221 %
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 canned tuna?
223kcal
in a 140 g fillet
159 kcal per 100 g.
Source: UK CoFID 2021, record 16-417, 11 analysed samples. Checked 5 October 2026.
9 gFat
35.6 gProtein
0 gFibre
221 %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.
- 9 gFat
- 35.6 gProtein
- 93.9 gWater
- 1.5 gMinerals and the rest
Above average for fish and seafood
Tuna is 159 kcal per 100 g. The 170 fish and seafood in this database average 138.
Tuna159
Fish and seafood average138
Low in sugar
0 g of sugars per 100 g; the UK “low sugars” line is 5 g.
Sugars, per fillet0 g
Salt, per fillet1.3 g
Vitamins and minerals in tuna
Four of the 21 reach the “high in” level, led by selenium.
A source of
Only a trace
- Vitamin C
- Thiamin
Show all 21 with amounts
Selenium0.122 mg, 221 %
Vitamin B120.00476 mg, 190 %
Niacin (vitamin B3)23.1 mg, 144 %
Chloride854 mg, 107 %
Phosphorus286 mg, 41 %
Vitamin E4 mg, 33 %
Vitamin B60.43 mg, 31 %
Vitamin D0.00154 mg, 31 %
Potassium374 mg, 19 %
Magnesium49 mg, 13 %
Iron1.7 mg, 12 %
Zinc1.1 mg, 11 %
Iodine0.0168 mg, 11 %
Riboflavin (vitamin B2)0.15 mg, 11 %
Biotin0.00378 mg, 7.6 %
Copper0.07 mg, 7 %
Vitamin A0.0364 mg, 4.6 %
Pantothenic acid (vitamin B5)0.27 mg, 4.4 %
Folate0.0042 mg, 2.1 %
Calcium15.4 mg, 1.9 %
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 or thiamin, and only 1.5 % of the folate reference intake per 100 g.
Vitamin C
Tracein tuna
Find it inCherries, West Indian2150 % per 100 g
Thiamin (vitamin B1)
Tracein tuna
Find it inWheatgerm164 % per 100 g
Folate
1.5%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 %
Or one scoop of Immufix
Every 25 g scoop declares 100 mg of vitamin C, 0.00125 mg of vitamin D and 0.075 mg of selenium, alongside other vitamins and minerals. Vitamin C, vitamin D and selenium contribute to the normal function of the immune system.
30-day money-back on your first pouch. 75 kcal and 9.9 g of sugars a scoop.
Try your first pouch
30-day money-back guarantee on your first qualifying pouch, less £10 shipping and handling.
Tracked UK delivery
Free standard delivery to UK addresses. Royal Mail 48 tracked, usually 2 to 3 working days.
Made in Cambridgeshire
Made in the UK since 1998, with every nutrient and its declared amount listed on the label.
Tuna against other fish and seafood
Per 100 g, tuna has the most selenium of the 6 here, ahead of swordfish (grilled).
0.087mg
0.057mg
0.046mg
0.035mg
0.025mg
0.023mg
Tuna, canned in sunflower oil, drainedthis page
Swordfish, grilled−0.03 mg
Pollock, Alaskan, baked−0.041 mg
Plaice, raw−0.052 mg
Pangasius, poached−0.062 mg
Cod, raw−0.064 mg
All values per 100 g, from the same dataset. Differences are against tuna.
Since that first introduction in 1998, Immufix has remained a constant in my life.
Paula Radcliffe, ambassador and co-owner. Read her story
Taken every morning since 1998.
Paula Radcliffe has taken the same formula since she was 24. Customers rate Immufix 4.8 out of 5 from 89 reviews.
2:15:25World record, 2003
28Years, same routine
6London and New York wins
Review 1 of 3
Questions about tuna
What the numbers say to the questions people actually search.
How many calories are in a portion of tuna?
A typical portion (140 g, one fillet) gives 223 kcal. Per 100 g the figure is 159 kcal.
Is tuna high in selenium?
Yes. Tuna, canned in sunflower oil, drained has 0.087 mg selenium per 100 g, 158 % of the NRV, above the 30 % threshold for a “high in” claim.
Does cooking change the fat in tuna?
Yes. Per 100 g, fat goes from 0.7 g raw to 6.4 g canned. 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 (0.087 mg, 158 %), vitamin B12 (0.0034 mg, 136 %) and niacin (16.5 mg, 103 %) per 100 g.
How these numbers were made
Every figure comes from the UK Composition of Foods Integrated Dataset (CoFID), 2021 edition, record 16-417, Tuna, canned in sunflower oil, drained, 11 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: 62 % 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. 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
- Lemon sole, steamed95 kcal
- Plaice, raw76 kcal
- Salmon, smoked184 kcal
- Squid, dried313 kcal
- Bloater, grilled251 kcal
- Coley, poached114 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