How to choose the best Omega-3 to buy?

In omega-3 supplements, the differences between products can be huge and often invisible at first glance. These are the most important features that indicate the quality of omega-3 fish oil:

👉 Amount of effective components:

The usual amount of active ingredients ranges between 250 to 300 mg EPA + DHA per capsule. The rest is practically without any real effect. Purified and multi-concentrated oils contain a higher amount of EPA and DHA per capsule.

👉 Presence of heavy metals

Due to pollution of the sea and fish, the presence of heavy metals in fish oil is a serious health problem. Try to find relevant evidence that the oil you want to buy has been tested for the presence of heavy metals by an independent laboratory. With analysis, safety is greater, and trust in the brand is exactly confirmed.

👉 Excessive oxidation of oil

Excessive oxidation of fish oil is a silent problem that is rarely talked about. Omega-3 fatty acids are very sensitive to light, heat and oxygen. Without proper processing and quality control, the oil can:

• oxidize (go rancid)
• lose potency
• develop an unpleasant taste and odor

Most products containing omega-3 fish oil do not list this information anywhere. The question of the actual quality of a product should not be tied only to the perception of a particular brand, but also to analytical proof of quality.

You have the right to wonder: how many manufacturers publish independent laboratory analyses of heavy metals, peroxide or totox index of the finished product?

Answer: Very few, or rather, almost none! Without independent testing, you cannot know whether a product contains heavy metals, whether the oil is really purified and how much it has oxidized. That's why the differences between the products are significant, even though they are hidden behind similar labels and marketing messages.

A pretty bottle is a bonus, but quality without proof is just marketing. That's why we conduct and publish chemical analyses for Grassberg Omega-3 Premium that confirm the brand's reputation and the quality of the product.

Where marketing ends, numbers begin

✅ High concentration of active ingredients per capsule

Grassberg Omega-3 Premium contains a multiple concentrate of molecularly distilled fish oil.

• 420 mg EPA •300 mg EPA

This means that you take a larger amount of active substances from omega-3 in a smaller number of capsules.

✅ Presence of heavy metals:

Grassberg omega-3 fish oils are regularly tested for the presence of heavy metals.

All measured parameters are several times below the maximum permissible concentrations (MPC), which confirms the high level of product purity. The analysis was performed in an independent Croatian laboratory.

✅ Freshness and degree of oxidation

The results of the analysis of Grasberg Omega-3 Premium 1200 mg, carried out in the independent laboratory JS Hamilton according to the ISO 6885:2016-04 and ISO 3960:2017-03 standards, show that it is an encapsulated oil of excellent quality and very low initial oxidation.

Peroxide value (PV) indicates the initial stage of oil oxidation, or how much the oil has already started to react with oxygen. According to industry guidelines (GOED), low values ​​indicate fresh, stable and high-quality omega-3 oil, while higher values ​​indicate the appearance of peroxides and signs of spoilage:

• PV < 3 meq O₂/kg → very fresh oil
• PV < 5 meq O₂/kg → acceptable (quality standard)
• PV > 5 meq O₂/kg → sign of initial oxidation

In the Grassberg Omega-3 Premium the peroxide value is 1.2, which indicates very fresh oil and minimal initial oxidation.

Anisidine value (AV) is a measure of secondary oxidation products (aldehydes). They are responsible for the unpleasant smell and taste of rancid oil. According to the same (GOED) guidelines, a lower number indicates fewer undesirable compounds.

• AV < 10 → excellent
• AV < 20 → very good to good
• AV > 20 → sign of more advanced oxidation

Applied to the analysis of Grassberg Omega-3 1200 mg Premium, this means that the oil is very fresh, with controlled secondary oxidation. The analysis from 2026 was carried out in an accredited, independent EU laboratory, performed on a finished product taken from our warehouse.

What does the Totox number tell us?

Totox (Total Oxidation) index is a number that shows the total oxidation of the oil, that is, it tells us how fresh or degraded the omega-3 oil is. Oxidized oil has a weaker effect, can be unpleasant to consume and does not provide the expected benefit. Totox Index = 2×Peroxide amount + Anisidine amount and according to the industry standard the index is interpreted as follows:

• Below ~10 = excellent quality*
• Below ~20 = very good to good
• Above ~25 = sign of poor quality, rancid

*These values ​​most often refer to freshly extracted oil that has not undergone the encapsulation and packaging process.

Oils with high Totox values ​​(close to or above 25) are considered oxidized, rancid oils of poor quality. They can be recognized by their unpleasant odor, intense fishy taste, and strong aftertaste in the mouth. Sound familiar?

Advice for taking omega-3

Omega-3 absorption depends on the secretion of bile, the activation of enzymes for fat digestion, the formation of micelles (transport "droplets" in the intestine) and other factors.

All of them are best activated with a proper meal, so even though omega-3 acids are fatty, it is best to take them with a complete meal that will improve the absorption and utilization of EPA and DHA.