Egg Nutrition Center Blog

UConn Professor, Dr. Maria-Luz Fernandez, Highlights her Recent Research

Breakfast Tacos

The Egg Nutrition Center interviewed Dr. Maria-Luz Fernandez, a nutrition researcher at the University of Connecticut. For many years, Dr. Fernandez has studied the impact of diet on various health indices in Hispanic and non-Hispanic subjects. She has done feeding studies in Mexico, and has a keen sense of the health and nutrition issues that impact the Hispanic community. We asked Dr. Fernandez about the role of eggs in the Hispanic household, as well as for an update on some of her latest research. Below are her responses to our questions: 

ENC: Eggs have always been an important staple in the diet of many Hispanic cultures.  Per capita egg consumption in Mexico, for example, is much higher than it is in the United States. Why is that?
Dr. Fernandez:  In Mexico, eggs are considered a nourishing and filling breakfast. It is very common to see households across the economic spectrum consume eggs for breakfast. I use the plural “eggs” because people normally consume 2 and it is not uncommon for some folks to consume 3 or more. Eggs are very much considered a staple and a traditional food among Mexicans.

ENC: You have conducted a lot of health/nutrition research both in the United States and in Mexico. What is the primary focus of your research? What have been the general findings of your work?
Dr. Fernandez: The primary focus of my research is to investigate how foods or dietary patterns can decrease risk for heart disease. I have conducted a lot of studies with eggs in different populations. In spite of the fact that the new 2015 dietary guidelines released in January removed the 300 mg daily cholesterol limit, eggs and other cholesterol-containing foods continue to be somewhat controversial.  I don’t believe that this should be the case. In my work and the work of many others, eggs are not associated with higher risk for heart disease. In fact, eggs actually increase biomarkers associated with reducing cardiovascular risk. I have worked with numerous populations: children, young adults, the elderly, overweight/obese individuals, people with metabolic syndrome and most recently with patients with diabetes. In all of these studies, the major conclusions are that the LDL/HDL ratio, a biomarker of heart disease, either decreases with egg intake or does not change. One other consistent finding has been that eggs raise HDL cholesterol and make this form of cholesterol more effective in its role of reverse cholesterol transport, which lowers CVD risk.

Further, eggs increase the levels of lutein and zeaxanthin in plasma, two carotenoids that are recognized as having both anti-oxidant and anti-inflammatory effects, and they increase plasma choline, an important nutrient associated with cognitive function.

Most recently, we have done measurements of plasma trimethylamine-oxide (TMAO), a purported marker of atherosclerosis that can be increased by dietary choline intake and we found no effect of consumption of 3 eggs per day for extended periods of time on plasma TMAO levels. Overall all my studies have demonstrated that eggs are a complete food, which can protect against heart disease and that also contributes significantly to the daily nutrient intake of vitamins and minerals as well as high quality protein.

ENC: Overall, are primary health concerns in Hispanic populations very different than those that we see in other cultures? What are the major disease issues that affect Hispanics in the United States?
Dr. Fernandez: One of the main health issues among Hispanics is diabetes. Diabetes has a strong genetic component in Hispanics; thus it is very important to understand how different foods can affect patients with diabetes. Since there seems to be a controversy between eggs and diabetes, we conducted a clinical study in Mexico with patients with diabetes who consumed eggs.  Subjects consumed either 1 egg per day for 5 weeks or a bowl of oatmeal for 5 weeks as breakfast in a crossover design in which each individual served as his/her own control. We concluded that biomarkers associated with heart disease or diabetes did not change and they were similar after the two breakfasts. However, liver enzymes and inflammatory markers were lower after the egg breakfast, suggesting a protective effect of eggs against inflammation. More studies need to be conducted with 2 or 3 eggs per day for extended periods of time in diabetic people to further assess these findings with higher egg consumption.

ENC: What impact does lifestyle have on the health issues most prevalent in Hispanic communities?
Dr. Fernandez: I think that maintaining a healthy weight is very important for the Hispanic community and for that matter, for the whole population. Maintenance of a healthy body weight prevents the development of metabolic syndrome, heart disease and diabetes, not to mention immune function, cancer and others. One way that Hispanics can maintain healthy body weight is by consuming less carbohydrate and sugar-rich foods and by increasing the number of hours of exercise per week.

ENC: Are eggs an important part of your diet at home?
Dr. Fernandez:  Yes, they are. We eat eggs for breakfast, especially in omelets with vegetables including broccoli, tomatoes, onion and mushrooms. We normally accompany them with hot salsa and a piece of bread or one tortilla. This breakfast keeps me satisfied for several hours and decreases caloric intake for the rest of the day.

ENC: Any general health/diet advice for folks in the Hispanic community seeking to eat healthier foods?
Dr. Fernandez: I would say reduce consumption of sodas (especially regular sugar) and sugar-rich foods, consume more vegetables and have eggs for breakfast to decrease your appetite for the rest of the day. Eat eggs with vegetables and not with fatty meats.  Increase fish intake as well. As mentioned earlier, it is important to maintain a healthy body weight and by doing this, you can minimize risk of developing many of the chronic diseases that impact the Hispanic community.

Author: Rachel Bassler, RDN, CSSD, LDN