Trans Fats in the American Diet

1
Trans Fats in the American Diet
Valentina Remig, PhD, RD, FADA Kansas State
University Manhattan, KS ADA Legislative and
Public Policy Committee (2006-2008)
2
No one fat type is perfect
3
History
19001950 Hydrogenation is developed and
perfected, creating the first fats of vegetable
origin
1990Mensink and Katan publish landmark study
diets rich in trans fats conferred the least
favorable effects on serum cholesterol levels vs
diets rich in saturated fats or oleic acid
2006FDA mandates that the Nutrition Facts panels
of all packaged food labels must indicate the
quantity of trans fats per serving
19501990 Partially hydrogenated fats are
increasingly used as the public begins to reject
animal and tropical fats
19902000A meta-analysis of studies finds that
a 2 increase in energy intake from trans fats
was associated with a 23 increase in the
incidence of coronary heart disease
Eckel et al. Circulation. 20071152231-2246.
4
Sources of trans fat

• Ruminants (meat and dairy)
• Bacteria in stomach create trans fat
• Hydrogenation/partial hydrogenation
• Trans fats formed during reduction of naturally
  occurring unsaturated fat
• Oil refining
• High temperatures during process create trace
  amounts of trans fat

5
Evidence for the ill effects of trans fats

• Trans fats have adverse effects on blood lipids
  and lipoproteins
• Epidemiological studies show a relationship
  between trans fat intake and coronary heart
  disease
• A 2 increase in energy from trans fat is
  associated with a 23 increase in CHD risk!

6
2 increase in energy from trans fats results in
23 increase in CHD risk
No. ofsubjects
No. ofevents
Type and year of study
Prospective cohort studies
78,778
1766
Nurses Health Study, 2005
1.33
Health Professionals Follow-up Study, 2005
38,461
1702
1.26
Alpha-Tocopherol Beta-Carotene Cancer Prevention
Study, 1997
21,930
1399
1.14
667
98
Zutphen Elderly Study, 2001
1.28
Pooled prospective studies
1.23
Retrospective casecontrol studies
1,388
671
EURAMIC, 1995
0.97
964
482
Costa Rica, 2003
2.94
78
44
Australia, 2004
2.50
Pooled prospective and retrospective studies
1.29
1.0
1.4
2.5
2.9
0.6
Multivariable relative risk of CHD with higher
trans fatty acid intake
Mozaffarian et al. New Engl J Med.
20063541601-1613.
7
2 increase in energy from trans fats results in
23 increase in CHD risk

• That just 4 extra grams of energy
• from trans fat per day!

8
1g of trans fat has 15 times the risk of CHD as
1g of saturated fat
Risk of CHD per 1 of fat per fatty acid class vs
carbohydrate
Assumes 35 energy from dietary fat.
Hu et al. New Engl J Med. 19973371491-1499.
9
Some alternatives to trans fats should be
approached with caution

• Industrial trans fats were originally introduced
  as an alternative to saturated fats
• We know the result
• Do we know that alternatives to trans fats
  are safe?

10
Interesterified fats are present in many products
today

• Little is known about health effects
• Recent report (2009) on acute metabolic changes
  with chemically and enzymatically interesterified
  stearic acid rich spread
• 85 increase in TAG with CIE vs NIE in
  obese subjects
• Increased stearic acid with CIE and EIE vs NIE

TAGtriacylglycerol CIEchemically
interesterified EIEenzymatically
interesterified NIEnon-interesterified.
Robinson et al. Lipids. 20094417-26.
11
Professional societies have taken stances on
trans fat consumption

• Foods containing industrially derived TFA should
  be minimized....TFA replacement strategies
  should not result in a higher TFA and SFA

• A recent meta-analysisfound that a 2 increase
  in energy intake from trans fatty acids was
  associated with a 23 increase in the incidence
  of coronary heart disease
• Recommends limiting trans fat consumption to lt1
  total energy/day

• There is a positive linear trend between trans
  fatty acid intake and total and LDL cholesterol
  concentration, and therefore increased risk of
  CHD, thus suggesting a Tolerable Upper Intake
  Level (UL) of zero

12
Grams trans fats in a high trans fat menu
around the world
A large serving of nuggets and French fries
100 g biscuits/ cakes/wafers
100 g microwave popcorn
0
10
20
30
40
50
Gram
Numbers in brackets are trans fats in each menu
item.
Stender et al. Food Nutr Res. 200852. doi
10.3402/fnr.v52i0.1651.
13
Denmark regulated artificial trans fatsas of 2003

• Trans fats may not comprise gt2g/100g of oil/fat
• Trans fat free is defined as lt1g/100g of
  oil/fat in final product
• It is forbidden to sell products exceeding
  2g/100g oil/fat
• Punishable by up to 2 years in prison
• Trans fats eliminated from margarines/spreads
  without increasing SFAs

Leth et al. Atheroscler Supps. 2006753-56.
14
Current and proposed legislation restricting use
or labeling of trans fats
National Conference of State Legislatures.
Available at http//www.ncsl.org/programs/health/
transfatmenulabelingbills.htm. Accessed January
9, 2009.
15
FDA rounding rule allows for significant trans
fats

• Total trans fats of lt0.5g/serving can be listed
  on Nutrition Facts panel as 0g trans fat
• Allows for up to 0.49g trans fat per serving
• Serving size definition is often quite small
• Results in consumption of 2?3 or more servings at
  a time
• Individual can consume up to 1.4g trans fat and
  believe they have consumed 0g

16
Example 1 Kelloggs Rice Krispies Treats Cereal

• Actual trans fat 0.444g/serving
• Serving size ¾ cup

U.S. Department of Agriculture, Agricultural
Research Service. 2008. USDA National Nutrient
Database for Standard Reference, Release 21.
Nutrient Data Laboratory Home Page. Available at
http//www.ars.usda.gov/ba/bhnrc/ndl.
17
Example 2 Pillsbury Buttermilk Biscuit
Refrigerated Dough

• Actual trans fat 0.350g/serving
• Serving size 3 biscuits (64 g)

U.S. Department of Agriculture, Agricultural
Research Service. 2008. USDA National Nutrient
Database for Standard Reference, Release 21.
Nutrient Data Laboratory Home Page. Available at
http//www.ars.usda.gov/ba/bhnrc/ndl.
18
Example 3 Crème-Filled Sponge Cake (eg,
Twinkies, Little Debbie)
Actual trans fat 0.459g/serving
U.S. Department of Agriculture, Agricultural
Research Service. 2008. USDA National Nutrient
Database for Standard Reference, Release 21.
Nutrient Data Laboratory Home Page. Available at
http//www.ars.usda.gov/ba/bhnrc/ndl.
19
Underestimation of portion size may lead to
accumulation of trans fat
Differences between standardized and actual
portion sizes
Burger K et al. J Am Diet Assoc.
2007107-611-618. U.S. Department of Agriculture,
Agricultural Research Service. 2008. USDA
National Nutrient Database for Standard
Reference, Release 21. Nutrient Data Laboratory
Home Page. Available at http//www.ars.usda.gov/b
a/bhnrc/ndl.
20
Trans fat content in leading Buttery Spreads with
0g labels
Significantly less trans fat with Smart Balance
than with other brands
21
NIP Educational tool to help clients assess
Nutrition Facts panel

• Nutrition Facts
• Examine Nutrition Facts panel to determine amount
  of trans fat per serving
• Treat 0g with skepticismassume up to 0.5g
• Ingredient list
• If trans fat is listed as 0g, look for
  hydrogenated or partially hydrogenated oils
  in ingredient list
• Foods with these oils contain some trans fats
• Portion size
• Look for the portion size on the Nutrition Facts
  panel and be honest about how much you eat
• Be aware that if you eat more than the nominal
  portion size, you may be accumulating significant
  trans fat, even if it says 0g trans fat

22
Conclusions

• Trans fats have negative impact on cardiovascular
  markers and CHD
• 15 times more harmful than sat fats
• Reducing trans fats could significantly impact
  CHD
• Demonstrated in Danish experience
• Professional societies and FDA recommend limiting
  trans fats in diet to lt1 total energy
• But zero isnt necessarily zero on trans fat
  labels
• Underestimation of portion size may lead to
  accumulation of significant trans fats, even in
  foods labeled 0g trans fat
• Smart Balance buttery spread is made from natural
  fats and oils with no hydrogenation
• Lowest actual trans fats among leading spreads
  with 0g trans fat/portion labels