Dissertations and Theses @ UNI


Open Access Thesis


Caffeine--Physiological effect; Women college students--Health and hygiene; Academic theses;


It is commonly believed that caffeine negatively effects hydration status by acting as a diuretic agent. However, previously reported findings on the effects of caffeine on hydration status are controversial. These studies predominantly used healthy college-aged males. Researchers have suggested that females may respond differently to caffeine than males. Some of these differences may be attributed to menstrual cycle and oral contraceptive steroid (OCS) use. The purpose of this study was to investigate whether a 365 mg dose of caffeine would alter urine output (volume) and hydration status (urine specific gravity) in college-aged females while controlling for the menstrual cycle and OCS use. Nineteen females (age= 22±2 years, height= 165.4±8.7 cm, weight= 62.3 ±9.8 kg, body fat= 24.3±5.5%) were separated into three groups based on their OCS use. The two trials (single blind random crossover) included 1) 365 mg dose of caffeine (three 12 oz cans of Mountain Dew with 200 mg of No Doz added) 2) 0 mg of caffeine (three 12 oz cans of Caffeine Free Mountain Dew). Urine volume and urine specific gravity (USG) were determined before and after the eight hour urine collection time. No significant differences were found among variables (p>0.05). In summary there is little evidence to suggest that caffeine will negatively affect urine output or hydration status.

Year of Submission


Degree Name

Master of Arts


School of Health, Physical Education, and Leisure Services

First Advisor

Forrest Dolgener

Second Advisor

Robin Lund

Third Advisor

Kevin Finn


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Date Original


Object Description

1 PDF file (68 leaves)



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