In this interview, News-Medical speaks to Dr. James Shikany about diet and how different diets can affect your risk for cardiac death.
Please could you introduce yourself and tell us what inspired your research into diet?
I am James M. Shikany, DrPH, FAHA. I am the Oberman Endowed Professor of Medicine and Associate Director for Research in the Division of Preventive Medicine in the School of Medicine at the University of Alabama at Birmingham.
I have always been interested in the connection between what people eat and the risk of chronic disease because diet is something that we have control over.
Food. Image Credit: G-Stock Studio/Shutterstock.com
Food is vital, providing the nutrients we need for a healthy life. Why is research into food and the impacts of different diets on our health so important?
Well, as I mentioned, I think it is important because we have control over what we eat – diet is a risk factor for disease that we can modify. But in order to do that, we obviously need to know what the optimal diet (or diets) is.
Well-conducted research into the association between diet and disease is how we increase our knowledge of what constitutes a healthy diet.
Sudden cardiac death occurs in 1 in every 7.5 deaths in the US. Why is this and what could be done to help prevent this statistic from increasing?
Sudden cardiac death can be the actual cause of death, such as occasionally occurs in a seemingly healthy person who has the sudden onset of an abnormal heart rhythm and dies (unless treated within a few minutes) because the heart loses its ability to pump blood to the rest of the body, especially the brain.
More commonly, sudden cardiac death occurs as a result of a heart attack in the setting of coronary heart disease (blockages in the coronary arteries). In this case, the blood supply to the heart is compromised which can lead to fatal rhythm disturbances.
Coronary heart disease remains all too common in the US, and to reduce its prevalence, we must reduce the associated risk factors, including an unhealthy diet.
Please could you give an overview of both the Southern and Mediterranean diet? What foods consist in both of these diets?
The “Southern” dietary pattern includes a heavy reliance on foods that are part of the traditional Southern diet – added fats, fried foods, eggs, and egg dishes, organ meats (e.g., liver), processed meats (e.g., hot dogs and bacon), and sugar-sweetened beverages.
The Mediterranean diet relies heavily on olive oil, vegetables, fruits, legumes, unrefined cereals, and fish, along with moderate consumption of dairy products.
Southern Diet. Image Credit: Monkey Business Images/Shutterstock.com
How did you carry out your latest research into the Southern diet and cardiac death?
We utilized the ongoing REasons for Geographic and Racial Differences in Stroke (REGARDS) cohort to study the possible associations of the Mediterranean diet and various dietary patterns with the risk of sudden cardiac death. Diet was assessed in REGARDS participants when they entered the study in 2003-2007.
We calculated the Mediterranean diet score and derived five dietary patterns from these dietary intake data collected at baseline. We then followed the participants for approximately 10 years, asking them or family members every 6 months about the occurrence of various cardiovascular diseases, including sudden cardiac death.
Reported cases of sudden cardiac death were confirmed by experts using medical records. We then conducted statistical analyses to see if adherence to the Mediterranean diet or any of the dietary patterns was associated with a higher or lower risk of sudden cardiac death, after adjusting for other known risk factors.
What did you discover? Was there anything in your results that surprised you?
Overall, we found that over 10 years of follow-up, those participants who had the highest adherence to the Mediterranean diet had a 26% lower risk of experiencing sudden cardiac death compared to those who showed the lowest adherence to this diet.
Participants who had the highest adherence to the Southern dietary pattern had a 46% higher risk of experiencing sudden cardiac death compared to those who showed the lowest adherence to this dietary pattern.
Surprisingly, in participants with a history of coronary heart disease (the type of heart disease that can lead to a heart attack) when they started the study, those who had the highest adherence to the sweets dietary pattern (desserts, candy, sweetened breakfast cereals) had a lower risk of sudden cardiac death. We have no viable explanation for this counterintuitive finding.
What advice would you give to people to help them lower their risk for sudden cardiac death?
Although our results need to be corroborated in other studies, I feel confident in advising people to reduce the amount of meat in their diet, especially processed meats, consume fish once or twice a week, increase the amounts of fruits and especially vegetables, and reduce the amounts of sweets and sugar-sweetened beverages.
I think those recommendations would lower the risk for a variety of diseases, not just potentially sudden cardiac death.
Do you believe that by raising continued awareness of certain diets, we can help people to lower their risk for cardiovascular diseases?
Certainly. I believe that the more information we can provide the public about which diets are associated with a lower risk of cardiovascular disease, the greater chance we have of seeing benefits. Of course, the most difficult part of this is getting people to actually make the changes in their diets.
Having the information on what a healthy diet is certainly is an important first step, but translating that into actual dietary changes is the challenging part, in part because eating has a significant emotional component.
Heart Health Concept. Image Credit: Brian A Jackson/Shutterstock.com
In light of the ongoing COVID-19 pandemic, why is it more important than ever to encourage people to adopt a healthy diet?
I always encourage people to have a healthy lifestyle to help mitigate the impact of disease. This includes a healthy diet, regular physical activity, and adequate sleep.
Why is it also important to look into the societal factors involved in healthy eating?
It is important because just having the information on what constitutes a healthy diet is not enough. Do people have access to fresh fruits and vegetables in their neighborhoods? Can they afford to eat fish once or twice a week? Are unhealthy foods too cheap, incentivizing people to consume these? These are all important factors that can influence a person’s ability to consume a healthy diet.
These questions, and many others, must be considered, but this goes beyond what I do as a nutritional epidemiologist.
What are the next steps in your research into diet?
We will seek to corroborate these results in other cohorts – that is part of the scientific process. I also am actively involved in investigations of diet with other chronic diseases.
Where can readers find more information?
The American Heart Association is a reliable source of information on diet and heart disease, including information on the Mediterranean diet (www.heart.org).
About Dr. James Shikany
Dr. James M. Shikany is the Oberman Endowed Professor of Cardiovascular Disease and Associate Director for Research in the Division of Preventive Medicine, School of Medicine, the University of Alabama at Birmingham (UAB). He arrived at UAB in 1993 after earning a Public Health doctorate, with a specialization in nutrition, from the UCLA School of Public Health. Besides his primary appointment in the Division of Preventive Medicine, Dr. Shikany has a secondary appointment in the Department of Epidemiology of the UAB School of Public Health.
Dr. Shikany’s professional efforts have been in the areas of epidemiologic and clinical research. His research interests are wide-ranging, but center on the association of diet and chronic disease, including cancer and cardiovascular disease. He has current and previous research funding from the National Institutes of Health, Department of Defense, American Heart Association, and American Cancer Society. He has performed several scientific activities on a national level and was elected Fellow of the American Heart Association in 2016.
Dr. Shikany was the recipient of the Max Cooper Award for Excellence in Research in the Department of Medicine of the UAB School of Medicine in 2016. Dr. Shikany has authored more than 260 publications in peer-reviewed journals and has delivered numerous scientific conference presentations in the area of nutrition and chronic disease.