Cell protection
Selenium contributes to protecting cells from oxidative stress.
Selenium: A Small but Essential Mineral
How selenium supports cells and thyroid function, where it is found and why more is not always better.
Educational guide · Reviewed 26 July 2026What is selenium and why does the body need it?
Selenium is a trace mineral used in antioxidant systems, thyroid-hormone metabolism and DNA production.
Selenium
Food source · amount · everyday role
What it does for the body.
Thyroid function
It contributes to normal thyroid function.
Immune function
Selenium supports the normal function of the immune system.
When to pay particular attention
Needs are not identical.
Age, life stage, activity and the rest of the diet can change what deserves attention.
- People whose diets contain few selenium sources
- People following very restricted diets
- Anyone considering high-dose supplements — excess selenium can be harmful
Food first.
Fish, seafood, meat, eggs, dairy, grains and Brazil nuts contain selenium. The amount in plant foods varies with the soil.
How do we measure it?
One value. Three useful views.
Per 100 g
A standard basis for comparing different foods and pack sizes.
Per serving
The quantity associated with a stated serving. Serving sizes can differ.
Per package
The calculated total when the entire package is the relevant amount.
We show where every number comes from.
Diplomats Product Nutrition
The value belongs to the exact product, recipe and measurement basis shown. We present it as the product’s number.
Reference Nutrition Data
A scientific food database provides a range for a comparable fish. We mark it with an asterisk and never present it as a laboratory result for the product.
Nutrition Knowledge
Primary health and food-science sources explain what a nutrient does, who should pay attention and how the number is used.
What is selenium and why does the body need it?
Selenium is a trace mineral used in antioxidant systems, thyroid-hormone metabolism and DNA production.
Why does selenium: a small but essential mineral matter?
Cell protection: Selenium contributes to protecting cells from oxidative stress. Thyroid function: It contributes to normal thyroid function. Immune function: Selenium supports the normal function of the immune system.
Can a value be assumed from the fish species?
No. Diplomats separates general food education from facts verified for a particular recipe, serving and product.
What does “per 100 g” mean?
It is a standard comparison basis. It lets visitors compare products of different pack and serving sizes using the same amount of food.
How are products recommended?
The Product Finder combines product nutrition, flavour, format and the preferences you select to find the closest match.
Primary health and food-safety sources used to review this guide.
Apply the knowledge.
Compare product nutrition on the same per 100 g basis and choose what suits your meal.
Compare product nutritionPut it on the table.
Explore serving ideas and practical meal contexts connected to Diplomats products.
Explore recipesSee the knowledge in practice.
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