Author
HRUBY, ADELA - Jean Mayer Human Nutrition Research Center On Aging At Tufts University | |
JACQUES, PAUL - Jean Mayer Human Nutrition Research Center On Aging At Tufts University |
Submitted to: Current Developments in Nutrition
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 3/21/2019 Publication Date: 3/28/2019 Citation: Hruby, A., Jacques, P.F. 2019. Dietary protein and changes in biomarkers of inflammation and oxidative stress in the Framingham Heart Study Offspring cohort. Current Developments in Nutrition. https://doi.org/10.1093/cdn/nzz019. DOI: https://doi.org/10.1093/cdn/nzz019 Interpretive Summary: Chronic inflammation is thought to be a major characteristic of aging and chronic disease, such as heart disease. Inflammation may increase the need for certain nutrients, including protein. To combat these inflammatory processes, some people may need more of a given nutrient, such as protein. In this paper, researchers evaluated relationships between dietary protein and markers of inflammation over the long-term (about 7 years) in group of community-dwelling individuals, members of a study called the Framingham Heart Study Offspring Cohort. The researchers measured 9 common markers of inflammation found in the blood and created an inflammation score from these markers, designed to reflect the overall burden of inflammation in any single individual: the higher the score, the higher the overall level of inflammation. They found that lower total protein intake was associated with potentially harmful changes in overall inflammation, whereas higher protein intake appeared favorably related to changes in inflammation. In addition, protein from plants, appeared to be particularly favorable, while protein from animals appeared more neutral, for inflammation. The researchers concluded that dietary protein, particularly from plant sources, may be associated with beneficial changes in the inflammatory burden in aging populations. Technical Abstract: Background: Chronic inflammation is thought to be a major characteristic of aging, which may increase need for substrates, specifically protein, to support anti-inflammatory processes. Objective: To assess associations between dietary protein intake and changes in markers of inflammation over the long-term in a community-dwelling population. Design: In 2,106 participants of the Framingham Heart Study Offspring cohort who attended exams 7 (1998-2001; mean [SD] age 60.0 [8.8] y, 56% female) and 8 (2005-2008), total, animal, and plant protein intakes were assessed by food frequency questionnaire at each exam, energy-adjusted, and averaged. We defined an inflammation score as the sum of rank-normalized values of 9 circulating markers (C-reactive protein [CRP], osteoprotegerin, P-selectin, tumor necrosis factor receptor-II [TNFRII], soluble intercellular adhesion molecule-1 [ICAM-1], interleukin 6 [IL-6], monocyte chemoattractant protein-1 [MCP-1], lipoprotein phospholipase A2 [LPL-A2] mass and activity), and urinary isoprostanes. Adjusted least-square means of changes in the scores and log individual markers in quartile categories of intake were estimated using linear regression models, across mean (SD) 6.6 (0.7) y of follow-up. Results: Protein intake was inversely associated with changes in the inflammation score (mean [SE] in Q1 v. Q4: 0.77[0.17] v. 0.31[0.19], P trend=0.02), indicating overall inflammation increased less in those with the highest protein intake than in those with the lowest. Favorable associations were observed for plant protein (Q1 v.Q4: 0.89[0.25] v. 0.14[0.25], P trend=0.001), but only trended toward significance for animal protein (Q1 v. Q4: 0.70[0.26] v. 0.31[0.26], P trend=0.05). Total protein and plant protein intakes were also inversely associated with changes in MCP-1 (total: Q1 v.Q4: 0.19 [0.01] v. 0.15 [0.01] log-pg/mL, P trend=0.03; plant: Q1 v. Q4: 0.21 [0.01] v. 0.16 [0.01] log-pg/mL, P trend=0.003). Conclusions: Dietary protein, particularly from plant sources, may be associated with beneficial changes in the inflammatory burden in aging populations. |