The best time to take thyroid minerals and fatty acids

They’re essential for a healthy thyroid—but do you know how much and when should you take them?

by Dr. Vedrana Högqvist Tabor

Photo: Laurynas Mereckas/Unsplash. Design: Clár Tillekens.

Photo: Laurynas Mereckas/Unsplash. Design: Clár Tillekens.

Supplements can be helpful if taken in the right dose and during the right time of the day, working together to help your thyroid.

But they can also disrupt each others’ functions or affect your medication. It’s important to keep this in mind when planning your daily supplement and medication taking.

Four supplements that can be great for your thyroid are:


Iodine is the most well-known known mineral for thyroid health. It is essential for the thyroid to build T4 and T3 hormones (1).

But to be beneficial for the thyroid, iodine needs to be well balanced, as too much of it can cause hypothyroidism (2, 3). Going over the daily recommended dose of 150 micrograms (or 220 micrograms during pregnancy) is usually not advised by health care practitioners (4).

The main food sources of iodine are:

  • Seafood (seaweed, scallops, cod, salmon, sardines, tuna)

  • Dairy and eggs (cow milk, yogurt, eggs)

  • Fruits (cranberries and strawberries)

A lack of iodine in the diet will have some negative effects: reduced muscle strength, heart, liver, kidney, and brain function. However, it’s not good to take too much iodine either.

Researchers have found that even a small increase in consuming iodine can trigger Hashimoto’s (5). It is not yet explained why this occurs; possibly an excess of iodine disrupts the balance of the immune system and changes its function from protecting the body to attacking one’s own organs (6, 7).

Iodine can synergize with Tapazole, a medication used to treat an overactive thyroid, and can cause an underactive thyroid (8).

Taking iodine with medicine used to treat high blood pressure, such as Lotensin, Prinivil, Zestril, and Monopril, or certain diuretics such as Aldactone and Midamor, can increase the risk of high blood potassium levels, leading to abnormal heartbeat/rhythm (8).

Omega 3

Omega-3 fatty acids have beneficial health effects, and are shown to help with several chronic conditions, including: lowering the risk of heart-related diseases (9,10); certain cancer types (11–14–8); rheumatoid arthritis, IBS, lupus, and multiple sclerosis (15, 16).

The main food sources of omega 3 are:

  • Walnuts

  • Flax seeds

  • Fatty fish (salmon and sardines)

A deficiency of omega-3 amino acids can cause skin problems like rough, scaly skin as well as a red, swollen, and itchy rash (9). An overdose of omega-3 may cause an unpleasant taste in the mouth and bad breath, nausea, bloating, heartburn, diarrhea, bleeding, and headaches.

Omega-3 can synergize with the blood thinner Coumadin and decrease the number of platelets in the blood, prolonging blood clotting times.


Selenium has multiple functions. It reduces inflammation, boosts thyroid hormone production, and is also an antioxidant (17–21).

The recommended daily dose is 55 micrograms (4).

The main food sources of selenium are (22):

  • Brazil nuts and sunflower seeds

  • Oysters and tuna

  • Whole wheat bread, rye, and mushrooms

  • Most meat

A selenium overdose might block the production of thyroid hormones, and cause anorexia, diarrhea, depression, and bleeding, as well as problems with breathing (23, 24).

Selenium levels in the blood are lower in people undergoing Cisplatin chemotherapy (25, 26).


Zinc is important for the regulation of thyroid hormones and the immune system (27). It is also connected with hair health (28).

The main food sources of zinc are (29):

  • Oysters, lobster, and crab

  • Beef, pork, and chicken

  • Cashews and chickpeas

If zinc is taken together with antibiotics, such as Cipro, Achromycin, and Sumycin it will decrease the activity of both zinc and antibiotics (30, 31). Taking antibiotics either two hours before or four to six hours after taking zinc helps avoid this problem (32).

Zinc will also reduce the absorption of penicillamine, a medication used for treatment of rheumatoid arthritis (33).

Some diuretics, such as Hygroton, Esidrix, and HydroDIURIL, will remove zinc from the body, resulting in very low zinc levels (34).

When to take your supplements

Proper dosage of your supplements is important, but it’s not the only thing to remember. The timing of your dose has an equal impact on the benefit you will get from a supplement.

Why is that? Your body’s internal clock makes most metabolic and molecular processes happen at a specific time of your day. It’s like that every day, no matter if you’re awake or asleep (35–38). This is a highly synchronized process, and disrupting it can and will have consequences on the entire body (39–41).

Your immune system has its own internal clock too. According to research on rheumatoid arthritis, your immune system is the most active in the early hours of the morning (42).

Changing your circadian rhythm by traveling through the time zones or doing shift work can significantly impact how your immune system functions, and can cause an increase in inflammation (43–47).

Not only can the disrupted circadian rhythm change the immune system, but if there is an ongoing inflammation in the body, it can change the circadian rhythm, too (48).

How can you get back in balance? By knowing your own body and detecting patterns. BOOST Thyroid can help you discover these patterns faster, with tracking on a five-point intensity scale on a daily basis.

Best time for supplements varies individually

You might not know the best time to take your supplements until you test several different times of the day.

If there is a pattern to your flare-ups, it might be best to take supplements a couple of hours before you expect your flare-ups, or immediately after you feel them.

By changing the times you take your supplements, and then sticking to the specific time for a couple of weeks, you might discover a new health pattern.

You can daily track your symptoms and supplements with BOOST Thyroid app. You can enter your dose, too. The more you track, the better we can help you determine your circadian clock.


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