Cardio­metabolic Health

Cardiometabolic health is a relatively new term that encompasses cardiovascular and metabolic diseases, including type 2 diabetes and metabolic syndrome. Collectively, such conditions are the leading cause of preventable death worldwide. They all share similar risk factors (e.g., overweight/obesity, elevated blood pressure) which can be modified by diet and lifestyle choices. The available evidence indicates that eggs, when consumed as part of an overall healthy diet pattern, do not affect risk factors for cardiometabolic disease. Recent recommendations from the American Heart Association, American College of Cardiology and American Diabetes Association do not limit egg or cholesterol intake, a change from earlier guidance from these organizations. In fact, several global health organizations, including Health Canada, the Canadian Heart and Stroke Foundation, the Australian Heart Foundation and the Irish Heart Foundation, promote eggs as part of a heart-healthy diet.

Given the public health significance of understanding cardiometabolic diseases, research on risk reduction remains an active area of pursuit. For example:

  • A randomized controlled study in people with metabolic syndrome showed that those consuming three whole eggs per day as part of a reduced carbohydrate diet experienced favorable changes in HDL-cholesterol, insulin sensitivity, and other aspects of the lipoprotein lipid profile
  • A randomized controlled weight loss trial in people with diagnosed type 2 diabetes showed improved lipid and glucose markers following consumption of 2 eggs per day for 12 weeks.
  • An egg-based breakfast, rich in protein (35% energy; 26.1 g egg protein), promoted glycemic control in people with type 2 diabetes and pre-diabetes relative to a high-carbohydrate breakfast.

Health Experts Share Insights on Recent Egg Research

As discussed in a previous post, the recent study on egg consumption published in Atherosclerosis was surprising and contradicts more than 40 years of research demonstrating that healthy adults can enjoy eggs without significantly impacting their risk of heart disease. As we continued watching news on the topic unfold, we saw that many health professionals had independently reviewed the study and voiced their interpretations of the study’s results on news, health and social media websites.

If you are interested in a detailed analysis of the study and what it means to you as a health professional, check out some of these insights from notable health and nutrition experts:

  • Sports dietitian Chris Mohr PhD, RD, explains on MohrResults.com, “With this study there were a ton of controllable factors, which all can play a role in atherosclerosis, that weren’t examined.”
  • Further insights are provided by Sheah Rarback, MS, RD, in the Miami Herald. “Saturated and trans fatty acids are the primary culprits in raising blood cholesterol levels. Recent clinical studies on the effect of dietary cholesterol on plasma lipid levels have shown that it has a measurable — but mostly clinically insignificant — effect on plasma cholesterol levels.”
  • Dr. Briffa continues on DrBriffa.com, “Another fundamental problem with research of this nature as it relies on individuals reporting how much and/or often they eat of specific foods.”
  • Susan Dopart, MS, RD, CDE agrees with this position on SusanDopart.com. “Research shows that when you have patients ‘recall’ what they ate, especially over many years like this study did, the accuracy is quite questionable.”
  • Taking a closer look at the data on Health Goes Strong, Robyn Flipse, MS, RD, points out, “What the research did show is that eating eggs improves the overall blood cholesterol profile, but that was nowhere to be found in the headline.”
  • When asked about the study by ABC News, Dr. Steve Nissen of the Cleveland Clinic cautioned, “It is extremely important to understand the differences between ‘association’ and ‘causation’.”
  • Putting things into perspective, Elizabeth Ward, MS, RD blogged on WebMD, “This is a single, observational study that does not prove cause and effect and does not change the fact that more than 40 years of research suggests that healthy people can eat eggs without having a significant impact on their risk for heart disease.”
  • Martha McKittrick, RD, CDN, CDE offers a good piece of advice for consumers on City Girl Bites, “The majority of studies have shown that eggs can fit into a healthy diet. The key is moderation. The effect of the cholesterol found in eggs on blood cholesterol will vary from individual to individual.”
  • Concluding her article in the Clarion Ledger, Kathy Warwick, RD, CDE states, “Eggs are a nutritious low-calorie, high protein food that provide 13 essential vitamins and minerals. As with all things dietary, eggs can be part of healthy balanced diet. Daily exercise and maintaining a healthy weight are crucial for preventing heart disease.”

Obviously, many health experts agree there are several limitations to the study and the results should be interpreted in light of the entire body of research on eggs, cholesterol and heart disease. We would like to thank the many health professionals who have shared their insights and continue to inform consumers about the nutritional benefits of eggs!

Egg Research Update: Atherosclerosis Study

A study published in the journal Atherosclerosis last week suggested that eating eggs can be almost as damaging to you heart as smoking cigarettes. Maybe you’ve seen the press coverage? It was all over the media last week and, needless to say, it kept us pretty busy at the Egg Nutrition Center. First thing we did was contact seven cardiovascular researchers for their perspectives on the study; three of the seven are among the leading epidemiology researchers in the country. All pointed out a number of flaws in the study design, ranging from:

  • “this was a cross sectional study and, as such, it is impossible to reach a case-and-effect conclusion”
  • “there didn’t appear to be any dietary control for other dietary constituents (besides eggs)—a fatal flaw”
  • “the failure (of the researchers) to adjust…for age is a major if not fatal flaw”
  • “the subjects were already sick…this is the classic setup for reporting bias that could lead to exactly the results that they found in that those who were sickest reported the highest egg intakes…”.

And on and on. Most of the researchers we queried wondered how the study was accepted for publication considering its flaws.
It should be noted that the lead researcher on this project has had issues with eggs before. A couple of years ago he was quoted as saying that an egg was worse for you than a Kentucky Fried Chicken Double Down sandwich (a breadless sandwich with three pieces of fried chicken; 540 kcals; almost 40 gms fat; 1400 mg sodium). A dubious statement, to say the least, but one that may help explain a pre-conception the author has about eggs that may have carried over into the recent study.

It is always a shame when studies of this nature garner so much media attention. While it would have been nice for reporters to have done their homework first and uncovered some of the flaws and biases associated with this study before running with it, I suppose that the headline (Eggs are as Bad as Cigarettes) was just too tantalizing to pass up.

At the Egg Nutrition Center we’ll continue to study the effects of eggs on human health as we’ve always done, and we’ll let the chips fall where they may regarding the results of the projects we fund. We adhere to the Guidelines for Industry Funded Research and request that all investigators who work with us do the same. We realize that not every study will yield a positive result; that’s the nature of science. The key is to support well- designed, well-controlled studies so that you can feel good about the results, whatever they happen to be. In the case of the recent Atherosclerosis paper, I’m not so sure that’s what we got.

American Academy of Nurse Practitioners (AANP) Conference

Last week ENC was in Florida for the AANP conference!  Besides the rain and storms, it was a great conference. The group was very happy we were spreading our education messages and information. One of our Health Professional Advisory Panel members, Dixie Harms DNP, ARNP, FNP-C, BC-ADM, FAANP, presented “The Truth Behind  Dietary Cholesterol and Lipids” during a product showcase.

ENC sponsored the grand opening breakfast reception and provided some of our health professional and client materials. We were able to educate over 450 Nurse Practitioners and students over the course of three days!

It was a noticeable change that NPs were aware of the cholesterol research and eager to know what was new in eggs. This was a refreshing change from other shows. MyPlate materials were very popular as NPs felt they were perfect for client education.

We had a great time meeting new people and listening to feedback from nurse practitioners! If you attended the AANP national conference, let us know your thoughts!

What You Told Us – Your Thoughts about Cholesterol

We recently conducted a survey with our health professional groups (n = 2440) to determine perceptions of eggs and nutrition. The survey has proved to be a great way to connect with health professionals and to learn what education and materials ENC should present at conferences and events.

The good news is 97.41% of the respondents correctly identified eggs as a healthy part of a diet, and 45% tell their healthy clients to have an egg a day or not to limit egg intake. Over 35%, however, still recommend consuming only 3-4 eggs/week, and 70% of respondents told those with cardiovascular risks over 70% to consume less than 3-4 eggs per week.   The truth is, an egg a day is OK!

We know generally that dietary cholesterol does not impact serum cholesterol (except with hyper-responders).  Interestingly when health professionals were asked about contributors to heart disease cholesterol in the diet ranked low, but when asked the reasons for the suggestion to limit eggs – cholesterol was cited at nearly 50%.

Here are some key research recaps (although there are many more):

  • More than 40 years of research have demonstrated that healthy adults can enjoy eggs without significantly impacting their risk of heart disease.
    [
    Harman NL, et al. Increased dietary cholesterol does not increase plasma low density lipoprotein when accompanied by an energy-restricted diet and weight loss. European Journal of Nutrition 2008; 47:287-293.]
  • The 2010 Dietary Guidelines for Americans support the role of eggs in a healthy diet. The report, released in January 2011, states that healthy individuals can enjoy an egg daily and suggests an egg a day does not result in increased blood cholesterol levels.
    [U.S. Department of Agriculture and U.S. Department of Health and Human Services. Dietary Guidelines for Americans, 2010. 7th Edition, Washington, DC: U.S. Government Printing Office, December 2010.]
  • Egg consumption does not significantly impact the LDL:HDL ratio – one of the best known and scientifically established indicators of heart disease risk. A 2008 review of more than 30 studies published in the Journal of the American College of Nutrition argued that the LDL:HDL ratio is a much better indicator of heart disease risk than either indicator alone.
    [Fernandez ML and Webb D. The LDL to HDL Cholesterol Ratio as a Valuable Tool to Evaluate Coronary Heart Disease Risk. JACN 2008;27 (1): 1-5.]

Here is some great information that you can use with other health care providers and your patients.

There is still much confusion about cholesterol and eggs, even though there is over 40 years of research that tells a positive story. In future posts, we’ll look beyond the cholesterol story and highlight the other nutritious and delicious parts of the egg.

Advances in Protein Research

Is it just me or is there growing interest in understanding the importance of the long overlooked macronutrient protein? Protein has always seemed like the Cinderella of diet planning. Carbohydrates and fats always commanded much more attention in dietary guidance, including protein as only afterthought.

As the baby boomer generation enters their senior years there seems to be a growing concern about keeping healthy through diet and exercise. Baby boomers are seeing that the high carbohydrate/low fat meals they were advised to prepare left them perpetually hungry and often at risk of cardiovascular disease related to the unattractive spare tire around their abdomen.  It’s time to ask why have the last 20 years seen an epic growth of obesity, metabolic syndrome and little change in the cardiovascular disease rates despite this supposedly healthy dietary advice?

Enter the shocking success of the Atkins/South Beach diets that found followers experienced more sustained relief from hunger and improved cardiovascular risk factors resulting from a reduction in carbohydrates and an increase in both fat and protein intake. People who previously sacrificed their favorite full fat meat, cheese and chicken dishes found that they could eat these foods again if they gave up white rice, bagels and pasta and surprisingly, were rewarded with increased high density lipoprotein levels along with reduced triglycerides and body weight garnering praise from their physician.

Now the scientific community appears to be catching up with the success of the higher protein intake. Two published studies1,2 looked at the effect of high protein intake on diabetes control.  In the Why WAIT (Weight Achievement and Intensive Treatment) Program, developed at the Joslin Diabetes Center for diabetes weight management in clinical practice, a high protein-low carbohydrate (30% protein [1.5–2 g/kg] and 40% carbohydrates) energy–restricted diet was tried within a multidisciplinary diabetes weight management program for 12 weeks. The authors conclude that an intake of 1.0-1.5 gm/kg of protein is appropriate for diabetics, helping to improve many health risk factors including a lower HbA1c in addition to a reducing total serum cholesterol, LDL cholesterol, triglycerides, blood pressure and markers of inflammation. The researchers reported diabetic patients were less hungry after meals, which contributes to their lower calorie intake and subsequent reduced body weight while maintaining muscle mass. The authors do however make the point that a higher protein intake may be contra- indicated in patients with diabetes accompanied by chronic kidney disease.

More recently, a study published in Advances in Nutrition 3 suggests the brain’s control of appetite is greatly affected by protein intake. From both animal and human research the authors conclude that after protein consumption, peptide hormones are released from the gastrointestinal tract that communicates information about the peripheral energy status to the brain. These hormones control food intake by acting on brain regions involved in energy homeostasis such as the brainstem and the hypothalamus.  High-protein diets lead to greater activation than a normal-protein diet in the regions of the brain responsible for satiety. These areas are triggered particularly by leucine, a branched chain amino acid that influences the reward and motivation aspects of eating behavior and plays an important role in the reduced hedonic response associated with a high-protein intake.

1         Hamdy, O. Issues in Nutritional Treatment of Type 2 Diabetes Mellitus and Obesity, Current Diabetes Reports, April 2011, 11(2):75-6.

2         Hamdy, O. and Norton E.S. Protein Content in Diabetes Nutrition Plan, Current Diabetes Reports, April 2011, 11(2):111-9.

3         Journel, M. et. al. Brain Responses to High Protein Diets, Advances in Nutrition, 2012, 3:322-9.