Special nutritional products, such as this, have specific indications and, just as important, contraindications that call for warnings and disclaimers. Products rich in purines should be avoided because of risks regarding gout. Reptiles and amphibians synthesize vitamin C, hence need no dietary ascorbic acid. These data suggest that snakes which are unstressed need no supplementary ascorbate. The data may not hold true for other species, for rates of ascorbate synthesis between species is less an all or none phenomenon, and more a gradient or continuum.
Some species synthesize ascorbate at greater rates than other species.
Excretion rates for vitamin C increase with stress in endotherms, and a similar mechanism may exist in ectotherms. Fermentation of fiber in the lower bowel produces short-chain fatty acids, such as acetate, butyrate, and propionate, from carbohydrate , especially fiber. Short-chain fatty acids are used as fuel by enterocytes, and are absorbed into the circulation. Fermentation in the lower bowel is part of microbial metabolism and allows the proliferation of microbes. These form part of the feces, and their protein and fat is not available for absorption or use by the host animal.