The Effects of High Sugar Diets on the Growth and Structure of the Rat
C. M. Jackson
(From the Department of Anatomy, University of Minnesota, Minneapolis)
1. Thirty-six rats were reared from time of weaning to nearlyadult stage on balanced diets containing 45 per cent starch(controls), 45 per cent sucrose or 80 per cent sucrose. Therats all remained normal in health, vigor and external appearance.
2. Growth in body weight was normal, with no significant differencesbetween the starch-fed (control) and the sugar-fed groups.
3.Reproduction appeared practically normal in the females,asshown by the time of vaginal opening, the estrus cycles,birthof litters, and lactation performance.
4. At autopsy, no abnormalitieswere found in body length, taillength, or gross appearanceof the various regions, parts, ororgans, excepting the liver.The middle ears and lungs are subjectto infections, which werenot more frequent in the sugar-fedthan in the starch-fed (controls).
5. In weight, most of the various parts and organs appearednormal and nearly equal in the starch-fed (control) and sugarfed groups. Differences (usually of somewhat questionable significance)included, especially in the 80 per cent sugar-fed group, anapparent decrease in average weight of the hypophysis, and anincrease in the intestines, kidneys, submaxillary glands, pancreasand (especially) the liver.
6. Incidentally it was found thatin general the Long-Evansstrain of pied (hybrid) rats, whichwas used in the presentexperiments, differs markedly from theWistar norm in weightof the body and of certain organs.
7.A careful histological study of the various organs in bothstarchfedand sugar-fed rats revealed no significant abnormalityof structure,excepting in the liver.
8. The liver in the 80 per cent sugar-fedgroup was enlarged,with (usually) more yellowish color anddistinct surface lobulation.In histological sections most ofthis group showed marked fattydeposits in the glandular epitheliumat the periphery of thelobules. In the other groups slighteramounts of fatty changefrequently appeared, but more irregularin location, with nodifference between the starch-fed and sugar-fedgroups.
9. Caution should be exercised in applying the resultsof thepresent experiment to human diets.