234 %
Selenium contributes to the normal function of the immune system, to normal thyroid function and to the maintenance of normal hair and nails.
How many calories are in baked tuna?
190kcal
in a 140 g fillet
136 kcal per 100 g.
Source: UK CoFID 2021, record 16-400, 9 analysed samples. Checked 5 October 2026.
1.1 gFat
45.2 gProtein
0 gFibre
234 %Daily selenium
What’s in a 140 g fillet
More than half of a fillet is water, which is why the calories stay low. What is left is mostly protein.
- 1.1 gFat
- 45.2 gProtein
- 95.5 gWater
About average for fish and seafood
Tuna is 136 kcal per 100 g. The 170 fish and seafood in this database average 138.
Tuna136
Fish and seafood average138
Low in sugar and salt
Low sugars and low salt by UK labelling rules, per 100 g.
Sugars, per fillet0 g
Salt, per fillet0.22 g
Vitamins and minerals in tuna
Five of the 22 reach the “high in” level, led by selenium.
A source of
Only a trace
- Vitamin C
Show all 22 with amounts
Selenium0.129 mg, 234 %
Niacin (vitamin B3)34.9 mg, 218 %
Vitamin B120.00308 mg, 123 %
Vitamin D0.00434 mg, 87 %
Phosphorus406 mg, 58 %
Potassium630 mg, 32 %
Vitamin B60.32 mg, 23 %
Chloride182 mg, 23 %
Iodine0.0322 mg, 21 %
Magnesium57.4 mg, 15 %
Thiamin (vitamin B1)0.17 mg, 15 %
Vitamin A0.109 mg, 14 %
Iron1.3 mg, 9.3 %
Biotin0.00406 mg, 8.1 %
Riboflavin (vitamin B2)0.1 mg, 7 %
Zinc0.7 mg, 7 %
Pantothenic acid (vitamin B5)0.29 mg, 4.9 %
Copper0.04 mg, 4.2 %
Folate0.007 mg, 3.5 %
Calcium15.4 mg, 1.9 %
Vitamin E0.18 mg, 1.5 %
Manganese0.01 mg, 0.7 %
Badges use the UK legal thresholds per 100 g: 15 % of the reference intake for “source of”, 30 % for “high in”. A trace is shown as “trace” and never counts.
What tuna doesn’t give you. And where to find it.
No recorded vitamin C, and only 1.1 % of the vitamin E reference intake and 2.5 % of the folate reference intake per 100 g.
Vitamin C
Tracein tuna
Find it inCherries, West Indian2150 % per 100 g
Vitamin E
1.1%in tuna, per 100 g
Find it inSunflower seeds, toasted326 % per 100 g
Folate
2.5%in tuna, per 100 g
Find it inLiver, chicken, fried675 % per 100 g
100 mgVitamin C, 125 %
0.075 mgSelenium, 136 %
0.00125 mgVitamin D, 25 %
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Tuna against other fish and seafood
Per 100 g, tuna has the most selenium of the 6 here, ahead of mullet (Grey, grilled).
0.092mg
0.066mg
0.046mg
0.041mg
0.036mg
0.033mg
Tuna, flesh only, bakedthis page
Mullet, Grey, grilled−0.026 mg
Shrimps, boiled−0.046 mg
Plaice, steamed−0.051 mg
Red snapper, fried−0.056 mg
Coley, raw−0.059 mg
All values per 100 g, from the same dataset. Differences are against tuna.
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Questions about tuna
The questions people ask about tuna, answered from the dataset.
How many calories are in a portion of tuna?
A typical portion (140 g, one fillet) gives 190 kcal. Per 100 g the figure is 136 kcal.
Is tuna high in selenium?
Yes. Tuna, flesh only, baked has 0.092 mg selenium per 100 g, 167 % of the NRV, above the 30 % threshold for a “high in” claim.
Does baking change the vitamin B6 in tuna?
Yes. Per 100 g, vitamin B6 goes from 0.43 mg raw to 0.23 mg baked. Part of that is the vitamin or mineral itself changing, part is the change in water content.
Which vitamins and minerals does tuna have most of?
By share of the daily reference intake: selenium (0.092 mg, 167 %), niacin (24.9 mg, 156 %) and vitamin B12 (0.0022 mg, 88 %) per 100 g.
How these numbers were made
Every figure comes from the UK Composition of Foods Integrated Dataset (CoFID), 2021 edition, record 16-400, Tuna, flesh only, baked, 9 analysed samples, published by Public Health England under the Open Government Licence v3.0. Main data references: DH, Nutrient analysis of fish and fish products, 2013. Values are per 100 g of the edible part; a fillet is 140 g, one fillet, the usual UK portion for fish and seafood. Edible proportion: 76 % of the weight as bought is eaten. Reference intakes follow Regulation (EU) 1169/2011 Annex XIII as retained in GB law; “source of”, “high in” and “low” follow Regulation (EC) 1924/2006, assessed per 100 g. Function lines are the authorised wording from the GB register of nutrition and health claims, credited to the nutrient. Energy is rounded to the whole kcal and kJ; other amounts to one decimal, or two below 1. A trace is shown as “trace” and never gets a figure or a badge; a nutrient never analysed is left off the page. We start from the dataset’s 2,887 records and keep 2,322: records weighed with bone, shell or skin, alcoholic drinks, infant foods, brand-named products, records with fewer than eight measured vitamins and minerals and near-identical variants are left out. Group context uses the 170 fish and seafood kept from the dataset; a rank counts only the foods with a measured figure for that nutrient. Food images are illustrations from Ingredient Atlas, released under CC0; they show the food, not the measured sample, and where no illustration of the exact food exists the nearest one is shown (here: Tuna). Checked 5 October 2026. Contains public sector information licensed under the Open Government Licence v3.0.
More fish and seafood
From the same group, with calories per 100 g, and the foods with the most selenium.
More fish and seafood
- Kippers, grilled245 kcal
- Pangasius, poached102 kcal
- Rohu, raw79 kcal
- Skate, grilled79 kcal
- Winkles, boiled72 kcal
- Cod, in batter, fried, takeaway240 kcal
- All 170 fish and seafood
Most selenium
- Crab, brown meat, purchased cooked0.225 mg
- Shrimps, dried0.17 mg
- Prawns, standard, dried0.163 mg
- Kidney, pig, fried0.27 mg
- Brazil nuts, kernel only0.254 mg
- Kidney, pig, stewed0.25 mg
- Selenium guide