Effects of Reduced-fat Diets Consumed Ad Libitum on Intake of Nutrients, Particularly Antioxidant Vitamins
Section snippets
Subjects
Participants were selected from the Workforce Diabetes Survey (19) in which glucose tolerance tests were performed in 5,677 workers older than 40 years from 41 worksites around Auckland, New Zealand, between 1988 and 1990. One hundred sixty-two (2.8%) of those surveyed were classified as having impaired glucose tolerance (2-hour blood glucose concentration 7.8 to 11.0 mmol/L)1
Subjects
Sixty-three percent of participants who started the trial completed it with full dietary data available for analysis (N=110; see Table 1). The mean age for this group was 53 years; the range was narrow because the minimum age for inclusion in the original workforce diabetes survey was 40 years. No differences were noted in mean initial weight or body mass index (calculated as kg/m2) between the 2 groups (reduced-fat intake and control). All participants originally had a 2-hour blood glucose
Discussion
We examined the effects of a 12-month, reduced-fat diet consumed ad libitum on dietary intake of macronutrients and micronutrients and on serum levels of antioxidants. Total fat and saturated fat intake decreased significantly, as did their contribution to total energy in the reduced-fat group. Absolute intake of carbohydrate did not change, which indicates no compensatory response for the decrease in energy from fat. Intake of micronutrients was not compromised by the reduction in fat intake
Applications/Conclusions
■ A dietary approach to weight loss that focuses on the reduction of total fat within an otherwise ad libitum diet achieves recommended intakes of macronutrients and dietary cholesterol. To increase intake of dietary fiber, people require more specific instructions such as choosing fiber-rich breads and cereals and increasing vegetable consumption.
■ Similarly, people at high risk of cardiovascular disease may require specific advice on increasing vegetable oil consumption. A deduction in
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