The Dietary Variety Score: assessing diet quality in healthy young and older adults

To develop a new dietary variety score (DVS) and link it to other measures of diet quality, including a modified diet quality index (DQI).

The subjects were 24 healthy young (ages 20 to 30 years) and 24 healthy older (ages 60 to 75 years) adults, including 24 men and 24 women. Their dietary intake assessments were based on one 24-hour food recall interview and 14 consecutive days of food records.

Energy and nutrient intakes were estimated using Nutritionist IV software. DVS was based on the cumulative number of different foods consumed over the 15-day period. DQI was a 5-point scale based on conformity with the key US dietary recommendations. Full score was awarded for diets deriving 30% or less of energy from fat, 10% or less of energy from saturated fat, more than 50% of energy from carbohydrate, and containing less than 300 mg cholesterol and 2,400 mg sodium per day. Analytic measures included analyses of variance, correlation analyses, and chi 2 tests.

Older subjects consumed more varied diets than did young subjects. Higher DVS values were linked positively to vitamin C intakes and negatively to the consumption of salt, sugar, and saturated fat. However, a high DVS was not linked to a high score on the DQI in this subject sample.

Few studies have addressed the issue of how many different foods constitute a varied diet. The present classification scheme offers a new way of assessing dietary variety at the individual or group level. Measures of dietary variety may represent an additional facet of diet quality and their relationship to selected health outcomes should be examined further.