Precision Nutrition Impact on Health-Related Behavior Change

A prospective, randomized, controlled trial enrolling up to 150 service members (SMs) from two sites; Joint Base Lewis McChord (JBLM) in the Northwest and Joint Base San Antonio (JBSA)-Lackland in the Southwest. A baseline genomic profile (70 genes/80 single nucleotide polymorphisms \[SNPs\]) augmented by common serum biomarkers specific to diet-related chronic disease (metabolic syndrome, cardiovascular disease \[CVD\], vitamin D deficiency) risk will be created. Subjects will be randomized to either personalized nutrition counseling or standard nutrition education for 6 weeks. This interval matches Service-run healthy weight initiatives such as the Army's current Fit for Performance Program. To promote self-care and engagement, a digital app will be utilized for 2 weeks for real-time health data capture with continuous feedback and will be validated with in-person RD interviews. Physical activity and injury data, sun exposure, and family history will help elucidate unique individual responses. Participant follow-up at 12 weeks will evaluate changes in anthropometrics and metabolic, cardiovascular, and vitamin D biomarkers.

Precision nutrition leverages the specificity of molecular and phenotypic differences in personalizing diet and lifestyle interventions. Specific Aims: 1) Examine the effectiveness of gene-based nutrition counseling on health-related behavior change in service members as measured by body weight, body mass index (BMI), blood glucose, lipids, 25-hydroxyvitamin (OH) D, %body fat (BF), waist circumference, and blood pressure; 2) Evaluate the feasibility of a digital application to accurately capture diet, activity, and sleep behaviors; and 3) Describe military-unique characteristics in demographics, diet, and lifestyle for northwest Army and southwest Air Force cohorts.

A baseline genomic profile will be created from 70 diet-responsive genes and 80 variants following amplicon sequencing on an Illumina MiSeq platform and will be informed by serum biomarkers specific to diet-related chronic disease risk (i.e. metabolic syndrome, vitamin D deficiency) for each subject. Risk variants were selected if minor allele frequency \> 5% and at least two published papers verified the link to the phenotype of interest. Treatment group receives gene-based nutrition counseling for six weekly sessions; Controls receive evidence-based nutrition pamphlets, all content directed at preventing metabolic syndrome. A digital app provides real-time health data capture with continuous feedback and is verified by in-person dietitian interviews. Both groups will also use study resources independently for six weeks, returning for final body composition and serum biomarkers after the twelve-week intervention. The control group receives the genomic profile with dietary recommendations upon study completion. Data analysis will examine between-group and by-cohort differences on primary anthropometric and biomarker outcomes.

Eligibility Criteria:
Inclusion Criteria:

* Active duty Army or Air Force
* Age 18-45
* Able to read and comprehend English
* Assigned to JBLM or JBSA-Lackland,
* Remaining on station for 5 months
* Consider self generally healthy
* History of or currently out of compliance with military fitness standards
* Willing to submit 2 blood samples including one for gene testing
* Willing to undergo 1 DEXA scan (JBLM only)
* Willing to participate in 6 weekly nutrition counseling sessions if assigned to treatment group

Exclusion Criteria:

* Currently diagnosed with an eating disorder
* Pregnant
* Current physical training profile (ie limitation)
* Pending deployment in next 5 months
* Pending retirement in next 5 months
* Pending permanent change of duty station in the next 5 months
* Currently has a pacemaker (contraindicated for bioelectrical impedance analysis)