High dietary protein intake is associated with an increased body weight and total death risk

Clin Nutr. 2016 Apr;35(2):496-506. doi: 10.1016/j.clnu.2015.03.016. Epub 2015 Apr 7.

Abstract

Background & aims: High dietary protein diets are widely used to manage overweight and obesity. However, there is a lack of consensus about their long-term efficacy and safety. Therefore, the aim of this study was to assess the effect of long-term high-protein consumption on body weight changes and death outcomes in subjects at high cardiovascular risk.

Methods: A secondary analysis of the PREDIMED trial was conducted. Dietary protein was assessed using a food-frequency questionnaire during the follow-up. Cox proportional hazard models were used to estimate the multivariate-adjusted hazard ratio (HR) and 95% confidence intervals (95%CI) for protein intake in relation to the risk of body weight and waist circumference changes, cardiovascular disease, cardiovascular death, cancer death and total death.

Results: Higher total protein intake, expressed as percentage of energy, was significantly associated with a greater risk of weight gain when protein replaced carbohydrates (HR: 1.90; 95%CI: 1.05, 3.46) but not when replaced fat (HR: 1.69; 95%CI: 0.94, 3.03). However, no association was found between protein intake and waist circumference. Contrary, higher total protein intake was associated with a greater risk of all-cause death in both carbohydrate and fat substitution models (HR: 1.59; 95%CI: 1.08, 2.35; and HR: 1.66; 95%CI: 1.13, 2.43, respectively). A higher consumption of animal protein was associated with an increased risk of fatal and non-fatal outcomes when protein substituted carbohydrates or fat.

Conclusions: Higher dietary protein intake is associated with long-term increased risk of body weight gain and overall death in a Mediterranean population at high cardiovascular risk.

Keywords: Body weight; Cardiovascular; Death; Protein; Risk.

Publication types

  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Body Mass Index
  • Cardiovascular Diseases / epidemiology
  • Cholesterol / blood
  • Dietary Carbohydrates / administration & dosage
  • Dietary Fats / administration & dosage
  • Dietary Proteins / administration & dosage*
  • Dietary Proteins / adverse effects*
  • Energy Intake
  • Female
  • Humans
  • Male
  • Middle Aged
  • Mortality*
  • Nutrition Assessment
  • Obesity / complications
  • Obesity / diet therapy
  • Overweight / complications
  • Overweight / diet therapy
  • Proportional Hazards Models
  • Prospective Studies
  • Randomized Controlled Trials as Topic
  • Risk Factors
  • Surveys and Questionnaires
  • Triglycerides / blood
  • Waist Circumference
  • Weight Gain*

Substances

  • Dietary Carbohydrates
  • Dietary Fats
  • Dietary Proteins
  • Triglycerides
  • Cholesterol