หลักฐานทางวิทยาศาสตร์ระบุว่า การบริโภคไขมันอิ่มตัว (saturated fat) ไขมันชนิดแทรนส์ (trans fatty acid) มีผลเสียต่อสุขภาพ เช่นเดียวกับกรดไขมันชนิดอิ่มตัว (saturated fatty acid) เป็นสาเหตุของการเพิ่มระดับ Low-Density Lipoproteins (LDLs) ซึ่งเป็นโทษต่อสุขภาพ เพิ่มความเสี่ยงของโรคหลอดเลือดหัวใจตีบ (Coronary Heart Disease) และลด High-Density Lipoprotein (HDLs) ไม่ก่อโทษต่อสุขภาพ (HDL-C)

USFDA ได้กำหนดให้ระบุไขมันชนิดแทรนส์ (trans fat) ตั้งแต่วันที่ 1 มกราคม พ.ศ. 2549 ในฉลกาโภชนาการ (nutrition label)
เพื่อให้ข้อมูลแก่ผู้บริโภค โดยระบุในบรรทัดต่อจากไขมันชนิดอิ่มตัว โดยไม่ต้องระบุ % Dialy Value

Trans Fat Labeling

L42. Why is FDA requiring that trans fatty acids be listed in nutrition labeling?

Answer: FDA is requiring that trans fatty acids be listed in nutrition labeling in response to a petition from the Center
for Science in the Public Interest and to published human studies that show that intake of trans fatty acids, similar to
the intake of saturated fatty acids, increases low-density lipoprotein-cholesterol (LDL-C) ("bad cholesterol") in the blood.
An elevated LDL-C increases the risk of developing coronary heart disease. Reports published by the Institute of
Medicine of the National Academy of Sciences (IOM/NAS) and the Federal government have recommended that
Americans limit their intake of trans fat and other cholesterol-raising fats while consuming a nutritionally adequate diet.
For Americans to follow these recommendations, they must know the amount of trans fatty acids in the individual foods
that they eat. Therefore, FDA is requiring that this information be provided in nutrition labeling to assist consumers in maintaining healthy dietary practices. (68 FR 41434, July 11, 2003)

L43. How is trans fat defined for labeling purposes?

Answer: The Agency's regulatory chemical definition of trans fatty acids is "all unsaturated fatty acids that contain
one or more isolated double bonds in a trans configuration." Trans vaccenic acid, a trans fatty acid with a single
double bond, and other trans fatty acids of ruminant origin with either a single double bond or nonconjugated double
bonds are included in this definition. Trans fatty acids with conjugated bonds are not included because they do not
meet the Agency's definition. Thus, trans fatty acids, regardless of origin, that meet the above definition are to be
included in the label declaration of trans fat. Further, using FDA's regulatory chemical definition, the categories
"trans fatty acids" and "conjugated fatty acids" are mutually exclusive. The definition of trans fatty acids, excluding
fatty acids with conjugated double bonds, is consistent with the way that cis isomers of polyunsaturated fatty acids
are defined. (68 FR 41434 at 41461, July 11, 2003.)

L44. Do trans fatty acids need to be listed when monounsaturated fatty acid and polyunsaturated fatty acids
are not listed?

Answer: Yes. The listing of trans fatty acids is mandatory even when monounsaturated fatty acid and
polyunsaturated fatty acids are not listed. 21 CFR 101.9 (c) , (c) (2) (ii) , (c) (2) (iii) , and (c) (2) (iv) .

L45. How should trans fatty acids be listed?

Answer: Trans fatty acids should be listed as "Trans fat" or "Trans" on a separate line under the listing of saturated
fat in the Nutrition Facts label (see figure) . The word "trans" may be italicized to indicate its Latin origin. Trans fat
content must be expressed as grams per serving to the nearest 0.5-gram increment below 5 grams and to the
nearest gram above 5 grams. If a serving contains less than 0.5 gram, the content, when declared, must be
expressed as "0 g." (21 CFR 101.9 (c) (2) (ii) ) .

46. If a serving contains less than 0.5 gram of trans fat, when would "0 g" of trans fat not have to be declared?

Answer: For conventional food products (those food products other than dietary supplements) , declaration
of "0 g" of trans fat is not required for such products that contain less than 0.5 g of total fat in a serving and no
claims are made about fat, fatty acid or cholesterol content. If trans fat is not listed, the statement "Not a significant
source of trans fat" may be placed at the bottom of the table of nutrient values in lieu of declaring "0 g" of trans fat.
If these claims are present, then the statement "Not a significant source of trans fat" is not an option and the
declaration of "0 g" of trans fat is required. 21 CFR 101.9 (c) (2) (ii)

The labeling of dietary supplements is different than the labeling of conventional foods. Certain nutrients in
conventional foods, when not present or when present at levels that the agency has determined to be "zero"
(see 21 CFR 101.9 (c) ) , must be listed as zero on conventional food labels. However, when those same nutrients
are not present in dietary supplements or present in dietary supplements at levels that the agency has determined,
for conventional foods, to be "zero," such nutrients must not be listed on dietary supplement labels. Amounts of "0 g"
and "Not a significant source..." statements are not allowed in the nutrition labeling of dietary supplements (i.e.,
Supplement Facts) . Consequently, when the amount of trans fat in a dietary supplement is less than 0.5 gram
per serving, trans fat must not be listed on the Supplement Facts label. 21 CFR 101.36 (b) (2) (i)

L47. Why is there no % DV for trans fat?

Answer: Although the updated Nutrition Facts label will now list the amount of trans fat in a product, be aware
that it does not have a % DV for trans fat. While scientific reports have confirmed the relationship between trans
fat and an increased risk of CHD, none has recommended an amount of trans fat that FDA could use to establish
a DV. Without a DV, a % DV cannot be calculated. As a result, trans fat will be listed with only a gram amount.