CleanLineChameleons
Avid Member
Hello everyone!
My name is Stacey and I am a Human Nutritionist. I have a Bachelor's Degree in Human Nutrition with a minor in Chemistry and am currently working to obtain my Master's of Science, as well as my RD status. I have special interests in chemical metabolism, as well as Maternal and Child Nutrition.
It is always exciting to come across people who care so much for their pets and their health. However, I think that, after reading some of the threads concerning vitamins and minerals and their usage in the chameleon nutritive cycle, there are some very serious misconceptions floating around. The following is my personal position on vitamin A metabolism and supplementation.
First and foremost, I think it is important that everyone understand what Vitamin A is and what it does. Vitamin A (some refer to it as pre-formed vitamin A) is a chemical compound known as retinol, which is converted in the body to retinal and used via various transport systems, most specifically the enterohepatic circulation involving RBP (retinol-binding protein). Retinol is important for cell development, reproductive processes, bone metabolism, hematopoesis, iron distribution, and immune function (both humoral and cell-mediated). Certain forms are considered to be useful as free-radical "quenchers," or anti-oxidants. Vitamin A interacts with vitamins E and K, protein, zinc, and iron (sometimes in both beneficial and detrimental ways depending on the balance of each).
In humans, fish, and chicken, vitamin A is absorbed by the small intestine and metabolized in the liver (in poultry, the liver both absorbs and metabolizes the vitamin). There even exists a mechanism by which the body recycles vitamin A via enterohepatic circulation as needed, to help conserve the supply of the fat-soluble vitamin.
VAD (Vitamin A Deficiency) is a declining problem in developing countries, and nearly non-existent in developed ones. Advanced VAD causes permanent blindness, while milder versions can appear as temporary night-blindness. However, before eye problems emerge, consistent VAD tends to result in anorexia, retarded growth, and recurring infections. To combat this problem in humans, many developing countries distribute red or blue capsules containing 200,000 IU and 100,000 IU respectively to children and adults one to two times yearly. In fact, "because vitamin A can be stored in the body for some time, [human] supplementation twice per year is a feasible way to prevent deficiency," (Bryant, DeWalt, Courtney, & Schwartz, 2003). When preventing deficiency, as above discussed, for humans the dosage twice per year can be as little as 10,000IU (the amount found in a typical vitamin A capsule purchased from stores such as GNC). In fact, 10,000 IU is also the upper tolerable limit (UL), when considering daily recommended allowances. The RDA for humans, established in 2001, approximated that 625ug (micrograms) of retinol (or pre-formed vitamin A) per day is enough for an adult male, and much of the literature suggests this may be much more than enough to prevent deficiency and promote good health.
It is important to understand that these are the amounts recommended for an average 180lb adult male human. One drop from a 10,000IU capsule is likely enough as a yearly dosage (considering the proportional difference) for an adult male chameleon, and twice yearly to promote cell development in younger chameleons. Consider the rarity of small lizard and blood-sucking insect consumption by chameleons in the wild and their size in relation to the amount of meat that humans consume. The limited frequency of the consumption of these sources of vitamin A is yet another indicator of the low levels of vitamin A required by chameleons. The research reveals that it takes as little as 3 to 4 times the RDA for humans to cause toxicity, or hypervitaminosis A. That means that if you have provided your chameleon with one full capsule (10,000IU in the span of a month or even a year) there is a great chance that you have provided more than the UL (upper tolerable limit) and may even be crossing into toxic amounts. In fact, for a 100g chameleon, approximately 12.22IU/day is pushing the upper tolerable limits. This equates to about one third of a typical human-use vitamin A capsule (10,000IU) per YEAR. The signs of toxicity include anorexia, edema, excessive shedding (or dry skin), conjunctivitis, ataxia, hyperplasia, hypertrophy, fibrogenesis, sclerosis of the veins, portal hypertension, and hepatocellular damage. These signs are found not only in mammals, but also in fish and poultry (a great indicator that these would be the signs for reptiles as well). These signs are (as is the case with most illnesses) common and can appear to be the same signs as hypovitaminosis A or VAD, blurring the ability to diagnose the chameleon without serum or tissue evaluation.
I would caution all chameleon caretakers and breeders of the supplementation of any vitamin or mineral. In most cases, wild animals consume what is needed by their bodies. Much of the research surrounding additional supplementation occurred prior to the discovery of proper gut-loading methods. Consistently successful breeding of chameleons has shown that calcium and vitamin D supplementation are beneficial to the health and development of the chameleon. That is not the case for vitamin A. In fact, consistently successful breeding and rearing of chameleons has shown that a lack of vitamin A supplementation still results in very healthy chameleons (MM).
It is my well-trained, but unprofessional opinion that, regardless of the current lack of research, chameleons can, in fact, convert beta-carotene to retinol and then retinal for use in the body, and if they cannot do so, most arthropods (insects) can. Feeding carrots to crickets has a very good chance of producing appropriate amounts of vitamin A (in either form) for chameleon absorption and usage. This also promotes receiving the vitamin from a food source and therefore in conjunction with other vitamins, minerals, and phytochemicals that work synergistically in the body to promote optimal health and an appropriate balance of the above chemicals.
Gravid females are more likely to experience temporary VAD (in which levels return to normal after birth or laying), however I would still caution additional supplementation, because excessive amounts are teratogenic. Recent research (from 2003) suggests providing an extra 1-2 IU/wk for females in breeding season. I would say that this is probably a bit high considering the amount received from properly gut-loaded crickets that could compound the amount absorbed by the chameleon. To play it safe, yet provide additional vitamin supplementation for the gravid female, consider providing 1-2IU of pre-formed vitamin A per breeding season.
There is a fine line with vitamin A between deficiency, appropriate status, and toxicity. Because of the lack of formal research on chameleons, the severity of hypervitaminosis, and the perpetually successful production of chameleons without supplementation, I conclude that additional supplementation of the vitamin is unnecessary in most cases, and could potentially be beneficial in the form of one drop (or about 15% of a human-use capsule), two times per year for growing chameleons, and one drop (about 15% of a human-use capsule) one time per year for full grown chameleons. As is the case with most recommendations, more research is needed. However, the research and information that exists for both humans and chameleons supports that the above recommendation is conservatively appropriate.
Keep in mind, also as has been said in previous threads, that vitamins and minerals are NOT treatments. If something appears to be wrong with your chameleon, using a vitamin as a medication can not only be a misdiagnosis (causing your chameleon to have proper medication withheld), but detrimental (as is the case with overdoses). For example, if the chameleon has what appears to be conjunctivitis (swelling with the appearance of puss around and in the eye), this could be the result of a much more serious infection (puss is the collection of dead white blood cells, often killed by a virus, bacteria, or protozoa that exists at the site of infection) or it could be a sign of hypervitaminosis A. Treating the problem with vitamin A could either do nothing (in the case of microbial infection) and allow the untreated infection to worsen, or it could cause permanent keratomalacia, scarring, and permanent blindness (as would be the case if the conjunctivitis has been caused by a vitamin A overdose -- the latter of the above cases). If something appears to be wrong with your chameleon, please contact a veterinarian for the appropriate evaluation and treatment.
There is no vitamin or mineral that has greater importance than any others. Humans and animals alike require varying amounts of each of them. They require various amounts of kilocalories and other chemicals as well, all of which work together to improve the health and well-being of your pet. Too much or too little of any one chemical throws off that essential balance and can cause serious detrimental effects.
If anyone has any questions or would like further clarity on this topic or others involving the nutrition of your pets, please feel free to contact me via this thread, (or a PM if you so desire).
Thank you for your time and for your open-mindedness on the topic. Always, with our beloved animals and children, it is best to err on the side of safety and provide your pets and children with time-tested care.
Sincerely,
Stacey, a Clean Line Chameleon associate
My name is Stacey and I am a Human Nutritionist. I have a Bachelor's Degree in Human Nutrition with a minor in Chemistry and am currently working to obtain my Master's of Science, as well as my RD status. I have special interests in chemical metabolism, as well as Maternal and Child Nutrition.
It is always exciting to come across people who care so much for their pets and their health. However, I think that, after reading some of the threads concerning vitamins and minerals and their usage in the chameleon nutritive cycle, there are some very serious misconceptions floating around. The following is my personal position on vitamin A metabolism and supplementation.
First and foremost, I think it is important that everyone understand what Vitamin A is and what it does. Vitamin A (some refer to it as pre-formed vitamin A) is a chemical compound known as retinol, which is converted in the body to retinal and used via various transport systems, most specifically the enterohepatic circulation involving RBP (retinol-binding protein). Retinol is important for cell development, reproductive processes, bone metabolism, hematopoesis, iron distribution, and immune function (both humoral and cell-mediated). Certain forms are considered to be useful as free-radical "quenchers," or anti-oxidants. Vitamin A interacts with vitamins E and K, protein, zinc, and iron (sometimes in both beneficial and detrimental ways depending on the balance of each).
In humans, fish, and chicken, vitamin A is absorbed by the small intestine and metabolized in the liver (in poultry, the liver both absorbs and metabolizes the vitamin). There even exists a mechanism by which the body recycles vitamin A via enterohepatic circulation as needed, to help conserve the supply of the fat-soluble vitamin.
VAD (Vitamin A Deficiency) is a declining problem in developing countries, and nearly non-existent in developed ones. Advanced VAD causes permanent blindness, while milder versions can appear as temporary night-blindness. However, before eye problems emerge, consistent VAD tends to result in anorexia, retarded growth, and recurring infections. To combat this problem in humans, many developing countries distribute red or blue capsules containing 200,000 IU and 100,000 IU respectively to children and adults one to two times yearly. In fact, "because vitamin A can be stored in the body for some time, [human] supplementation twice per year is a feasible way to prevent deficiency," (Bryant, DeWalt, Courtney, & Schwartz, 2003). When preventing deficiency, as above discussed, for humans the dosage twice per year can be as little as 10,000IU (the amount found in a typical vitamin A capsule purchased from stores such as GNC). In fact, 10,000 IU is also the upper tolerable limit (UL), when considering daily recommended allowances. The RDA for humans, established in 2001, approximated that 625ug (micrograms) of retinol (or pre-formed vitamin A) per day is enough for an adult male, and much of the literature suggests this may be much more than enough to prevent deficiency and promote good health.
It is important to understand that these are the amounts recommended for an average 180lb adult male human. One drop from a 10,000IU capsule is likely enough as a yearly dosage (considering the proportional difference) for an adult male chameleon, and twice yearly to promote cell development in younger chameleons. Consider the rarity of small lizard and blood-sucking insect consumption by chameleons in the wild and their size in relation to the amount of meat that humans consume. The limited frequency of the consumption of these sources of vitamin A is yet another indicator of the low levels of vitamin A required by chameleons. The research reveals that it takes as little as 3 to 4 times the RDA for humans to cause toxicity, or hypervitaminosis A. That means that if you have provided your chameleon with one full capsule (10,000IU in the span of a month or even a year) there is a great chance that you have provided more than the UL (upper tolerable limit) and may even be crossing into toxic amounts. In fact, for a 100g chameleon, approximately 12.22IU/day is pushing the upper tolerable limits. This equates to about one third of a typical human-use vitamin A capsule (10,000IU) per YEAR. The signs of toxicity include anorexia, edema, excessive shedding (or dry skin), conjunctivitis, ataxia, hyperplasia, hypertrophy, fibrogenesis, sclerosis of the veins, portal hypertension, and hepatocellular damage. These signs are found not only in mammals, but also in fish and poultry (a great indicator that these would be the signs for reptiles as well). These signs are (as is the case with most illnesses) common and can appear to be the same signs as hypovitaminosis A or VAD, blurring the ability to diagnose the chameleon without serum or tissue evaluation.
I would caution all chameleon caretakers and breeders of the supplementation of any vitamin or mineral. In most cases, wild animals consume what is needed by their bodies. Much of the research surrounding additional supplementation occurred prior to the discovery of proper gut-loading methods. Consistently successful breeding of chameleons has shown that calcium and vitamin D supplementation are beneficial to the health and development of the chameleon. That is not the case for vitamin A. In fact, consistently successful breeding and rearing of chameleons has shown that a lack of vitamin A supplementation still results in very healthy chameleons (MM).
It is my well-trained, but unprofessional opinion that, regardless of the current lack of research, chameleons can, in fact, convert beta-carotene to retinol and then retinal for use in the body, and if they cannot do so, most arthropods (insects) can. Feeding carrots to crickets has a very good chance of producing appropriate amounts of vitamin A (in either form) for chameleon absorption and usage. This also promotes receiving the vitamin from a food source and therefore in conjunction with other vitamins, minerals, and phytochemicals that work synergistically in the body to promote optimal health and an appropriate balance of the above chemicals.
Gravid females are more likely to experience temporary VAD (in which levels return to normal after birth or laying), however I would still caution additional supplementation, because excessive amounts are teratogenic. Recent research (from 2003) suggests providing an extra 1-2 IU/wk for females in breeding season. I would say that this is probably a bit high considering the amount received from properly gut-loaded crickets that could compound the amount absorbed by the chameleon. To play it safe, yet provide additional vitamin supplementation for the gravid female, consider providing 1-2IU of pre-formed vitamin A per breeding season.
There is a fine line with vitamin A between deficiency, appropriate status, and toxicity. Because of the lack of formal research on chameleons, the severity of hypervitaminosis, and the perpetually successful production of chameleons without supplementation, I conclude that additional supplementation of the vitamin is unnecessary in most cases, and could potentially be beneficial in the form of one drop (or about 15% of a human-use capsule), two times per year for growing chameleons, and one drop (about 15% of a human-use capsule) one time per year for full grown chameleons. As is the case with most recommendations, more research is needed. However, the research and information that exists for both humans and chameleons supports that the above recommendation is conservatively appropriate.
Keep in mind, also as has been said in previous threads, that vitamins and minerals are NOT treatments. If something appears to be wrong with your chameleon, using a vitamin as a medication can not only be a misdiagnosis (causing your chameleon to have proper medication withheld), but detrimental (as is the case with overdoses). For example, if the chameleon has what appears to be conjunctivitis (swelling with the appearance of puss around and in the eye), this could be the result of a much more serious infection (puss is the collection of dead white blood cells, often killed by a virus, bacteria, or protozoa that exists at the site of infection) or it could be a sign of hypervitaminosis A. Treating the problem with vitamin A could either do nothing (in the case of microbial infection) and allow the untreated infection to worsen, or it could cause permanent keratomalacia, scarring, and permanent blindness (as would be the case if the conjunctivitis has been caused by a vitamin A overdose -- the latter of the above cases). If something appears to be wrong with your chameleon, please contact a veterinarian for the appropriate evaluation and treatment.
There is no vitamin or mineral that has greater importance than any others. Humans and animals alike require varying amounts of each of them. They require various amounts of kilocalories and other chemicals as well, all of which work together to improve the health and well-being of your pet. Too much or too little of any one chemical throws off that essential balance and can cause serious detrimental effects.
If anyone has any questions or would like further clarity on this topic or others involving the nutrition of your pets, please feel free to contact me via this thread, (or a PM if you so desire).
Thank you for your time and for your open-mindedness on the topic. Always, with our beloved animals and children, it is best to err on the side of safety and provide your pets and children with time-tested care.
Sincerely,
Stacey, a Clean Line Chameleon associate
