‘Why fish oils hold all-powerful key to healthy heart’ is the
headline in the Daily Express, which goes on to report, somewhat
over-enthusiastically, that ‘tens of thousands of lives a year
could be saved if people ate more fish’. These wildly optimistic
claims are actually based on an small experimental study
involving 59 people, looking whether our genetic makeup affects
how dietary fats can influence the way in which our blood
vessels constrict (narrow) and dilate (widen). The question of
whether eating fish gives us a healthy heart, or saves lives,
was not considered by the researchers. On two separate occasions
the participants were given either a drink high in saturated
fats, or a drink with some saturated fats combined with fish
oils. The researchers then used ultrasound to look at how their
subjects’ blood vessels dilatated again after being briefly
blocked by a blood pressure cuff. In general, the researchers
found that the response of the blood vessels varied: - according
to the drink given - betwee