Many vegetable
oils had a very high such ratio. On
the other hand, fish oils had a low ratio,
often around one; i.e., there were often
as many (sometimes even more) saturated
than polyunsaturated fatty acids in
fish oils. Because of this fact in the early
period of research in this field, fish oils
were never used. In 1956, however, a
paper appeared (Bronte-Stewart et al.,
1956) which showed that fish oils were
as effective (and usually a great deal
more effective) than vegetable oils in
lowering serum cholesterol levels when
taken in the diet.