Snacking Consumption among Adults in the United States: A Scoping Review

**Background:** Snacks are a staple of the American diet, contributing approximately 20% of total energy intake among adults, with over 90% of U.S. adults reporting one or more snacks per day. Despite the prevalence of snacking, few reviews have focused specifically on snacking behaviors among U.S. adults. This scoping review aimed to characterize snacks and snacking occasions among U.S. adults to inform healthy eating practices. The review addressed three questions: what is being consumed as snacks, what motivates snack food choice, and when does snacking occur?

**Methods:** The protocol followed the PRISMA-Extension for Scoping Reviews and was registered in the Open Science Framework. Three databases (PubMed, Ovid, Scopus) were searched for articles published between January 2010 and May 2022. Inclusion criteria were peer-reviewed studies focused on adults (≥18 years) living in the U.S., written in English or Spanish. Quantitative, qualitative, and mixed-method studies were included. A two-stage screening process (title and abstract) identified 31 of 4795 publications meeting inclusion criteria. Data extraction included author, year, location, objectives, population, sample size, methods, and major findings.

**Key Results:** The 31 studies varied in design: 15 cross-sectional, 7 randomized controlled trials, 2 prospective, 1 factorial cross, 1 longitudinal pilot, and 1 case study. Sample sizes ranged from 4 to 19,427 participants. Studies were conducted across the U.S., with 12 in a single city, 4 in a single state, 4 multistate, 1 regional, and 6 nationwide. Three main themes emerged: (1) cues and motivations for snacking (e.g., stress, taste, convenience); (2) snacking vs. any eating occasion; and (3) diet composition and health.

Snacking frequency averaged 1.5–3 times per day. One study reported healthy snacks consumed 0.6 times/day and unhealthy snacks 0.8 times/day. Snacking occurred throughout the day, with morning snacks (8:00–11:30 a.m.) least common and afternoon snacks (1:00–5:30 p.m.) most common. Late-night snacking (8:00 p.m.–midnight) was associated with less healthy choices. The average daily eating interval was 11.6 hours. Snacks contributed about 20% of daily energy intake. Protein intake from snacks ranged from 4.9 to 16.5 g/day. Among older adults, higher snacking frequency was associated with increased intake of vitamins A, C, E, B-6, beta carotene, magnesium, copper, and potassium. Morning snacking was linked to higher fruit and vegetable consumption, while evening snacking was associated with higher BMI and obesogenic dietary patterns. Taste was the most fundamental driver of snack choice, with convenience, hunger, and health also important. Three snack classifications were identified: by time of day, by nutrient quality (high-quality, low-quality, mixed-quality), and by healthfulness (healthy vs. unhealthy based on fat, cholesterol, sodium).

**Clinical Implications:** Snacking can be a vehicle for improving diet quality if healthy options (fruits, vegetables, low-fat dairy) are chosen. Nutrition education should emphasize strategic snack selection, particularly during afternoon and evening peaks when unhealthy choices are common. The lack of a standardized snack definition limits comparability across studies and hinders policy development. A universal definition would strengthen research and inform dietary guidelines. Clinicians can use these findings to counsel patients on mindful snacking, timing, and quality to support weight management and reduce chronic disease risk.