Date of Graduation


Document Type


Degree Name

Doctor of Philosophy in Food Science (PhD)

Degree Level



Food Science


Jamie I. Baum

Committee Member

Elisabet Børsheim

Second Committee Member

Erin K. Howie Hickey

Third Committee Member

Michelle Gray

Fourth Committee Member

Sami Dridi

Fifth Committee Member

Sun-Ok Lee


Aging, Omega-3 polyunsaturated fatty acids, Protein, Quality of life, Skeletal muscle, Well-being


The current growth of the older population is unprecedented in U.S. history. Chronic disease and functional limitation commonly develop prior to old age, leading to prolonged physical disability and decreased well-being. The development of chronic disease and loss of independence is associated with lean body mass (LBM) loss and fat mass gain beginning in middle age. Therefore, it is important to identify modifiable factors to mitigate deleterious shifts in body composition to promote successful aging (SA). The concept of SA is associated with longevity, the absence of disease and disability, and subjective components of well-being, however, an operational definition has yet to be established. For this thesis, we defined SA as low cardiometabolic risk, preservation of physical function, and a positive state of well-being. Nutrition is a key driver of SA and is a proposed modulator of cardiometabolic risk, physical function, and well-being in adults. Among nutrients, several studies have identified dietary protein and the omega-3 polyunsaturated fatty acids (n-3 PUFAs), eicosapentaenoic acid (EPA; 20:5 n-3) and docosahexaenoic acid (DHA; 22:6 n-3), as key supportive nutrients for SA in older adults. Therefore, the overall objective of this dissertation was to determine the effect of nutrition, specifically dietary protein and n-3 PUFAs on SA outcomes of cardiometabolic risk, physical function, and well-being. The central hypothesis of this dissertation was that increased intake of high-quality dietary protein or n-3 PUFAs would improve SA outcomes of cardiometabolic risk, physical function, and well-being in adults. Therefore, one meta-analysis (study 1) and two clinical trials (studies 2 and 3) were designed to test our hypothesis. The objective of the first study was to systematically evaluate the available evidence of randomized control trials assessing the effect of beef and beef’s nutrients on well-being in healthy, adults ≥ 50 years of age to increase physical function and well-being to promote SA. The objective of the second study was to determine and compare the acute effects of a high-protein breakfast containing either animal protein or plant protein on appetite, food intake, energy expenditure, and substrate oxidation in young versus older men to decrease cardiometabolic risk and promote SA. The objective of the third study was to determine the individual and combined effect of protein and n-3 PUFAs on body composition, cardiometabolic risk, indexes of sleep, and mood states in postmenopausal women to decrease cardiometabolic risk and increase physical function, and well-being to promote SA. Collectively, the results suggest high-quality protein and n-3 PUFAs act as potential regulators of SA outcomes. However, additional research is necessary to determine the effectiveness of protein and n-3 PUFA-based nutrition strategies to promote SA.