Does junk food lower sex drive?

Interview with Jaume Ferrer Lalanza

You are probably trying to limit foods high in fats and sugars or junk foods in your diet to avoid being overweight, and you are absolutely right.

Dr. Jaume Ferrer Lalanza eating junk food!

The truth is that junk food not only affects our body, but also our brain. Junk food has shown to have anxiolytic and antidepressant effects on animals placed in high stressful states. This might be the reason why watching a movie with your favorite junk food appears to be an easy solution for emotional troubles. Eating junk food may temporarily distract your attention from life problems but it doesn't solve stress causes. What is even more interesting, is that chronic consumption of junk food products reduces some mechanisms of the reward system and could decrease the preference for other rewards review about the effects of junk food: Link).

But, could junk food even lower the desire for sex?

To get the answer, we interviewed Jaume Ferrer Lalanza is a postdoctoral researcher at The Arctic University of Norway (UiT)’s Behavioral and Translational Neuroscience group, where he investigates the risks of excessive junk food consumption on the brain reward system. Before coming to UiT, he studied the effects of lifestyle on brain function and health while completing his PhD in Health and Sport Psychology at the Universitat Autonoma de Barcelona (UAB).

Pint of Science: Jaume, does junk food lower sex drive?

Jaume: As you already know, excessive junk food consumption causes obesity and negatively affects the reward system, and may reduce the preferences for other rewards. High-fat diets and obesity are able to affect reproductive functions, and obesity is a risk factor for infertility in both women and men. Therefore, it is possible that junk food also affects sexual behavior. However, scientific data regarding this topic is very limited and we cannot determine the effects of junk food on sexual behavior. Maybe I could give you a better answer after I complete my current research.

PoS: Can you tell us a little bit more about your current project?

J: We are looking for the neurological mechanisms that make consuming junk food negatively affect the reward system. Specifically, the neuronal and behavioral changes in sensitivity to rewards beyond conditioned food and sex rewards. In other words, in our project, we want to study how the brain is able to process other natural rewarding stimuli like sex when it is fed up with junk food, which is also rewarding for us. The project that I am working on as a postdoctoral researcher is about junk food and the brain’s reward system and is EU-funded by a Marie-Curie fellowship (Link).

PoS: How did you come up with this project?

J: As you already know, obesity is one of the greatest public health challenges of the 21st century. Overweight and obesity have reached epidemic levels and their prevalence is increasing every day. Junk food consumption is one of the major causes. It is surprising that although most of the population knows the unhealthy risks of junk food overeating, a lot of people just cannot stop eating junk food. Therefore, we suspect that this type of food could affect not only our metabolic system, but also our brain and the neurological mechanisms that process rewarding stimuli, from motivation to pleasure.

PoS: So, why is your research important and what are the possible real-world applications?

J: Our project will help to understand why junk food is overconsumed in our society. It is the first step to establishing political measures to regulate the junk food industry, its consumption and distribution. For example, if we find that junk food changes the neurological basis of reward processing, governments could pressure the food industry to reduce the amount of fat and sugar, ban certain products in school canteens or increase taxes on junk food. In some countries there are already taxes on sugar beverages.

Knowing how one reward affects the processing of other rewards in general increases our understanding of the reward system. It will also help to improve therapies for weight-loss and even for substance use disorders. For example, the results of this project could shed light on people’s difficulties to follow a caloric restriction diet, because maybe it is not only about calories but about pleasure.

PoS: What’s your assessment on the current state of “Junk food addiction is comparable to drug addiction”?

J: This is a hot topic without a clear answer and diversity of opinions among the scientific community. On the one hand, the effects of junk food on the dopaminergic system, the system that activates reward sensations during various, usually pleasant activities, could suggest that excessive consumption of junk food exerts similar effects on the brain as drug abuse (I recommend this review to know more about it: Link). On the other hand, the clinical criteria for substance use disorders are sometimes difficult to apply to junk food and there are several significant differences between, for example, cocaine and “junk food addiction” at the clinical level. I also recommend an interesting scientific editorial written by one scientist in favor of the food addiction theory and another against it (Link).

PoS: What excites you about your work?

J: The best part of my work is being able to answer intriguing questions about our brain and our behavior. Why do we do this or that?

Of course, with each research project, we can only find a small piece of the puzzle of human behavior and its neurophysiological mechanisms. However, when all scientific communities work together, our knowledge grows exponentially and human-kind advances and evolves toward a promising future. I really like being part of it. And of course, I like working in the laboratory: studying new techniques and formulating new hypotheses based on the previous work from my colleagues.

PoS: And, what would you like to improve in your work or in the scientist’s work in general?

J: I would like to take the opportunity to highlight that science is not a hobby and is not as easy as it appears at first glance. From my point of view, the scientific career should be professionalized with better working conditions. Here in Norway, fortunately, scientists and researchers have a good working environment and conditions, but this is not the rule for other European countries. The bad working conditions and lack of job security that many young researchers face hinders a balance between a working and family life and increases the prevalence of mental disorders (Link).

PoS: This is unfortunately true and important to be highlighted. The last question is not about science. We are simply curious to know what you like to do when you aren't working on research?

J: Scientists are not strange people, some of us have regular routines and others have exciting lives. Maybe it could sound rare, but my passion outside academia is the automotive world and who knows, perhaps in the future I could combine “psychological science and cars”. Another of my hobbies is sport, I love cycling and after living in Tromsø, cross-country skiing as well. I also enjoy a good novel with a glass of wine and taking pictures from my adventure travels.

So yes, I’m pretty an average guy that you could find in the supermarket or in a pub, but instead of working in an office or driving a city-bus, I go every day to a laboratory at the university.