Food for Thought

Would viewing food as ‘a cocktail of hormones’ deliver a better diet for weight loss and health?  
The search for the perfect diet – one that promotes weight loss and optimal health – has left many people empty handed. In a Perspectives piece in Science, University of Cincinnati researchers, Prof Randy Seeley and Dr Karen Ryan, suggest that the ‘big picture’ macronutrient focus on high-fat or processed carbohydrate-rich diets could be misplaced. They suggest that it might be time to dig deeper and look more closely at the micronutrients that act at the cellular level. Why? Well, our bodies’ cells talk to each other in a complex language of chemical messages and some of those chemicals come from the food we eat. It’s the problems in cell communication that can lead to diseases such as diabetes and cancer.

What Seeley and Ryan are suggesting is that we should view food as if it is a “cocktail of hormones” because of the way its derivatives (the micronutrients) act on cells within the body. Take the micronutrient leucine (an amino acid) for example. It has been found to trigger brain pathways that reduce food intake and body weight. However, we need to get it from foods like soybeans, some cuts of beef, brown rice, chicken egg yolks and cow’s milk as our bodies don’t make it.

Seeley reminds us that what we eat is not just made up of various amounts of fat, protein and sugar/starch. He says, ‘As food is broken down, its micronutrient components circulate in the blood and act on cell-surface receptors on multiple organs to change the activities of those cells in the same way that hormones made in our body do. In this way our bodies can listen and respond to what foods we are eating.’

The authors write: ‘Viewing food as a hormone could substantially influence how we make dietary recommendations to promote health or treat specific diseases. Rather than using only nutritional epidemiology to identify what healthy people consume, we may be able to design diets from the bottom up – based on their ability to alter signalling pathways in specific tissues that we know are linked to metabolic disease. In addition, this framework suggests that the argument over whether fat or sugar is to blame for the increasing incidence of obesity may be misguided. Macronutrients are classified by their energy-yielding biochemical properties, not by their ability to activate receptors in a manner similar to that of a hormone. It may be more productive to examine the signaling properties of a given diet to understand whether it will promote weight gain or weight loss. Identifying these food – and food metabolite – receptor interactions will provide new opportunities to understand the relationship between what we eat and diseases including obesity.’

‘Designing a diet based on how its various micronutrients turn on or off certain receptors in different tissues is a bottom-up way to design diets. Just as different levels of various hormones can influence our health, so can the “hormones” that come in from our food,’ says Seeley.

What are micronutrients? As the name suggests, micronutrients are substances found in foods and drinks that are essential for life, but they are only required in relatively small amounts. For example, vitamins and minerals are micronutrients as they only make up a tiny portion of the food we eat, but in many ways they are just as important for the body as macronutrients (fat, carbs, protein etc). Together with water, our bodies need micronutrients for the release of the energy as well as other aspects of chemical changes.

– Prof Randy Seeley is Donald C. Harrison Endowed Professor, Director, UC/CCHMC Center of Excellence in Obesity and Diabetes. His work has focused on the actions of various peripheral hormones in the CNS that serve to regulate food intake, body weight and the regulation of circulating fuels. In particular, he has focused upon the numerous hypothalamic and G.I. peptides and their associated receptors that influence both energy intake as well as peripheral metabolic processes. You can contact him on: randy.seeley@uc.edu