Selenium is a trace mineral your body uses to build selenoproteins, the proteins that run thyroid hormone metabolism and your antioxidant defences. Adults need about 55 micrograms a day, and an Australian supplement that carries selenium caps the daily dose at 150 micrograms. Food covers most of that for most people. A daily formula covers the gap, and the two things worth checking before you buy one are the form and the number on the label.
TL;DR
- Selenium supports thyroid hormone metabolism and antioxidant defences. Those two functions are why it's in the formula, and they're the ones worth holding onto.
- The adult reference intake is 55 micrograms a day. The daily cap for selenium from supplements is 150 micrograms, and it covers everything you take in a day.
- Selenomethionine is the form plants build and the form food delivers. It's the form in our scoop, at 150 micrograms of selenomethionine per 10 g serve, providing 60 micrograms of selenium.
- Selenium and iodine work as a pair in the thyroid, so we dose them together.
- Every quantity in a listed medicine is on the public ARTG register. AUST L 508472 is a two minute check.
What does selenium do in the body?
Selenium supports thyroid hormone metabolism and your antioxidant defences, and both jobs come down to one family of proteins.
Your body doesn't use selenium as a loose mineral. It builds it into selenoproteins, about 25 of them in humans . Two matter for everyday energy. The thyroid holds more selenium than any other organ in the body, and selenium-containing enzymes convert the stored form of thyroid hormone (T4) into the active form (T3) . The other job is defence: enzymes such as glutathione peroxidase use selenium to break down peroxides, the by-products of normal metabolism that damage cells when they build up .
Selenium and iodine work as a pair here. Iodine is a component of thyroid hormone itself, and selenium supports thyroid hormone metabolism. Both minerals are needed in adequate amounts, and too much of one can contribute to a deficiency of the other . That's why 200 micrograms of iodine from potassium iodide sits next to the selenium in our scoop. Keeping the pair in one place is simpler than tracking two bottles, and simpler still than getting one side of the pair wrong.
How much selenium do you need each day?
Adults need about 55 micrograms of selenium a day, and the cap for selenium from supplements is 150 micrograms.
The 55 microgram figure is the US Recommended Dietary Allowance, the same for adult men and women aged 19 and up . Other authorities land close by. The World Health Organization suggests 26 to 34 micrograms a day based on enzyme activity, while the German, Austrian and Swiss nutrition societies revised their reference values up to 60 to 70 micrograms . Deficiency is generally defined as an intake under 40 micrograms a day .
The 150 microgram line is the Australian one, and the label carries it for a reason. Selenium is toxic in high doses, so the daily dose from supplements is capped at 150 micrograms, and the label states that number as the limit it enforces.
What counts toward that cap is everything you swallow in supplement form, not just the selenium tablet: a multivitamin, a mineral blend and a scoop of a formula all spend from the same 150 micrograms.
Food sits in a wider frame. The average adult intake in the United States is about 108 micrograms a day from food and drink, and the tolerable upper level there is 400 micrograms from all sources . In 2023 the European Food Safety Authority set its adult upper limit at 255 micrograms a day from every source . A daily habit of Brazil nuts can move you a long way up that range on its own, which is worth knowing before you stack a supplement on top of it.
Our formula carries 60 micrograms of selenium in one 10 g scoop, from 150 micrograms of selenomethionine, well inside the 150 microgram cap. There's no half serve and no double serve to work out. One scoop is the day.
What are the signs of selenium deficiency?
Selenium deficiency is uncommon in Australia, and it rarely announces itself, which is why a symptom hunt is the wrong way to look for it.
Places with a broad food supply see very little of it. Harvard's Nutrition Source puts the rarity down to selenium-rich soils and the way food moves between regions . The pattern that does show up is dietary, not symptomatic. People who eat mostly plant foods, and especially those whose food is grown in low-selenium soil, tend to take in less . Selenium in plants depends on the soil the crop grew in, and that varies widely: under 0.1 mg per kg in parts of Finland and Scotland, up to around 3 mg per kg in seleniferous regions .
So the practical check is a diet question. If most of your protein comes from plants grown in one region, or you've cut out whole food groups, selenium is one of the minerals worth checking rather than assuming. A health professional can measure your selenium status directly instead of guessing from how you feel.
Who should not use selenium?
Selenium products in Australia are labelled for adults, and the label sets out the groups it rules out. Check that list against your own situation before the first scoop; if you're unsure where you sit on it, a pharmacist can settle it in a minute.
Two other groups need care. If you already take a multivitamin, a stand-alone selenium tablet or another mineral product, add the selenium numbers up before you add a third. The 150 microgram cap is a total for the day, not an allowance per product. And if you take a regular medicine, ask your health professional or pharmacist first. The NIH fact sheet notes that selenium can interact with some medicines , and a pharmacist can check your list faster than you can read every label on the shelf.
What food is highest in selenium?
Brazil nuts are the highest food source of selenium by a wide margin: one ounce, about six to eight nuts, carries 544 micrograms, which is 989% of the daily value .
| Food, as published | Selenium per serve |
|---|---|
| Brazil nuts, 1 ounce (6-8 nuts) | 544 mcg |
| Tuna, yellowfin, cooked, 3 ounces | 92 mcg |
| Sardines, canned in oil, 3 ounces | 45 mcg |
| Shrimp, cooked, 3 ounces | 42 mcg |
| Beef steak, 3 ounces | 37 mcg |
| Cottage cheese, 1 cup | 20 mcg |
| Egg, hard-boiled, 1 large | 15 mcg |
| Oatmeal, cooked, 1 cup | 13 mcg |
| Mushrooms, portabella, grilled, half a cup | 13 mcg |
| Whole-wheat bread, 1 slice | 8 mcg |
Seafood, meat and eggs are the reliable sources, because selenium travels with protein. The oat, bread and mushroom numbers show why plant sources are unpredictable: they carry whatever the soil gave the crop . Brazil nuts are the swing the other way. The same nut can carry vastly different amounts depending on where it grew, with samples ranging from 0.03 to 512 micrograms per gram .
Even one Brazil nut can hold more than the daily recommendation . A couple of nuts covers most adults, and a handful a day plus a supplement carrying its own selenium is how people move past the upper range without meaning to. On the food side, the published view is consistent. News-Medical's review puts it plainly: "Achieving optimal selenium status is safest through food-based sources, including Brazil nuts, seafood, meats, eggs, and whole grains, rather than high-dose supplements" . Food first, a formula for the gap, and only for an intake that needs topping up.
What are the benefits of taking selenium?
The benefit is coverage. Selenium supports thyroid hormone metabolism and antioxidant defences, and a formula earns its place when your diet isn't delivering the amount your body needs.
The bigger claims you'll see elsewhere deserve a straight answer. Trials that gave extra selenium to people who already had enough have largely found no change in the outcomes they measured . Harvard's Nutrition Source states it directly: if a person isn't at risk of a shortage, there's no evidence that a higher amount delivers the health benefits printed on supplement labels . The NIH fact sheet adds the mechanism detail: supplementation doesn't lift selenoprotein P or glutathione peroxidase activity unless selenium status is low to begin with .
So the case for selenium in a daily formula is narrow and worth stating plainly. It covers a mineral that Australian soils and Australian diets deliver unevenly. It supports two functions a label is allowed to name. And it does that work at a dose you can check. A number on a label is a fact about the product, not a promise about you: the scoop carries 60 micrograms of selenium, listed with its form on the register. What it does from there depends on what your diet was already providing.
Selenomethionine, and where it sits in a daily formula
Selenomethionine is the form of selenium that plants build and food delivers, and it's the form we use in the scoop.
The short version of the chemistry: in soil, selenium sits in inorganic forms such as selenite and selenate. Plants take those up and rebuild them into organic forms, mostly selenomethionine and selenocysteine . Brazil nuts store it as selenomethionine . So the form your body is used to handling from food is the same form a well-built formula delivers.
Supplement shelves carry four common forms: selenomethionine, selenium-enriched yeast (which is mostly selenomethionine grown into yeast), sodium selenite and sodium selenate . Your body absorbs up to about 90% of the selenium from all of them . What separates products is the number on the panel and whether the maker is willing to print it. A blend name tells you nothing; a quantity tells you what the daily cap allows.
We use selenomethionine at 15 micrograms per gram, which lands at 150 micrograms in the 10 g scoop and provides 60 micrograms of selenium. That sits well inside the daily cap, in the food form, inside a formula where every active is listed with its quantity. Ten grams, one scoop, one glass of cold water, each morning. If you want to see the whole build, the Hoola Daily Multivitamin page lists every ingredient and its dose, and the selenium collection covers the mineral on its own.
How can you check the selenium in a product?
You can check any selenium product in Australia in about two minutes, using the label and the public register. It comes down to three checks.
- Find the number, not just the ingredient. "Selenium" on a panel tells you nothing about dose. A disclosed quantity, in micrograms per serve, tells you everything the label can: how much you're taking and how close you are to the 150 microgram cap. If the selenium sits inside a proprietary blend with no number next to it, that silence is your answer about the product.
- Look up the listing number. Every listed medicine in Australia carries an AUST L number, and the public ARTG register shows the ingredients and quantities behind it. Ours is AUST L 508472, and how our ARTG listing works walks through what a register entry does and doesn't say. The short version: it records what's in the product so you can compare it with the label. Our regulatory compliance page keeps the rest of the paperwork in the open.
- Add up the day. Selenium from supplements shares one budget, so your multivitamin, your stand-alone tablets and your scoop all draw on the same 150 micrograms. If a second product carries selenium, you've already spent part of the cap before you start.
Do those three checks and you'll know more about the product than most of the pages you'll read about it. Our numbers sit on the register and on the pouch: 150 micrograms of selenomethionine per 10 g scoop, providing 60 micrograms of selenium, one scoop a day. The 150 g pouch runs 15 days at $65, the subscription works out to $99 a month, and everything else in the blend is listed with its dose. Try the 150 g pouch and check the numbers for yourself.
Frequently asked questions
How much selenium is in Hoola?
One 10 g scoop carries 150 micrograms of selenomethionine, which is 0.15 mg, and it provides 60 micrograms of selenium, well inside the 150 microgram daily cap for supplements. That's the form food delivers, and it goes down as one scoop in the morning. The quantity sits on the ARTG register under AUST L 508472 beside the other 26 actives, and on the Hoola Daily Multivitamin page, so you can read it before you buy anything.
Can you take selenium with iodine?
Yes, and the two work as a pair in the thyroid. Selenium supports thyroid hormone metabolism, while iodine is a component of the hormone itself . Harvard's Nutrition Source makes the relationship plain: both minerals are needed in adequate amounts, and too much of one can contribute to a deficiency of the other . We carry 200 micrograms of iodine from potassium iodide alongside the selenium, in the same scoop.
Is a blood test the only way to know your selenium level?
It's the usual way. The NIH fact sheet describes plasma and serum selenium concentrations as the standard measure, with whole blood and hair or nail samples used to read longer-term status . A supplement label can't tell you your level and neither can a symptom list. Status is measured, not felt, so if you want to know where you sit, that's a question for your health professional.
What does AUST L 508472 mean?
It's the listing number for Hoola on the Australian Register of Therapeutic Goods. A listing is where the ingredients and their quantities are recorded, which is why you can check every number in our formula against a public register rather than taking the pouch's word for it. It records what's in the product and that it meets the listing requirements. It isn't a statement that the product works, and no honest supplement page will tell you otherwise.
