Effect of Incorporating 1 Avocado Per Day Versus Habitual Diet on Visceral Adiposity: A Randomized Trial

Abstract

Background Excess visceral adiposity is associated with increased risk of cardiometabolic disorders. Short-term well-controlled clinical trials suggest that regular avocado consumption favorably affects body weight, visceral adiposity, and satiety. Methods and Results The HAT Trial (Habitual Diet and Avocado Trial) was a multicenter, randomized, controlled parallel-arm trial designed to test whether consuming 1 large avocado per day for 6 months in a diverse group of free-living individuals (N=1008) with an elevated waist circumference compared with a habitual diet would decrease visceral adiposity as measured by magnetic resonance imaging. Secondary and additional end points related to risk factors associated with cardiometabolic disorders were assessed. The primary outcome, change in visceral adipose tissue volume during the intervention period, was not significantly different between the Avocado Supplemented and Habitual Diet Groups (estimated mean difference (0.017 L [-0.024 L, 0.058 L], P=0.405). No significant group differences were observed for the secondary outcomes of hepatic fat fraction, hsCRP (high-sensitivity C-reactive protein), and components of the metabolic syndrome. Of the additional outcome measures, modest but nominally significant reductions in total and low-density lipoprotein cholesterol were observed in the Avocado Supplemented compared with the Habitual Diet Group. Changes in the other additional and post hoc measures (body weight, body mass index, insulin, very low-density lipoprotein concentrations, and total cholesterol:high-density lipoprotein cholesterol ratio) were similar between the 2 groups. Conclusions Addition of 1 avocado per day to the habitual diet for 6 months in free-living individuals with elevated waist circumference did not reduce visceral adipose tissue volume and had minimal effect on risk factors associated with cardiometabolic disorders. Registration URL: https://clinicaltrials.gov; Unique identifier: NCT03528031.

Keywords: avocado; habitual diet; randomized clinical trial; risk factors for cardiometabolic disorders; visceral fat.

Figure 1. Consolidated Standards of Reporting Trials (CONSORT) diagram.

MRI indicates magnetic resonance imaging.

Figure 2. Visceral adipose tissue by subgroup.

For each subgroup, the estimated difference of the 6‐month effects on VAT between the Avocado Supplemented Diet group and the Habitual Diet group is shown as a solid square with a horizontal line showing its 95% CI. At the right, the estimated 6‐month effect on VAT from the mixed effects model is shown for each group along with a P value for the interaction terms, except for Overall, which is the P value for the difference. HEI indicates Healthy Eating Index (range from 0 to 100); Kcal, kilocalories; NonH White, Non‐Hispanic White; and VAT, visceral adipose tissue volume (in liters).