered safe by the public as they are thought to be ‘natural’, but they can interact with other medicines​8​.