With each issue, Trib+Health brings you an interview with experts on issues related to health care. Here is this week's subject:
David Earnest, Ph.D., is a professor in the department of neuroscience and experimental therapeutics at the Texas A&M University Health Science Center. Earnest focuses his research on the human biological clock. His most recent research has shown that saturated fats can reset people’s internal body clocks.
Editor's note: This interview has been edited for length and clarity.
Trib+Health: Can you explain your most recent research about fatty foods?
David Earnest: We’ve known for awhile, obviously, high fat foods, particularly saturated fats versus polyunsaturated fats, are bad for you in terms of metabolic disease. We know that a high-fat diet is a risk for cardiovascular disease, in terms of heart attacks and strokes.
I study biological clocks in the body that pretty much regulate the 24-hour timing of pretty much every process you want to look at in (human) cells. The general idea is that those clocks and that timing and regulation of our daily cycles are important because when things are not in the correct time, things start to go wrong.
What our study looked at specifically was whether or not saturated fatty acids, like palmitate, compared to an omega-3 fatty acid and a polyunsaturated acid called DHA. We wanted to look at how these saturated versus polyunsaturated fats affect our body clock and how they are affecting inflammation in cells. That is the major factor in how high-fat diets produce metabolic disorders like obesity and Type 2 diabetes.
There are two sort of critical observations in our study. The first observation that we saw was that at the time of the palmitate administration, in the case of humans and animals, the consumption really dictated how much inflammation was induced in the tissue.
Meals and snacks that are high in saturated fats are really going to increase the risk for metabolic disorders.
It’s not just what you eat in terms of avoiding saturated fats; it’s avoiding them at particular times during our cycles where they have the greatest effect. Not only do they have the greatest effect at night in terms of inducing inflammation, but at that time saturated fats are jet lagging our body clocks in our cells.
Trib+Health: How do we reset our body clocks if we’re having these problems?
Earnest: Normally, we don’t reset it. We mess it up. What’s going to reset it in humans is the light-dark cycle. What is the impact of the change of Daylight Savings Time? There, we actually have to reset your physical clocks, but at the same time what you really have to do to accommodate that is reset your body clock.
What really resets our clocks and keeps them synchronized are our social cycles or schedules and our work schedules.
Part of the problem here is that we have different things resetting our body clocks in different ways and unpredictable ways. What we’re seeing is that unsaturated fats are resetting the clock.
Trib+Health: What does your research mean for the average person walking down the street?
Earnest: I think it has a number of significant implications. Again, because of the epidemic of metabolic disease in the U.S., what it really says is that we need to approach metabolic disease in a fashion that we can manage — I’m not going to say prevent, but manage — and minimize the risks for metabolic diseases.
Trib+Health: Why did you go into this research area?
Earnest: I’ve been doing research in the area of biological clocks and their implications on human health and disease for about 30 years.
The twist in terms in terms of why I looked at saturated fats and high-fat diet is that some other researchers about five to 10 years ago had shown when you disrupt, reset or render our internal body clocks dysfunctional so that they’re not telling time anymore, that was directly linked to metabolic diseases. That’s the reason why I got interested in this specific area.
Trib+Health: What’s next for you with your research?
Earnest: What’s next, at least scientifically, is if we can better understand the mechanisms underlying this, then we can really can think about therapeutic strategies that involve what is a hot area clinically called chronotherapeutics. (Chronotherapeutics is a way of administering medical treatment to a schedule that fits a patient's daily biological clock to maximize health benefits.)
Disclosure: Texas A&M University is a corporate sponsor of The Texas Tribune. A complete list of Tribune donors and sponsors can be viewed here.