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.

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Unscrambling the Latest Egg Controversy

Today’s post comes from Katherine Brooking, MS, RD.* Brooking is a nutrition communications consultant, appearing regularly in national and local media to discuss nutrition topics. She is also co-author of the popular website and blog, Appetite for Health.kbrooking-150x150

As an RD, I was surprised to see the headlines in August claiming that eating egg yolks may be as bad for your health as smoking cigarettes.  This claim runs directly counter to decades of sound research demonstrating that healthy adults can enjoy an egg a day without increasing their risk for heart disease. I decided to dig a bit deeper to understand the latest controversy.

The news reports comparing egg consumption with cigarette smoking emerged as a result of a study published in the August 13 issue of the journal Atherosclerosis. (Spence et. al)  In this study, researchers examined data on 1,231 men and women, average age of about 62, who were patients at vascular prevention clinic at London Health Sciences Centre in Canada.

The authors asked study participants about lifestyle practices — including such things as smoking and egg ingestion. People with more plaque in their arteries reported eating more eggs, and researchers concluded that so-called “egg-yolk-years” (that is, the number of eggs eaten per week times the number of years in the study) were a significant predictor of heart disease and that “regular consumption of egg yolk should be avoided by persons at risk of cardiovascular disease.”

There are multiple problems with this recent study, the most obvious of which may remind you of one of the first things you heard in stats class: correlation does not mean causation. Although study participants were asked about egg consumption, the authors failed to control for other aspects of diet. Foods other than eggs (including foods high in saturated fat, a known contributor to heart disease) may have lead to the increases in arterial plaque.

In addition, the study relied on patient dietary recall and patient self-reporting on a yearly basis. As most RDs can attest, dietary recall can be highly inaccurate.  Few patients can remember what they ate last week, never mind how many eggs consumed in a year.

At the same time, we have a wealth of data that contradicts the findings of the Spence study. Years of epidemiological evidence indicate that dietary cholesterol does not increase the risk of heart disease in healthy individuals. Clinical studies have shown that two thirds or more of the population do not have a considerable increase in blood cholesterol after a dietary cholesterol challenge for extended periods of time, whereas in those who do respond, both LDL-C and HDLC increase, and therefore they maintain their LDL-C/HDL-C ratio. (Kanter et al.)

Further, in urging some segments of the population to avoid eggs, the Spence study ignores the nutritional contribution of eggs to a healthy, balanced diet.  Eggs are a naturally nutrient-dense food, containing varying amounts of 13 essential nutrients in a package with a relatively low number of calories: just 70 for a large 50 gram egg. Eggs are one of the few natural sources of vitamin D and provide an excellent source of choline and selenium and a good source of vitamin B12, phosphorus and riboflavin.

The nutrients in eggs can play a role in weight management, muscle strength, healthy pregnancy, brain function, eye health and more. The high-quality protein in eggs has been shown to contribute to satiety and can help individuals maintain a healthy weight.

Similar thoughts were also expressed in an earlier post by Mitch Kanter, Ph.D and executive director of the Egg Nutrition Center.

The media is often quick to demonize specific food or food groups and slow to find flaws with individual studies.  In the case of eggs, the evidence-to-date falls heavily in favor of consuming eggs on a regular basis, as part of a healthy and balanced diet.

*Disclaimer: This post is sponsored by the Egg Nutrition Center. However the views and opinions expressed in this post are my own.

Happy National Cholesterol Education Month!

As mentioned in Mary Donkersloot’s post earlier this month, September is National Cholesterol Education Month. Here at ENC, we think this is the perfect time for health professionals to clarify misconceptions surrounding dietary cholesterol and also educate consumers about optimizing lipid profiles through healthy lifestyle choices.

Given the confusion among consumers surrounding cholesterol and egg yolk from the recent Atherosclerosis study, we wanted to highlight an invited commentary from Antonis Zampelas, nutrition professor at the Agricultural University of Athens in Greece, which will also be published in an upcoming issue of the journal. Zampelas explains the greater body of research supports the notion that egg consumption is unlikely to have clinically significant effects on cardiovascular disease risk among healthy individuals, and may in fact be anti-atherogenic by increasing LDL-particle size. Eggs also contain the antioxidants lutein and zeaxanthin, which may decrease LDL oxidation. Ultimately, Zampelas concludes that the study results should be viewed with caution since important confounders, such as saturated fat, were not controlled.

As health professionals, we are uniquely positioned to clarify these misconceptions and provide our clients with evidence-based recommendations regarding cholesterol and heart health. This is a fitting month to make that your goal.

Over 65 million Americans have high cholesterol, and many may not even know it. Join the cause to raise consumer awareness and education about high cholesterol and the dietary and lifestyle choices associated with a healthy lipid profile. Be sure to check out the many helpful resources provided by the National Heart Lung and Blood Institute for health professionals to participate in the National Cholesterol Education Month campaign, including individual and group teaching tools, heart healthy recipes, fact sheets, bulletin boards and more.

How are you participating in the campaign this month?

New Egg Nutrition Center Sponsored Article Explores Dietary Cholesterol Issue

The Egg Nutrition Center recently published an article in the journal Advances in Nutrition entitled, Exploring the Factors that Affect Blood Cholesterol and Heart Disease Risk: Is Dietary Cholesterol as Bad for you as History Leads us to Believe?  The article is a review of a symposium that ENC sponsored at the Experimental Biology meetings last year. Symposium participants included Dr. Penny Kris-Etherton from Penn State University; Dr. David Katz from Yale University; Dr. Maria Luz-Fernandez from the University of Connecticut, and Dr. Kasey Vickers from the National Heart, Lung and Blood Institute (NHLBI).

Among other things, the article addresses much of the newer clinical and epidemiological research which indicates that dietary cholesterol is not the “boogeyman” it once was thought to be. Some of the symposium presenters pointed out the difficulty in trying to tease out other dietary factors from dietary cholesterol when analyzing study results suggesting, in essence, that the presence of food components such as saturated fat, sodium, simple sugars, and calories may well be the culprits in elevated disease risk and that dietary cholesterol may have been unfairly indicted by “the company it keeps.”

The article also briefly delves into the paleoanthropological argument that our prehistoric ancestors subsisted on a diet that was rich in cholesterol sources such as eggs, bone marrow, and organ meat, and so it makes sense that we would have evolved and adapted to thrive on cholesterol-containing diets.

A discussion of the current global view of dietary cholesterol is also addressed in the paper. One of the symposium presenters points out the fact that many countries in the European Union, as well as Korea, India, Canada, New Zealand and others no longer have a daily dietary recommendation for cholesterol, indicating their belief that other dietary factors are more culpable in the development of heart disease.

Finally, the paper addresses the implications of removing otherwise healthy foods from the diet in an effort to lower dietary cholesterol intake. It points out that eggs, for example, are a key source of high quality protein, carotenoids, essential fatty acids, various vitamins and minerals and are one of the few dietary sources of choline, a key nutrient in fetal brain development. Removal of a nutrient-rich food such as eggs from the diet can make it harder to attain optimal intakes of any or all of these nutrients.

Overall, the paper represents a somewhat new and growing development in the nutrition science literature—a re-assessment of long standing beliefs about the foods we eat and the diets we prefer. With the troublesome and growing obesity epidemic in the US and abroad, as well as alarming rates of Type II diabetes and other related conditions, this re-assessment is long overdue. We think this paper can add to the debate.

If you’re interested in receiving a copy of the paper please contact us at info@eggnutrition.org. We’ll be happy to send the article to you.

Eggs: A Nutrition Counselor’s Perspective

In honor of National Cholesterol Education Month, today’s blog post comes from Mary Donkersloot, a registered dietitian and nutrition consultant with a private nutrition practice in Beverly Hills, California. Donkersloot has helped individuals dealing with diabetes, heart disease, weight management, and eating disorders for more than 20 years. She is also one of ENC’s Health Professional Advisors.

When I was a child, eggs were considered a perfect food, and my mother felt she was doing a good thing by making them for us before she rushed us off to school.  The discovery of cholesterol and its link with heart disease has put that reputation into question.  With 180 milligrams of cholesterol in each egg yolk – nearly at the daily dietary recommendation of 300 milligrams for healthy Americans – we began to eat eggs sparingly, often feeling guilty when eating them.

But are the dangers of eggs all they are cracked up to be?  New research may indicate that they are not.  Studies have shown that adding an extra 200 milligrams of cholesterol a day to the diet increases blood cholesterol levels only slightly, with a minimal effect on heart disease risk.  I tell my clients that the benefits of eggs may outweigh that risk, since eggs are low in saturated fat and contain many other nutrients that are good for you – protein, folic acid, choline, lutein (good for eye health) and vitamin D.  So eggs effect on risk for heart disease can’t be understood only based on their cholesterol content.

Perhaps even more important, people respond in different ways to the cholesterol in their food.  Scientists sort people into two categories when it comes to cholesterol. The “responders” are those whose blood cholesterol goes up when they eat foods high in cholesterol and the “non-responders” are those who have little or no effect.

One of the favorite parts of my job as a registered dietitian is to help my clients sort out how to meet their individual dietary needs.  Based on any health concerns, weight and their current diet, I can help them map out a dietary approach that may involve decreasing refined carbohydrates, such as sugars and starches, rather than limiting eggs.  Many of my clients eat too many grains and/or sweets and not enough vegetables.  Perhaps they eat large portions, or consume too much saturated fat from meat or added fats.  These habits can lead to overweight and diseases linked to inflammation – diabetes, heart disease and certain kinds of cancer.  Current thinking is that inflammation may be caused by insulin, carbohydrate intake and excess body fat rather than saturated fat or dietary cholesterol.  This means, cutting out egg yolks does not solve the problem.

That said, for my patients who have diabetes or heart disease and struggle with dyslipidemia, elevated cholesterol or high triglycerides, we may have to take the step of limiting or eliminating egg yolks.  But for healthy people who want to stay healthy, the right balance of vegetable, fruits, whole grains, lean meat and dairy and lean protein – including eggs – is the best approach.  In fact, limiting eggs in order to lower cholesterol is not going to help most people achieve greater health.  Rather, for many, it will deprive them of a convenient and inexpensive source of nutrients.

It has been said that strong recommendations about cholesterol and eggs have been made based on very weak data.  It may have been the best information we had at the time, but current information suggests we consider the bigger picture and make sensible adjustments according to individual dietary and health need. So thanks, Mom, you were right on this one after all.

“What’s For Dinner?” Wednesday: What Eggs And Avocados Have In Common

Baked eggs in avocado

This week’s recipe pairs eggs with a trendy fruit, the avocado (indeed- it’s a fruit, not a vegetable). Avocados, also known as “alligator pears” due to their pear shape and bumpy, green skin, have gained much popularity the past several years. Grocery stores, restaurants and food manufacturers are all embracing the healthy benefits of avocados, which are frequently offered as a side of guacamole or a sandwich topping, but also go well with eggs.

Avocados are touted for their high content of heart healthy monounsaturated fatty acids (MUFAs), but what many health professionals may be surprised to learn is that approximately 23% of egg’s calories are from MUFAs. According to the American Heart Association, when replacing saturated fats in the diet, “monounsaturated fats can help reduce bad cholesterol levels in your blood and lower your risk of heart disease and stroke.”

Interestingly, foods high in MUFAs, such as eggs and avocados, are typically sources of vitamin E as well, a powerful antioxidant which may help prevent or slow chronic diseases by reducing damage from free radicals. Vitamin E can be found in egg yolks along with many other beneficial nutrients.

Enjoy this week’s recipe, Tomato and Avocado Egg Salad, a delicious meal which delivers 9g of monounsaturated fat and 10% Daily Value of vitamin E per serving and is also an excellent source of fiber, folate and choline.

Ingredients:
6 HARD-BOILED EGGS, sliced
2 avocados, chopped
1 cup chopped tomato
½ cup chopped red onion
¼ cup chopped fresh parsley OR cilantro
Spinach OR lettuce leaves

Dressing:
2 Tbsp. mayonnaise
2 Tbsp. sour cream
1 Tbsp. fresh lemon juice
½ tsp. salt
¼ tsp. hot pepper sauce

Directions:
MIX dressing ingredients in small bowl. RESERVE and refrigerate 6 center slices from eggs for garnish. CHOP remaining eggs. COMBINE chopped eggs, avocados, tomato, onion and parsley in large bowl; toss gently to mix. ADD dressing; stir gently just until ingredients are evenly coated with dressing. REFRIGERATE at least 1 hour to blend flavors. SERVE on spinach leaves, garnished with reserved egg slices.

Nutrition Information:
Calories: 218, total fat: 17g, saturated fat: 4g, polyunsaturated fat: 3g, monounsaturated fat: 9g, cholesterol: 189mg, sodium: 316mg, carbohydrates: 10g, dietary fiber: 5g, protein: 8g, vitamin A: 867.9IU, vitamin D: 41.8IU, vitamin E: 3.2IU, folate: 89.6mcg, calcium: 51.0mg, iron: 1.5mg, choline: 139.8mg