Banning Trans Fats: Clinical Implications

Susan Yox, RN, EdD; Jennifer Seymour, PhD


November 15, 2013

Editorial Collaboration

Medscape &

Editor's Note:
The US Food and Drug Administration's (FDA) recent announcement that it has taken the first step to potentially remove trans fats from processed foods has garnered a lot of attention from both the medical/scientific community and consumers. Many health professionals believe that this step is long overdue. Medscape interviewed Jennifer Seymour, PhD, a Senior Scientist at the Centers for Disease Control and Prevention's Division of Nutrition, Physical Activity, and Obesity, to learn a bit more about trans fats.

Medscape: Experts believe that banning trans fats will save lives. Our first question is, how were the estimates developed that banning trans fatty acids (TFAs) would prevent 10,000-20,000 myocardial infarction-related deaths and 3000-7000 coronary heart disease-related deaths each year in the United States?

Jennifer Seymour, PhD, Centers for Disease Control and Prevention

Jennifer Seymour, PhD: These CDC health impact estimates were published in JAMA in 2012.[1] They were based on FDA estimates of average consumption of TFAs in the United States and on previous FDA estimates of health impact.

In 2012, FDA estimated that TFA intake in the United States had decreased from about 4.6 grams per person per day in the late 1990s to about 1.3 grams per person per day by 2010. The 1.3 grams per person per day corresponds to an intake of about 0.6% of energy.

In 2003, FDA estimated that 600-1200 coronary events and 240-480 deaths from coronary heart disease (CHD) could be prevented each year if TFA intake were reduced by 0.04% of energy. Extrapolating from this FDA estimate of health impact, assuming a linear association with health effects (and no effects of other interventions), and adjusting to the current US statistics on coronary events (myocardial infarction or fatal CHD), CDC estimated that eliminating industrially produced TFAs from the current levels of 0.6% of energy may prevent as many as 10,000-20,000 coronary events and 3000-7000 CHD deaths annually.

The 2003 FDA estimate considered only the effects of TFA on low-density lipoprotein (LDL) cholesterol levels (lower-bound estimates), either alone or in conjunction with the effects on high-density lipoprotein (HDL) cholesterol levels (upper-bound estimates). Because TFAs may influence CHD risk through mechanisms other than their effect on levels of LDL and HDL cholesterol, the benefits of eliminating industrially produced TFAs in the US diet may possibly be even greater.

Medscape: Can you tell us about any new research or other compelling evidence on the deleterious effects of TFAs? Is there any research on the effects of TFAs beyond CHD that clinicians should know about?

Dr. Seymour: Scientific evidence shows that consumption of TFAs raises LDL serum cholesterol, lowers HDL cholesterol, and consequently, increases the risk for CHD. Research has also linked TFA intake to proinflammatory effects, endothelial dysfunction, and reduced insulin sensitivity in persons with insulin resistance.[1] The Institute of Medicine and the Dietary Guidelines for Americans have stated that TFA consumption should be kept as low as possible while maintaining a nutritionally adequate diet.

Medscape: Now that public awareness is probably increased, is this an opportunity for clinicians to advise patients and to reinforce the message about harms of trans fats? In CDC's view, what are the key points that clinicians should include when advising patients, if and until TFAs are totally banned?

Dr. Seymour: CDC has created a fact sheet about TFAs that provides information for clinicians. Clinicians may advise their patients to:

  • Read the Nutrition Facts label and ingredient list to compare foods.

    • Choose products with 0 grams of trans fat;

    • Check the ingredient list to see whether there is any partially hydrogenated oil in the product (and avoid those products);

    • Because products containing less than 0.5 grams of trans fat per serving can be labeled as having 0 grams trans fats, checking the ingredient list is important to avoid all artificial trans fat.

  • When choosing foods low in trans fat, make sure that they are also low in saturated fat and cholesterol: Look for foods with 5% of the daily value or less. Foods with 20% or more of the daily value of these 2 components are high in fat.

  • Use monounsaturated fat (canola and olive oil) and polyunsaturated fat (soybean, corn, and sunflower oil) in recipes that call for fat.

  • A good way to avoid trans fat is to eat a balanced diet rich in fruits, vegetables, whole grains, lean sources of protein, and low-fat or fat-free dairy products.

  • Ask your grocer to stock products free of "partially hydrogenated oil" and "shortening."

  • Talk with your favorite restaurant establishment about current use of partially hydrogenated oils or changing to a menu that is 100% free of "partially hydrogenated oil" and "shortening."

  • Choose restaurants that do not use partially hydrogenated oil to prepare food.

Related Resources

CDC: Nutrition for Everyone: Trans Fat

FDA: Talking About Trans Fat: What You Need to Know

Jennifer Seymour, PhD, is currently Senior Scientist for Policy Initiatives in the Division of Nutrition, Physical Activity, and Obesity at CDC. In this position she addresses the scientific and policy implications of nutrition initiatives. Dr. Seymour was CDC's lead scientific reviewer for HBO's Weight of the Nation documentary series and public-awareness campaign, and she has worked with USDA for several years on efforts to change the SNAP-Ed program to include public health obesity prevention efforts. In 2010, Dr. Seymour worked as a Policy Advisor in the Office of First Lady Michelle Obama at the White House. She assisted in planning and carrying out activities for the Let's Move! Initiative. At CDC, she continues to work with Let's Move! and to focus on policy, systems, and environmental interventions to promote nutrition.

Dr. Seymour received her PhD in Nutrition and Health Sciences from the Division of Biological and Biomedical Sciences at Emory University in 2000 and completed her dissertation while working at the National Home Office of the American Cancer Society in Epidemiology and Surveillance Research. She has a BA in Anthropology from Rutgers University.