Association of fiber intake and fruit/vegetable consumption with weight gain in a Mediterranean population

Abstract

Objective

We assessed the association between fiber intake and fruit/vegetable consumption with the likelihood of weight gain in the previous 5 y in a Mediterranean population.

Methods

We conducted a cross-sectional analysis of participants (5094 men and 6613 women) in a multipurpose prospective cohort (Seguimiento Universidad de Navarra Study). Diet was measured by using a semiquantitative food-frequency questionnaire that was previously validated in Spain. We calculated the odds ratios of weight gain in the previous 5 y according to quintiles of energy-adjusted fiber intake and quintiles of energy-adjusted of fruit/vegetable consumption. We also considered the joint exposure to fiber intake and fruit/vegetable consumption.

Results

Multivariate-adjusted odds ratios for weight gain across quintiles 1 to 5 of fiber intake were 1.00 (reference), 0.86, 0.86, 0.70, and 0.52 (P for trend < 0.001) among men and 1.00 (reference), 0.99, 1.08, 1.05, and 0.72 (P for trend = 0.005) among women. We also observed a significant inverse association between total fruit/vegetable consumption and weight gain, but only among men (adjusted odds ratios, 0.78, 0.89, 0.70, and 0.54 for quintiles 2 to 5, P for trend < 0.001). The inverse association between fruit/vegetable consumption and weight gain in the previous 5 y was more evident among those with a high intake of total fiber, and the benefit of total fiber was more evident among those with a high consumption of fruits and vegetables.

Conclusions

This study provides additional support to the inverse association between fiber or fruit/vegetable consumption and weight gain, thus emphasizing the importance of replacing some dietary compounds by such foods and fiber-rich products, which may help to avoid weight gain.

Introduction

Obesity is a common and growing public health problem in industrialized and developing countries [1], where increasing rates are accompanied by a sharp increase in the incidence of type 2 diabetes mellitus, cardiovascular diseases, and some types of cancer such as colorectal cancer in men, cancer of the endometrium, and breast cancer in postmenopausal women [1]. The current prevalence rates show that more than 60% of Americans are overweight or obese [2]. Among European countries, increasing rates of obesity have been also reported [3], [4].

The development of obesity is the consequence of a long-term and sustained energy imbalance when energy intake exceeds energy expenditure (determined by basal metabolic rate, thermogenic effect of foods, and cost of physical activity) [5]. One cause of obesity is genetic background or susceptibility. Nevertheless, lifestyle factors such as physical inactivity and inappropriate dietary habits may be more important to the alarming increase in its prevalence [6].

In recent decades, the prescription of hypocaloric diets has been promoted with the aim of creating a negative energy balance. However, their effects on weight control over time are not satisfactory, so many researchers try to ascertain the specific influence of different macronutrients and micronutrients and other non-nutritional elements contained in food items with the goal of devising reasonable strategies to induce weight loss successfully and prevent further weight gain [7], [8], [9], [10].

A high fiber intake has been associated with weight loss in some studies [11], [12], [13]. Although the overall data suggest a potential preventive role of fiber-rich diets, components other than fiber but included in the same foods (fruits and vegetables) such as antioxidants [14], [15] may exert the same effect on weight regulation. However, evidence from epidemiologic studies is limited only to the fiber effect. Thus, there are few studies that have assessed the joint effect of fiber intake and fruit/vegetable consumption [16]. Further, most previous studies on this topic have focused mainly on women [11], [16], [17]. This analysis studied the association between fiber intake, fruit/vegetable consumption, and the likelihood of weight gain in Spain, a country with a traditional Mediterranean dietary pattern.