Will you succeed or fail on a ketogenic diet? Will exercise be more important than food choices if you want to lose weight? The answer to these questions may lie in your genes. Genetic analysis is contributing to a growing area of nutritional medicine that offers diet recipes, including personalized diet plans based on nutrigenomics, to help people make more informed decisions about their lifestyle habits and their health. .
The Cleveland Clinic has been providing personalized nutrigenomic testing for several years. As a dietitian there, I can see first-hand the benefits it brings to patients. It is especially helpful for patients who have found themselves "stuck" in their weight loss efforts. Having a genetic insight into the types of diets that work best for them often increases both compliance and sustainability.
I identify five of the most important genes to focus on with my patients based on their goals. This may involve changing the type of training they are doing, altering the percentages of fat and protein in their diet, suggesting specific supplements, such as methylated folate or vitamin B12 or customized vitamins, and increasing certain nutrients from food, such as vitamin A or iron. Often my recommendations are also in line with the patient's supplemental laboratory data.
What is nutrigenomics?
A relatively new scientific discipline, nutrigenomics focuses on the relationship between genes, nutrition, and health. It seeks to explain how our bodies respond to what we eat and drink, and how we can use that knowledge to promote activity in our "good" genes and suppress it in "bad" genes. Nutrigenomics-based diet plans are based on an analysis of your genetic makeup to inform dietary recommendations that meet your personal health and nutritional needs and help prevent nutrition-related chronic diseases.
"The ultimate goal of nutrigenomic testing is to identify subgroups of populations that may respond to diets differently or display different food intolerances or susceptibility to disease," said Dr. Lu Qi, associate professor of nutrition at Harvard T.H. The nutrition department at the Chan School of Public Health told TODAY in an email. "That goal is promising and is increasingly supported by scientific evidence, including from our studies." Qi explained that this kind of personalized approach is expected to improve the effectiveness of dietary recommendations. However, he said, “Nutrigenomics research is still in its infancy. At this stage, it is more important to accumulate evidence than to generate recommendations. "
The science behind custom testing
Multiple studies have shown that genetics come into play with our eating habits. Research also suggests that knowing our genetics can influence how well we adhere to dietary prescriptions. For example, a 2014 randomized controlled trial showed that participants who possessed the risk variant of the ACE gene (a gene that directs the body on blood pressure levels) were able to significantly reduce their sodium intake compared to the control group ; they also maintained their lowest sodium intake a year later.
Another study published last month in the British Medical Journal showed that people who received nutrigenomics-guided dietary advice for total fat and saturated fat intake significantly reduced their long-term intake compared to population-based baseline interventions. .
However, other studies have suggested that gene-based dietary interventions may not be as promising as previously thought. Results from a randomized clinical trial for DNA diet test that followed more than 600 overweight adults over a 12-month period found that a genotypic feeding approach was not "associated with the dietary effects of weight loss."
While the concept may have potential, more research is needed to affirm the efficacy of gene-based diets. Qi stressed that a balanced diet, exercise, and adequate sleep benefit everyone, regardless of their genomic makeup, but suggested that certain subgroups are likely to be more sensitive to different diets: a low-fat versus a high-fat diet, for example, or certain specific exercise regimens. "However, the current evidence is still far from sufficient (for physicians or dietitians) to provide practical guidelines," she said, "and personalized recommendations will be based on the accumulation of data in the future."
The possible benefits of a DNA-based diet
The ability to customize diet and exercise plans based on an individual's genetics may be the next frontier in nutritional counseling. A personalized diet plan can help increase compliance, as well as help you reach dietary and physical activity goals that are more in line with what works for your body.
"While it is important to follow food and nutrition guidelines set by government agencies, evidence has shown that such one-size-fits-all nutritional recommendations can be ineffective and often ineffective," said Dr. Ahmed El-Sohemy, professor. and Canadian Researcher President of Nutrigenomics at the University of Toronto and Founder and Chief Scientific Officer of Nutrigenomix, Inc., a company that performs genetic testing for personalized nutrition.
Dr. Christopher Lynch, director of the Office of Nutrition Research at the National Institute of Diabetes and Digestive and Kidney Diseases, said TODAY in an email that the NIDDK's new 2020-2030 Strategic Plan for Nutrition DNA Test Research will be focuses on the unifying theme of precision nutrition, which focuses on personalized, DNA-based eating plans and includes nutrigenomics. "There are many factors affecting individual responses to diet, including learn more DNA diet-gene interactions, that must be taken into account when developing comprehensive and dynamic nutritional recommendations relevant to both individual and population health," he said. Lynch also emphasized that "more research is needed to fully understand the impact of these factors and their interrelationships."
Are Nutrigenomic Tests Right For You?
"Genetic variation is an important component of why people differ from each other in their metabolism," Dr. Steven Zeisel, director of the University of North Carolina Institute for Nutrition Research and founder, told TODAY in an email. from SNP Therapeutics. "Genetic testing and nutrigenetics have a lot to offer, but they may not be ready yet to tell someone what diet will make them lose weight."
Aside from the fact that the research is still in its early stages, nutrigenomic testing is not cheap, so cost can be a concern. The price for a test and analysis starts at around $ 300. Privacy is another common concern. "Some people may be concerned that their genetic information could be used to discriminate against them at work or with their health insurance coverage," El-Sohemy said. But he also noted that the "Genetic Information Nondiscrimination Act (GINA) became law in May 2008 and provides federal protection against such discrimination."
There are dozens of tests on the market that provide analysis of the genes involved in nutrient metabolism and response, including Ancestry and 23andMe, but once you receive the results, you still need to find a specialist to analyze the raw data and make recommendations. If you're interested in learning more about DNA diet testing, talk to your doctor about getting a referral to a reputable medical group that offers nutrigenomic testing.