Whiting: a lean white fish studied mostly through cod

A meta-analysis of 18 to 21 randomized trials with 1392 to 1456 participants found that eating lean fish lowered blood triglycerides compared with eating no fish. Total cholesterol and lipoproteins did not change. The abstract gives no size for the drop, and the trials covered lean fish in general. We found no trial on whiting itself, so the evidence here comes from lean fish in general and from cod, a close relative. Raw whiting has about 18.5 g protein per 3.5 oz (100 g) in both the US and UK tables, and 0.7 g fat in the UK record. The tables disagree on selenium, 32.1 mcg against 21 mcg, and only the UK one lists iodine, at 67 mcg. A regular US survey fillet of 90 g, as typically eaten, comes to about 210 calories with 11.9 g fat, because that recipe includes cooking fat.

The numbers, per 3.5 oz (100 g)

As people eat it, per 3.5 oz (100 g)

How much is actually in it

• US and UK tables agree on raw whiting protein at about 18.5 g per 3.5 oz (100 g) but differ on selenium, 32.1 vs 21 ug, and the UK table adds 67 ug iodine. — USDA SR Legacy FDC 173713 (Fish, whiting, mixed species, raw) vs CoFID 2021 16-159 (Whiting, flesh only, raw) (n = -) Evidence E source
  Protein 18.31 vs 18.7 g; selenium 32.1 vs 21 ug (35% apart); vitamin B12 2.3 ug (USDA); iodine 67 ug, fat 0.7 g, 81 calories (CoFID)

What a real portion looks like

• A regular whiting fillet in the US survey database weighs 3.2 oz (90 g) and, as typically eaten, gives about 210 calories and 14 g protein. — USDA FNDDS 2021-2023 food code 26157110, Fish, whiting, NFS (n = -) Evidence E source
  1 small/regular fillet 90 g: 210 calories, protein 14.3 g, fat 11.9 g, sodium 358 mg, selenium 24.8 ug; large fillet 135 g; whole fish 270 g

What your body absorbs

• In a 4-week randomized crossover trial in 20 adults, a lean-seafood diet raised median urinary iodine from 70 to 135 ug/L and also raised plasma selenium and arsenic. — 20 participants (7 males, 13 females), mean age 50.6, Norway, two 4-week periods (n = 20) Evidence B source
  Urinary iodine 70 to 135 ug/L (non-seafood 58 ug/L), P < 0.001; plasma selenium up (P = 0.001); urinary and plasma arsenic up (P < 0.001)

What cooking and storage change

• Baking lean fish without drippings keeps about 90% of vitamin B12 and all of its minerals, according to USDA retention tables. — USDA Retention Factors Release 6, Finfish and Shellfish Products, code 2301 (FINFISH,<5%FAT,BAKED,WO/DRIPPINGS) (n = -) Evidence E source
  Vitamin B12 90%, thiamin 90%, riboflavin 95%, niacin 95%; calcium, iron, zinc, sodium, potassium 100%

What it does to your health

• A meta-analysis of 18 to 21 randomized trials with about 1400 people found lean fish lowered blood triglycerides compared with no fish, with no change in cholesterol. — 18 to 21 crossover and parallel RCTs, 1392 to 1456 participants (n = 1456) Evidence A source
  Triacylglycerol lowered vs no fish; no significant change in total cholesterol or lipoproteins; size not given in abstract
• Observational data from five prospective studies link the highest lean fish intake with a 19% lower stroke risk. — 5 prospective cohort studies, 5 comparisons for lean fish (n = 5 studies) Evidence C source
  Lean fish RR 0.81 (95% CI 0.67 to 0.99); fatty fish RR 0.88 (0.74 to 1.04)

Safety, limits and interactions

• In a randomized trial in 137 pregnant women, eating 14 oz (400 g) of cod a week for 16 weeks did not raise the share exceeding the US EPA mercury reference dose. — pregnant women (n = 137), gestational week 20-36, Norway (n = 137) Evidence B source
  Hair mercury 554 vs 485 ug/kg (p = 0.186); 8% above EPA reference dose (6 intervention vs 4 control)
• The FDA lists whiting among its Best Choices fish and advises pregnant and breastfeeding people to eat 2 to 3 servings of 4 ounces a week from that list. — pregnant and breastfeeding people, parents of young children, US (n = -) Evidence E source
  Whiting in Best Choices (lowest mercury group); 2-3 servings per week, 1 serving = 4 ounces

Who this works differently for

• In a randomized trial in 133 pregnant women, eating 7.1 oz (200 g) of cod twice a week for 16 weeks did not change general infant development in the first year. — 133 pregnant women (19 weeks of gestation or less), 16 weeks, Norway (n = 133) Evidence B source
  Total ASQ-2 no difference (P = 0.633); ASQ:SE socio-emotional scores favored intervention (P = 0.020)

The bottom line

In a 4-week randomized crossover trial in 20 Norwegian adults, a lean seafood diet raised median urinary iodine from 70 to 135 mcg/L, against 58 mcg/L on the non-seafood diet. Plasma selenium went up too, and so did arsenic in blood and urine, which the study did not split into its forms. Observational data from five prospective studies link the highest lean fish intake with a 19 percent lower stroke risk (RR 0.81, 95% CI 0.67 to 0.99), an interval that only just clears no effect. Baking lean fish without its drippings keeps about 90 percent of vitamin B12 and all of the calcium, iron and zinc, according to USDA retention factors for lean fish as a group. For pregnancy, the FDA puts whiting on its Best Choices list, the lowest mercury group, and advises pregnant and breastfeeding people to eat 2 to 3 servings of 4 ounces a week from that list. In a randomized trial in 137 pregnant Norwegian women, 14 oz (400 g) of cod a week for 16 weeks left hair mercury at 554 against 485 mcg/kg in controls (p = 0.186). It did not raise the share of women above the US EPA reference dose. In another trial in 133 pregnant women, 7.1 oz (200 g) of cod twice a week for 16 weeks did not change overall infant development in the first year. A socio-emotional score from mothers' questionnaires favored the cod group in that secondary analysis. These are cod trials. We have no card on whiting and allergy or medicines.

Sources

1. whtg-r7-01 · reference dataset
   Fish, whiting, mixed species, raw (FDC 173713, SR Legacy): protein 18.31 g, selenium 32.1 µg, vitamin B12 2.3 µg per 100 g; Foundation samples 0; CoFID 16-159 Whiting, flesh only, raw: Protein (g) 18.7; Selenium (µg) 21; Iodine (µg) 67; Fat (g) 0.7; Energy (kcal) 81
   USDA FoodData Central SR Legacy and CoFID 2021, Public Health England, Open Government Licence v3.0 · checked 2026-10-02
2. whtg-r7-02 · reference dataset
   Fish, whiting, NFS (FNDDS 26157110, fdc_id 2706312): Energy 233 KCAL, Protein 15.84 G, Total lipid (fat) 13.17 G, Sodium 398 MG, Selenium 27.5 UG, Vitamin B-12 1.6 UG per 100 g; 1 small/regular fillet 90 g; 1 large fillet 135 g; 1 whole fish 270 g
   USDA FNDDS 2021-2023 · checked 2026-10-02
3. whtg-r7-05 · RCT
   UIC increased after 4 weeks of the lean-seafood intervention to 135 (110, 278) µg/L, but not after the non-seafood intervention [58 (33, 91) µg/L] (P diet-effect < 0.001). Fasting plasma Se increased in the lean-seafood intervention and decreased in the non-seafood intervention (P diet-effect = 0.001). Fasting urinary and plasma As increased in the lean-seafood intervention and was unchanged in the non-seafood intervention (P diet-effect < 0.001).
   Eur J Nutr, 2021 · checked 2026-10-02
4. whtg-r7-03 · reference dataset
   USDA-RETN-R6:2301 FINFISH,<5%FAT,BAKED,WO/DRIPPINGS: vitamin_b12_ug 90%; thiamin_mg 90%; riboflavin_mg 95%; niacin_mg 95%; calcium_mg 100%; iron_mg 100%; zinc_mg 100%; sodium_mg 100%
   USDA Table of Nutrient Retention Factors, Release 6 (2007), code 2301 · checked 2026-10-02
5. whtg-r7-04 · meta-analysis
   Meta-analysis of data from 18 to 21 eligible crossover and parallel-design RCTs with a total of 1392 to 1456 participants found triacylglycerol-lowering effects for lean fish compared with no fish consumption. Lean fish intake showed no significant differences related to total cholesterol or lipoprotein levels.
   Nutr Rev, 2021 · checked 2026-10-02
6. whtg-r7-08 · meta-analysis of cohorts
   Compared with the highest category of intake with lowest category, the summary relative risk was 0.88 [95% confidence interval (CI), 0.74-1.04] for fatty fish intake and 0.81 (95% CI, 0.67-0.99) for lean fish intake.
   Lipids Health Dis, 2018 · checked 2026-10-02
7. whtg-r7-06 · RCT
   Participants were randomly assigned to intervention (400 g of cod fillets per week) or control (continued habitual diet) groups for 16 weeks (gestational week 20-36). ... Post-intervention, the intervention group had median (inter-quartile range) THHg concentrations of 554 (392-805) µg/kg, and the control group 485 (341-740) µg/kg (p = 0.186). ... While the intervention with 400 g of cod per week slightly increased THHg concentrations, it did not lead to an increase in number of subjects exceeding the US EPA reference dose
   Environ Int, 2020 · checked 2026-10-02
8. whtg-r7-09 · agency advice
   Eat 2 to 3 servings a week from the "Best Choices" list ... 1 serving is 4 ounces ... Whiting
   US FDA and EPA, Advice about Eating Fish · checked 2026-10-02
9. whtg-r7-07 · RCT
   In an RCT, 133 pregnant women (≤19 weeks of gestation) were randomly assigned to receive 200 g cod fillet twice weekly (intervention) or to continue with their habitual diet (control) for 16 wk. ... We found no difference between infants in the intervention and control groups on total ASQ-2 scores (P = 0.633), but a difference on the ASQ:SE scores in favor of the intervention group
   J Nutr, 2021 · checked 2026-10-02