What does the omega-3 number on a label mean?
A capsule labelled “1,000 mg fish oil” may not contain 1,000 mg of EPA and DHA. Find those amounts on the panel, check how many capsules make a serving, then compare the cost. The worked example below shows the calculation.
What does the large number measure?
A number is only useful when the label says what it measures. “1000 mg” may refer to all the oil in one capsule. It is not the same as 1000 mg of omega-3, EPA or DHA.
Turn to the information panel and note four details:
- Serving size: one capsule, two capsules or another amount.
- Total oil: the complete oil amount for that serving.
- EPA: the stated milligrams in the same serving.
- DHA: the stated milligrams in the same serving.
Read EPA and DHA as their own entries. If a label reports 180 mg EPA and 120 mg DHA per capsule, the combined figure is 300 mg. Nothing else in the capsule counts as EPA or DHA. This example explains the sum; it is not a suggested amount.
How do you match serving sizes?
Two front labels can look similar while their information panels use different serving sizes. One may give figures for a single capsule. Another may give them for two. Compare per capsule or per daily serving, but do not switch between the two halfway through.
A quick note keeps the arithmetic clear:
- Product A: DHA per serving ÷ capsules in that serving = DHA per capsule.
- Product B: DHA per serving ÷ capsules in that serving = DHA per capsule.
- If comparing combined omega-3, add EPA and DHA for each matching serving.
Give the source its own line too. An algal oil label may report DHA without EPA. A fish oil label may report both. That difference does not make the larger front number more informative. The useful comparison is the named amount you want, measured across an equal serving.
How do you calculate cost per 100 mg DHA?
Pack price alone cannot show the cost of a stated amount of DHA. First find the total DHA in the pack:
`DHA per capsule × number of capsules = total DHA in the pack`
Then calculate:
`pack price ÷ total DHA × 100 = cost per 100 mg of DHA`
For a worked example, take a S$30 pack of 30 capsules, with 200 mg DHA in each capsule. The pack contains 6,000 mg DHA. S$30 divided by 6,000, then multiplied by 100, gives S$0.50 per 100 mg DHA.
Repeat the same sum for the second product. Use the actual checkout price and capsule count. Add delivery charges before dividing if they differ. This method compares the declared DHA content and cost. It does not compare suitability, quality controls or any unstated feature.
What if the DHA amount is missing?
An ingredient list can identify where an oil or nutrient comes from. The information panel gives the declared amount. Both matter, but they answer different questions.
For algae-based products, look for the named algal source and a stated DHA quantity. If the panel gives no DHA figure, do not calculate one from the amount of an ingredient or blend. The missing number remains unknown. Ask the seller for the current label, and ask a doctor or pharmacist about personal use.
Product details: Vplus Formula: ingredients, pack details and directions.
Further reading: NIH guide to Omega3 fatty acids.
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