Adopting, Abandoning, and Re‐adopting Healthy Eating Patterns Sends Cardiovascular Disease Risk Factors on a Rollercoaster Ride

Abstract

The 2015–2020 Dietary Guidelines for Americans encourages people to adopt a healthy eating pattern (HEP) for disease prevention. The Dietary Approaches to Stop Hypertension (DASH) diet and the Mediterranean‐Style Eating Pattern (Med) are representative of HEPs and are known to improve cardiovascular disease (CVD) risk factors. Unfortunately, for many Americans it is difficult to sustain a HEP long term which may result in alternating HEP periods. The short term impact of this type of dietary rollercoaster on CVD risk factors requires investigation. The objective of this study was to assess changes in CVD risk factors when subjects adopt, abandon, and then re‐adopt HEPs using data from two previous randomized crossover controlled feeding studies. We hypothesized that subjects would be less responsive to HEP‐induced improvements in CVD risk factors after abandonment of the DASH or Med diet. Subjects in study (S) 1 (n=15) consumed a DASH diet for two 6‐wk periods and subjects in S 2 (n=38) consumed a Med diet for two 5‐wk periods. The first and second HEP periods of both studies were separated by a washout period (mean=5 wk, median=4 wk). Subjects in both studies consumed the HEP during both periods which differed by the amount of red meat. Clinical measures of CVD risk (fasted and 24‐h ambulatory blood pressures (BPs) and blood lipoprotein concentrations) were assessed at baseline and during the last week (post) of each HEP period. The combined age and BMI of subjects (n=53, 19 M, 34 F) was 50 ± 2 y and 31 ± 1 kg/m2, respectively. A mixed effects ANOVA with doubly repeated measures was performed with a SAS glimmix procedure. The model assessed the main effect of S (1 vs 2), diet (high vs low red meat), time (pre vs post), period order, and interactions with a random subject effect. Data are shown as LS mean ± SEM adjusted for age, sex, and body mass. Post hoc analyses were performed using lsmestimate statements to compare CVD risk factors at each chronological time point (pre period 1, post period 1, pre period 2, post period 2), and the change magnitude using a Bonferroni adjustment. Only a main effect of time was observed. Adopting, abandoning, and re‐adopting HEPs decreased, increased, and then decreased indexes of CVD risk. Examples include total 24‐h systolic BP (−5 ± 2, 7 ± 3, and −7 ± 2 mm Hg, respectively) and total cholesterol (TC) (−18 ± 4, 26 ± 8, and −13 ± 4 mg/dL, respectively). Comparable patterns of change occurred for fasted supine systolic and diastolic BPs and LDL and HDL cholesterols but not TC:HDL. The magnitude of changes in CVD risk factors after adopting, abandoning, and re‐adopting the healthy eating pattern were not different. These results show that the cardiovascular benefits of adopting HEPs occur quickly, but are short‐lived when less HEPs are re‐established. Re‐adopting a HEP after lapsing from previous consumption does not blunt re‐gaining improvements in CVD risk factors. These findings support the importance of consistently consuming a healthy eating pattern for cardiovascular health, in part, because clinical CVD risk factors are sensitive to short‐term eating changes.Support or Funding InformationPork Checkoff (S 1 and 2), Beef Checkoff (S 2), NIH UL1TR001108 (S 1 and 2), USDA 2011‐38420‐20038 (S1), and NIH 5T32DK076540‐08 (S 2)