Individuals with spinal cord injury (SCI) are living to ages when metabolic disorders are highly prevalent. The combination of impaired glucose tolerance and insulin resistance can disrupt lipid metabolism and increase the risk of cardiovascular disease and diabetes, and contribute to an accelerated aging process in the SCI population. Feasible interventions to improve metabolic function in the chronic SCI are in great demand. Compared to pharmacologic therapies, dietary modification is a more cost-effective treatment option for reducing the risk of metabolic dysfunction that, surprisingly, has not been rigorously investigated in people with SCI. Therefore, in the present study the investigators will investigate the efficacy of an 8-week, eucaloric (a meal plan designed specifically to provide the exact amount of calories needed to maintain a given body weight) LC-HP dietary intervention for improving metabolic function, body composition, gut bacteria composition and quality of life in individuals with SCI and impaired glucose tolerance or type 2 diabetes. The investigators also aim to determine the association between changes in the composition of gut bacteria and improvements in metabolic function and the association between improvements in metabolic function and improvements in quality of life.