Well, the article abstract isn't consistent with the description you linked to. One of the dangers of paraphrasing science.
From the abstract: "Twelve healthy male volunteers (aged 53–65 yr) were assigned to consume an intake of successively 200, 400, 800, and 1600 mg/d DHA, as the only {omega}-3 fatty acid, for 2 wk each dose."
I don't know what inconsistency you noticed between the news article and the abstract, but it seems the abstract itself describes a study that is missing the control group that gets a dosage of 0.
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