(P22-059-25) A Low-Ultra-Processed, Plant-Forward Diet With Lean Red Meat Enhances Metabolic Health in Older Adults at Risk for Insulin Resistance – A Feeding Intervention

Objectives: Higher red meat intake has been associated with an increased risk of type 2 diabetes, yet most studies do not differentiate between processed and minimally processed red meats. We hypothesized that a healthy, plant-forward, low ultra-processed diet with minimally processed lean pork (MPLP) can improve nutrient adequacy and metabolic functions in older adults.

Methods: Over 8 weeks, the feeding study provided a ~2000 kcal/d diet (%carbohydrate:%fat:%protein = 54:28:18) including 162 g/d of MPLP, to 36 overweight, borderline insulin-resistant, non-diabetic adults (mean age: 72 years). All meals were freshly prepared with minimal use of artificial ingredients and added sugars, while incorporating plant foods at every main meal. Participants completed dietary recalls, surveys, and provided biological samples before and after the intervention as well as after one year. Data were analyzed in R using linear mixed effects modeling.

Results: Compared to the baseline diet, the intervention diet was lower in total fat (-12.2%), sodium (-16.9%), saturated fat (-6.1%), and ultra-processed foods (UPF, -38.1%) while doubling fiber intake. Average daily energy intake spontaneously decreased from 1983 ± 866 kcal to 1650 ± 334 kcal post-intervention. Metabolic improvements included HOMA-1IR (-18.74%, p< 0.0001), QUICKI (+5.28%, p= <0.0001), SPISE (+6.29%, p= 0.01), TyG index (-1.28%, p=0.03), glucose (-2.93%, p=0.01), insulin (-15.86%, p< 0.0001), C-peptide (-14.36%, p< 0.0001), total cholesterol (-10.57%, p< 0.0001), LDL (-6.76%, p=0.006), non-HDL (-7.36%, p=0.002), ApoB (-11.63%, p< 0.0001) and a concomitant 81.5% (p=0.03) increase in FGF21—a key regulator of glucose and lipid metabolism. One-year post-intervention follow-up data showed a rebound in energy, fat, sodium, and UPF intakes alongside a reverse trend in metabolic status: SPISE (-3.53%, p=0.06), TyG index (+2.3%,p=0.003), glucose (+10.78%, p< 0.0001), total cholesterol (+9.02%, p=0.0004), LDL (+10.49%, p=0.02), and non-HDL (+10.68%, p=0.004)

Conclusions: A healthy, plant-forward, low-UPF dietary pattern with MPLP enhanced nutrient intake patterns, spontaneously reduced energy intake and improved glucose and lipid metabolism supporting healthier aging in older adults. MPLP can be part of a healthful diet without negative impacts on metabolic health.

Funding Sources: National Pork Board