Precision nutrition, the practice of “nutrition as medicine,” creates personalized diets that factor in patients’ specific medical concerns.
Widespread adoption of precision nutrition is somewhat elusive, given the complexity of lifestyle and biological factors from patient to patient, along with cost and privacy concerns.
Technology can shed light on how DNA and the gut microbiome should determine diet.
Advancements in precision nutrition are paving the road to “nutrition as medicine.” Precision nutrition aims to develop highly personalized dietary recommendations, taking a tailored approach to virtually any medical concern, from weight management to cancer and autoimmune diseases.
As patients become more sophisticated in managing their health, the demand for this type of nuanced care increases. But are today’s patients hardened by failed attempts at customized diets and one-size-fits-all guidelines from the past?
Here’s the current state of precision nutrition, including what it can and can’t do for patients.
An overview of precision nutrition
Precision nutrition has gained significant traction in recent years—it means designing dietary recommendations based on an individual's unique genetic, metabolic, and environmental factors. Most of our present understanding of nutrition is meant for the general population.
But precision nutrition, says the Harvard TH Chan School of Public Health, rejects the idea that there’s one optimal diet for human health, as two people can respond differently to an identical diet.
While popular diets like the “blood type diet” have promised a higher level of tailored nutrition, they fail to stand up to scientific scrutiny. Nonetheless, some real progress toward personalized nutrition has been accomplished. The challenge lies in expanding this knowledge and applying it to patients.
Established foundations in human nutrition
Nutrient intake recommendations have been established for people in different stages of life, marking preliminary attempts at precision nutrition. According to the authors of a review in the Annual Review of Nutrition, these include Daily Recommended Intakes (DRIs) for 22 population groups, including infants, boys, girls, and pregnant women. Nutritional scientists have also defined “adequate intakes” to prevent deficiencies. Since the 1980s, the Dietary Guidelines for Americans have offered suggestions for food groups and, more recently, dietary patterns for public health.
As the review authors note, however, “less precision is required to prevent nutrient deficiency and toxicity states compared with chronic disease reduction.”
Although these standards offer a strong foundation for basic nutrition, there’s a need for more in-depth categorization and guidance.
Progress toward individualized diets
Examples of more personalized nutrition include the avoidance of lactose for lactose intolerance, gluten for celiac disease, and phenylalanine for PKU.
Additionally, some disease-specific recommendations have emerged, such as sodium restrictions for hypertension. However, despite knowing that certain people are responders or non-responders to this type of dietary intervention, so far, it hasn’t been practical to further classify individuals for specific diet prescriptions.
The gut microbiome is emerging as a critical player in precision nutrition. As the article by the Harvard TH Chan School of Public Health explains, variations in microbial composition influence how nutrients are absorbed and metabolized, with implications for issues like glucose control in type-2 diabetes. Tailoring dietary recommendations to support a healthy gut microbiome holds significant potential for personalized nutrition.Related: Exploring the relationship between gut health and neurodegenerative disease
In addition, technologies like genome sequencing have enabled substantial progress in understanding how genetics influence disease risk. Identifying genetic predispositions and learning how DNA affects metabolism can help further the goal of precision nutrition.
Modern-day challenges and considerations
Today’s health experts are tasked with optimizing nutritional approaches for population subgroups beyond the bounds of isolated geographical locations. Historically, human genetics and microbiomes have adapted to localized food conditions and availability. However, globalization of the food supply and of the human population requires specialization for evolving biological and lifestyle traits.
Despite promising strides, several challenges and limitations must be overcome before the fruits of precision nutrition are realized in practice.
The interplay between genetics, environment, and lifestyle factors is incredibly complex. Precision nutrition must also account for socioeconomic factors, cultural dietary practices, and psychological aspects of eating behavior.
In addition, long-term health outcomes and the sustainability of personalized dietary plans require further investigation.
Considerations like privacy and the cost of genetic profiling and advanced metabolomic analysis restrict the robust research needed to support evidence-based practice. However, with the expansion of smarter technology and tracking tools, precision nutrition should only continue to improve. While 100% precision may always be a pipe dream, any level of progress is to be celebrated.
What this means for you
Patients want tailored nutrition, but the data isn’t there to offer fully evidence-based individualized diets just yet. While progress is ongoing, it’s important to recognize the limitations of what we know. Communicating realistic expectations can help build trust in patients who may feel betrayed by the diet industry, keeping the door open for truly tailored nutrition in the future.