The advisory committee further states:
Trans fatty acids also tend to lower a protective form of serum
cholesterol (HDL-cholesterol). Prospective epidemiological studies
further note that higher intakes of trans fatty acids are associated
with a higher incidence of coronary heart disease. (Ref. 88, p. 37).
Recent guidelines from the National Cholesterol Education Program
(NCEP) (Ref. 89) provide an update to the 1993 NCEP report (Ref. 5).
The 2001 NCEP report is an evidence-based report that extensively
references the scientific literature. The expert panel concluded that:
Trans fatty acids raise serum LDL-cholesterol levels. Through
this mechanism, higher intakes of trans fatty acids thus should
increase risk for CHD. Prospective studies support an association
between higher intakes of trans fatty acids and CHD incidence. (Ref.
89, p. V-15).
Based on these conclusions, the Expert Panel recommended for
individuals at increased risk for CHD that:
Intakes of trans fatty acids should be kept low. The use of
liquid vegetable oil, soft margarine, and trans fatty acid-free
margarine are encouraged instead of butter, stick margarine, and
shortening. (Ref. 89, p. V-15).
Lastly, a recent report of the IOM/NAS found ``a positive linear
trend between trans fatty acid intake and LDL cholesterol
concentration, and therefore increased risk of CHD'' (Ref. 140). The
report summarized that this would suggest a Tolerable Upper Intake
Level (UL) of zero, but because trans fats are unavoidable in ordinary
diets and achieving such a UL would require extraordinary changes in
dietary intake patterns that might introduce other undesirable effects
and unknown health risks, a UL was not proposed. Instead, the report
recommended ``that trans fat consumption be as low as possible while
consuming a nutritionally adequate diet.''
In summary, the recently updated Dietary Guidelines (Ref. 87 ),
NCEP (Ref. 89), and IOM/NAS (Ref. 140) reports, based on current
scientific evidence, consistently find that trans fatty acids are
associated with increased LDL-C levels and, therefore, that lower
intakes of both saturated and trans fatty acids are important dietary
factors in reducing the risk of CHD in the general population and for
those at increased risk for CHD. In addition, these new reports (Refs.
87, 89, and 140) either reversed previous scientific conclusions of no
deleterious effects of trans fatty acids (Refs. 2 and 4), or
strengthened previous scientific conclusions of an adverse effect of
trans fat intakes on CHD risk (Refs. 5 and 6). Thus, based on the
current body of scientific evidence, there is strong agreement among
the expert panels that the available evidence is sufficiently
compelling to conclude that trans fat intakes increase CHD risk.
Accordingly, these expert panels recommended, in addition to their
longstanding recommendations that Americans consume diets limited in
saturated fat, that consumers also select food products that are low in
trans fat. Although the expert panels' primary emphases remain on
limiting intakes of saturated fat (which contributes on average about
11-12 percent of calories in U.S. diets), they also have recommended
limiting intakes of trans fats (which contribute, on average, about 3
percent of calories in U.S. diets). These recommendations are made for
the general population (Refs. 87 and 140) and persons at increased risk
for CHD whose LDL-C is above goal levels (Ref. 89).
(Comment 1) Several comments on the November 1999 proposal
questioned whether the conclusions regarding trans fat would be
supported by pending scientific reviews. Some of these comments
recommended that FDA not issue a final rule until after publication of
Dietary Guidelines 2000. Other comments recommended waiting until the
IOM/NAS completes work on a review of dietary reference values for
macronutrients.
The Dietary Guidelines 2000 have been published (Refs. 87 and 88).
While they do not mention trans fat in its broad guideline, ``Choose a
diet that is low in saturated fat and cholesterol and moderate in total
fat,'' the recommendations from the Dietary Guidelines 2000 and the
accompanying advisory committee review clearly state that foods high in
trans fatty acids tend to raise blood LDL-C which increases the risk of
CHD. Reductions in intakes of both saturated and trans fats are
suggested for maintaining total fat to no more than 30 percent of
calories. Substitutions of foods low in trans and saturated fatty acids
(e.g., vegetable oils) for foods with higher levels of trans fatty
acids (e.g., hard margarines, partially hydrogenated shortenings) are
also recommended. Thus, in the Dietary Guidelines 2000, the
recommendations to reduce trans fat intake are definitive,
[[Page 41443]]
not tentative. Additionally, the recommendations in the Dietary
Guidelines 2000 are reinforced by similar findings and recommendations
from other recent expert panels (Refs. 89 through 91, and 140),
including those of the IOM/NAS report on macronutrients (Ref. 140),
which has also been published. The IOM/NAS report recommends that
``trans fat consumption be as low as possible while consuming a
nutritionally adequate diet.''
(Comment 2) One comment suggested that trans fat is a healthier
choice than saturated fat, quoting 1994 and 1998 statements that it
attributed to the American Heart Association (AHA) recommending that
margarine be used instead of butter and that trans fats displace
saturated fats in the diet. The comment suggested that, if AHA or
others in the scientific community recommend margarine be used instead
of butter, this establishes that hydrogenated vegetable oils and trans
fat have health benefits, at least in comparison to saturated fatty
acids. Several other comments stated that trans fats displace saturated
fats in the diet, thus implying that they are healthful alternatives to
saturated fats.
