Intake of unsaturated fatty acid is associated with:
Increased risk of cardiovascular disease
Decreased risk of cardiovascular disease
Increased risk of GI disturbances
Decreased risk of GI disturbances
Diets deﬁcient in fresh fruit, vegetables and polyunsaturated fatty acids are associated with an increased risk of cardiovascular disease. The introduction of a Mediterranean-style diet reduces cardiovascular events. However, dietary supplements, such as vitamins C and E, beta-carotene, folate and ﬁsh oils, do not reduce cardiovascular events and, in some cases, have been associated with harm.
Reference: : Davidson P R I N C I P L E S   and Practice O F M E D I C I N E 23rd edition page no  486