The Big Picture
Ordovás says we shouldn’t forget that other factors, such as beneficial gut microbes, also play an important part in questions of nutrition and the delicate balance between health and disease, which explains the rising popularity of probiotics. (A healthy microbiome is perhaps best encouraged by diets including plenty of plants. See “Change Your Microbiome, Change Yourself” in the spring 2014 issue of Genome for more on this topic.) While the field of nutrigenomics goes back almost three decades, progress has been slow. But Ordovás has grown “mildly optimistic” in recent years that a clearer picture might begin to take form.
“Nowadays, we have the technology, and we have substantially increased our knowledge about the genome,” he says. “However, we were missing an important component: the huge number of subjects needed to carry out solid gene-diet interaction studies.”
Ordovás began his work many years ago by taking advantage of long-term studies involving 3,000 or 4,000 people. What’s needed from a statistical point of view are studies involving at least 10 times those numbers. “Before, we were doing the work,” he says, “but we didn’t have the power to come out with results that were convincing.”
He points to the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) Consortium, based on a collection of independent, relatively large, and long-running studies, as one new and hopeful example of where the science needs to go. There are challenges to overcome to quantify what food people eat and what’s really in that food, and Ordovás says, from his perspective, “we are still at the very early stages of the journey.”
James Kaput, head of the Clinic Translation Unit at the Nestle Institute of Health Sciences in Lausanne, Switzerland, and the former director of the Division of Personalized Nutrition and Medicine at the FDA National Center for Toxicological Research, is also working hard to put the nutrigenomics puzzle pieces together. Kaput is advocating for a systems approach to nutrition, involving genomic analysis together with measures of comprehensive nutrient profiles and more.
“Many studies don’t consider that not all people are the same and will respond differently to foods. The idea that everyone will respond positively to any type of nutrient is probably incorrect.”
No one really knows how many “essential nutrients” there are, he says, but he and other Nestle scientists are working to develop the capability to capture profiles representing 100 important nutrients. That’s in contrast to most studies done so far, which often focus on one nutrient at a time.
So far at Nestle, he has expanded a study begun while at the FDA to characterize the nutrient status in kids attending a community day program to include populations representing various parts of the world. In a broad sense, he says progress will require that more nutrition studies incorporate genetics and more genetics studies incorporate nutrition, along with other aspects of the environment.
“I think if we don’t include genetic makeup as a part of studies, which is what we’ve been promoting in the nutrition community for 30 years, I don’t think we will ever go forward in understanding causal mechanisms for why you respond the way you do,” Kaput says.
Thankfully, Urben didn’t need to wait for the science to progress any further. As tricky as her condition and its causes may be, her solution for feeling better isn’t risky or complicated: “You’ve got to get back to basics,” she says. “Get all the processed junk and chemicals out of our lives.”
That sentiment and Urben’s diet call to mind the famous and infinitely simple (if not always simple to pull off) advice of Michael Pollan, the best-selling author of many books, including The Omnivore’s Dilemma, Food Rules, and Cooked: “Eat food, not too much, mostly plants.” By food, Pollen doesn’t mean “edible, foodlike substances,” but recognizable, whole foods that don’t come with a list of mystifying ingredients.
On the other hand, manufactured foods are a fact of life for many people, and understanding how human bodies — representing people all around the world — respond to nutrients, and respond to them differently, could be key in making them that much better.